anexo vii (del alcancel del servicio)design standart automation systems rev2

7/27/2019 Anexo VII (Del Alcancel Del Servicio)Design Standart Automation Systems Rev2

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DESIGN STANDARD : AUTOMATIONSYSTEMS

DRP-1-431-04-9-ES0002

PS025-MI-TS0002

Automation Systems Design Criteria

La Oroya Smelter Design Standards : Automation Systems

DRP-1-431-04-9-ES0000 PS025-MI-TS0000 Automation Standards Instructions

DRP-1-431-04-9-ES0001 PS025-MI-TS0001 General Systems Automation Philosophy

DRP-1-431-04-9-ES0002 PS025-MI-TS0002 Automation Design Criteria

DRP-1-431-04-9-ES0003 PS025-MI-TS0003 Preferred Instrument Equipment Specification

DRP-1-431-04-9-ES0004 PS025-MI-TS0004 Automation Equipment Room Standards

DRP-1-431-04-9-ES0005 PS025-MI-TS0005 Instrument and Controls Installation Specification

DRP-1-431-04-9-ES0010 PS025-MI-TS0010 Instrument Tag Numbering Guidelines

DRP-1-431-04-9-ES0011 PS025-MI-TS0011 Automation Control System Equipment

DRP-1-431-04-9-ES0013 PS025-MI-TS0013 Automation System Documentation

DRP-1-431-04-9-ES0014 PS025-MI-TS0014 Automation Cable Type List

DRP-1-431-04-9-ES0015 PS025-MI-TS0015 Automation System Process Measurement Units

DRP Design Standard Automation System

Document Prepared By:

Xstrata Technology / MIPAC Pty Ltd

Document Approved By:

Design Consultant Brian Forrester

Doe Run Automation Carlos Vivas L., Cesar Chung Ching, Ricardo Caycho

Doe Run Project Manager Godofredo Oporto B

Revisions:

Rev Date By Description Checked

A 28/07/06 ROC Issued for Internal Use GAW

B 21/08/06 WAC Issued for Internal Review BSF

C 23/08/06 BSF Issued for Doe Run Peru Review CCC for DRP

0 08/09/06 WAC Issued for Design CCC for DRP

1 25/09/06 BSF Revised piping standard

2 16/10/06 CC-CV Issued to be used by DRP RC


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Doe Run PeruAutomation Systems Design Criteria

PS027-MI-TS0002 Rev2.doc 16-October-2006 Page: i

TABLE OF CONTENTS

1. INTRODUCTION 11.1 Purpose and Scope of Document 11.2 References 1

2. DEFINITIONS AND ABBREVIATIONS 13. GENERAL DESIGN CRITERIA 2

3.1 Statutory Requirements 23.2 Codes and Standards 23.3 Safety and Environmental 23.4 Site Conditions 23.5 Hazardous Area Requirements 33.6 Automation System Equipment Selection 3

4. OPERATIONAL DESIGN CRITERIA 34.1 Design Life 34.2 Operational Ratings 34.3 Noise 44.4 RFI Immunity 44.5 Immunity from Magnetic Fields 4

5. GENERAL AUTOMATION DESIGN CRITERIA 55.1 Overview 55.2 Automation Control Systems 55.3 Automation Power Supplies 55.4 Instrument Earth Design 55.5 Electrical Control Design 55.6 Instrument Tag Numbering 65.7 Automation Documentation 65.8 Process Measurement Units 6

6. AUTOMATION CONTROL SYSTEMS 66.1 Scope 66.2 Automation Control Equipment Locations 86.3 Automation Control System Integrity 86.4 Individual Hard-wired Interface Signals 106.5 Multiplexed Interface Signals 116.6 Control Equipment Enclosures 116.7 Equipment Cable Connections 126.8 Spare Capacity 12

7. AUTOMATION SYSTEM CABLING 127.1 Automation Cabling Overview 127.2 Automation Cable Arrangements 127.3 Cable Termination Design 13


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PS027-MI-TS0002 Rev2.doc 16-October-2006 Page: ii

7.4 Spare Cable Capacity 137.5 Cable Installation Design 13

8. INSTRUMENTATION REQUIREMENTS 148.1 General 148.2 Instrument Nameplates 148.3 Instrument Tag Labels 158.4 Calibration Certificates 158.5 Process Connections and Instrument Air Supply Connections 158.6 Electrical Connections 158.7 Equipment Enclosures 158.8 Reverse Polarity 168.9 Instrument Isolation 168.10 Calibrated Range 168.11 Instrument Mounting 168.12 Instrument Air Supply 178.13 Instrument Piping and Tubing 18

9. MEASUREMENT TECHNOLOGIES 199.1 Process Analyzers 199.2 Nucleonic Instruments 219.3 Flow 229.4 Level 259.5 Pressure 279.6 Temperature 309.7 Weight 329.8 Position Switches 329.9 Underspeed Detection 32

10. VALVE REQUIREMENTS 3310.1 Control Valve Selection 3310.2 Control Valves (Including Self-Regulating Valves) 3310.3 On/Off Valves (Actuated Type) 3410.4 Shutdown Valves (actuated type) 3410.5 Valve Materials 3410.6 Design and Manufacturing Requirements 3510.7 Selection of Actuator Type 3510.8 Pneumatic Actuators 3610.9 Actuator Sizing 3610.10 Electro-Pneumatic Positioners 3710.11 Hand Wheels 3710.12 Accessories 3710.13 Solenoid Valves 3710.14 Safety Relieving Devices 38


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PS027-MI-TS0002 Rev2.doc 16-October-2006 Page: iii

11. SAFETY INSTRUMENTED SYSTEM INSTRUMENTS 40APPENDIX A RELEVANT ABBREVIATIONS 41


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PS025-MI-TS0002 Rev2.doc 16-October-2006 Page: 1

1. INTRODUCTION

1.1 Purpose and Scope of Document

The purpose of this document is to provide the automation system design criteria to facilitate thestandardization of measurement and control designs for Doe Run Peru. Automation systemsare defined as the process measurement and control systems that are used to operate theplants.

The objectives are to achieve a consistent approach to design and equipment selection for theautomation systems across all operational areas, and to ensure the safe and reliable operationof all automation equipment for the life of the plant. Ongoing maintenance of the plant will alsobe assisted by this common design approach and by the use of common types of automationequipment.

This design criteria document is applicable to instrumentation in all process areas. It is intendedto be read in conjunction with other engineering discipline project specific technicalspecifications produced by others.

This document addresses the following design aspects:

Uniformity of design and design documentation.

Uniformity of the Plant Wide Control System.

Uniformity of field instrumentation.

Reliable control and instrumentation systems capable of supporting profitable plantoperation.

A level of plant automation consistent with minimum effective design.

Definition of minimum effective design - A design which achieves the goals of safe,profitable, and maintainable plant operation, while economizing on capital expenditure.

1.2 References

This document is part of a package of automation standards that shall be applied on Doe RunPeru. The automation standards set out general requirements only and will be supported asnecessary by more detailed project specifications and standard drawings.

The automation standards are listed in an index document that identifies the standards and theassociated project specifications and standard drawings. The principal automation standardsare also listed on the front cover of this document.

2. DEFINITIONS AND ABBREVIATIONSFor relevant abbreviations, refer to Appendix A.


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3. GENERAL DESIGN CRITERIA

3.1 Statutory Requirements

All statutory requirements for designing, constructing and operating the plant in the La OroyaSmelter shall be complied with. The applicable relevant statutory requirements shall be listed in

project specifications. Where relevant statutory requirements have not been identified inautomation standards and project specifications, it is the designers responsibility to determinethese requirements.

Particular attention is drawn to the requirements of the relevant Mining Regulations, ElectricityActs, Environmental Protection Acts, the Workplace Health and Safety Act, and any relevantlocal authority permits and regulations.

3.2 Codes and Standards

All equipment and installations shall comply with the codes and standards nominated in theautomation standards or project specifications. Where no existing automation standards orproject specifications address the specific requirements, work shall conform to the most current

IEC standard or internationally recognized standard that the supplier would normally complywith.

If a conflict is identified between any of the statutory regulations, standards, referencedocuments, and the requirements on drawings, datasheets and this standard, the informationshall be documented and forwarded to Doe Run Peru in accordance with relevant contractprocedures.

3.3 Safety and Environmental

The relevant workplace health and safety requirements and environmental considerations shallbe identified in project specifications. Where specific requirements have not been identified anddocumented, the Peruvian safety and environmental considerations shall apply, and the plant

designer shall be responsible for determining these requirements.

3.4 Site Conditions

Refer to the Doe Run Peru, La Oroya Site General Information specification for the siteconditions and requirements.

In addition to these requirements, all electrical equipment shall be designed to operatecontinuously at full load for 24 hours per day, 365 days per year. Equipment may be required tobe protected against an environment subject to abrasive and corrosive dusts and liquids andvapors.

The design capacity shall allow for the manufacturers recommended maintenance activities

and minor breakdowns to take place.

It should be noted that the La Oroya site is located at an elevation of 3800m above sea leveland so all electrical equipment should be capable of operating as specified at this elevation.Motors shall be nameplated for the altitude of operation on site. DRP will not accept de-ratingfor electric motors.

The ambient temperature can range from -5C (minimum, winter) to 30C (maximum, summer).Particular attention should be paid to the suitability of equipment to operate over thistemperature range, and in particular to pneumatic equipment that could be affected by thepresence of moisture at low temperatures.


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3.5 Hazardous Area Requirements

All electrical equipment that is to be installed in locations where flammable atmospheres mayexist shall comply with the relevant Peruvian hazardous area requirements.

Design work for hazardous area equipment shall not commence until an approved projectspecification defining the following is available:

Relevant Peruvian legislative requirements and standards

Doe Run preferred explosion protection techniques and design standards

Explosion protection identification and labeling requirements

Documentation and certification requirements.

3.6 Automation System Equipment Selection

3.6.1 Instrumentation and Bulk Equipment

Equipment such as instruments, valves, junction boxes and other miscellaneous items shall beselected by plant designers to best suit each specific application. The selection will be made in

accordance with the requirements set out in:

This design criteria document

The project automation standard titled Preferred Instrument Equipment List

The above project standards constrain the design processes in the interests of standardization,but leave the final responsibility for selection of suitable technologies and devices with the plantdesigners.

3.6.2 Control System Equipment

Doe Run Peru aim to have a consistent control system implementation across all plants as partof the Doe Run Peru - Projects Management. This objective is expanded elsewhere in this

document, as well as in the project automation standard titled General Automation Philosophy.

To facilitate and progress this objective, early design decisions applicable to all plants havealready been made by Doe Run. (Central control room with common DCS and equipment)

Requirements for control equipment in accordance with the Doe Run decisions are detailed inthe project specification titled Nominated Automation Control System Equipment, and aremandatory for all plants.

4. OPERATIONAL DESIGN CRITERIA

4.1 Design LifeElectrical equipment shall be designed to operate continuously for the design life of the plant inthe conditions typically experienced at the location in which equipment is installed. Plant designlife requirements are nominated in project specifications for each plant.

4.2 Operational Ratings

Equipment operational ratings (such as load current) as shown on drawings shall be worst caseratings taking into account all factors such as process design limits and supply voltagetolerances.


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All components shall be selected and installed such that areas of the plant can operatesimultaneously at the full load rating shown on the drawings under the worst climatic conditions.

The installation shall be arranged to facilitate ease of operation, inspection and maintenanceand shall incorporate all safety measures necessary to protect operating and maintenancepersonnel.

Installation details provided in design documentation shall be strictly in accordance with themanufacturers recommendations.

4.3 Noise

As a minimum, all plant and equipment shall comply with the Peruvian Workplace Health andSafety (Noise) Advisory Standard.

Control valve noise shall be calculated according to the latest edition of the ISA S75.17 orequivalent.

In addition, all continuously operating equipment under normal operating flow conditions shallnot exceed the limits as detailed in the Doe Run Peru Site General Information Specification.

This requirement does not apply during start-up, shutdown or process upsets. Normaloperating flow conditions refer to flows between the minimum and maximum flows stated on thedata sheet.

Noise that is generated as a pure tone (single frequency or narrow bandwidth noise) has anaggravating effect that is significantly greater than an equivalent sound pressure level ofbroadband (multiple frequency) noise, and the acceptable sound pressure level of pure tonenoise is therefore much lower.

Special noise control trim shall be used where necessary to reduce noise to meet the specifiedlevels. Equipment which operates during plant excursions only (such as relief valves orblowdown vents) is not required to meet the design noise limit, however, designers shall use thebest available design practice to minimize noise levels having particular regard for personnelsafety.

4.4 RFI Immunity

Selected instruments shall be RFI immune, complying with SAMA PMC 33.1C (IEC 801-3) orequivalent standard in the frequency range from 20 to 1000 MHz and field intensity up to 10mV/m.

4.5 Immunity from Magnetic Fields

Consideration shall be given to the suitability of equipment selected for installation in areas withextra-ordinarily high magnetic fields.

Equipment with CRT displays and instruments with magnets may not function correctly in thisenvironment. Of particular interest are positioning equipment, reed switches, inductive pick-ups, and magnetic flowmeters. Also of note are weighing systems in which material attractionbetween vessel and support may occur.


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5. GENERAL AUTOMATION DESIGN CRITERIA

5.1 Overview

Compliance with Doe Run Peru standards and specifications is mandatory. Beforecommencement of any work or procurement that deviates from a standard or specification,

approval shall be obtained from Doe Run for that specific deviation.

5.2 Automation Control Systems

This document sets out design guidelines for the control systems, covering such items asequipment housings, system integrity, interface technologies, power supplies, and sparecapacity. For information on equipment selection refer to clause 3.6.2 above.

5.3 Automation Power Supplies

All automation measurement and control system equipment shall be protected against mainspower system disturbances, spikes, voltage fluctuations or loss of supply. Dedicated

Uninterruptible Power Supply (UPS) equipment shall be used for this purpose.

UPS equipment shall be installed for every control room and automation equipment room, andeach UPS shall be sized to provide 30 minutes of operation for the equipment at that location inorder to allow the control system to shut the plant down in an orderly manner.

The standard power supply for automation equipment is 120VAC 60Hz. UPS power will bedistributed as a single phase supply with Active and earthed Neutral connections.

5.4 Instrument Earth Design

Earthing of automation systems has to be carefully designed to avoid introducing unacceptablelevels of electrical noise into measurement and control circuits.

A separate instrument earth circuit is required throughout the plant, segregated from theelectrical safety earth. It is essential to ensure that electrical supply earth fault currents can notflow through the instrument earth.

The instrument earth connections in each equipment room shall be insulated from the normalelectrical earth in the room, and a single electrical connection shall be made from the instrumentearth to an appropriate earthing point.

Automation equipment cabinets and enclosures containing mains powered electrical equipmentshall be earthed to the electrical safety earth.

The instrument earth shall only be used as an instrument signal reference point and to connectinstrument cable screen drain wires.

Details of typical earthing arrangements for automation equipment are shown on projectstandard drawings PS025-MI-0-000-9-0032 (DRP-1-300-27-0032) and PS025-MI-0-000-9-0033(DRP-1-300-27-0033).

5.5 Electrical Control Design

The design of electrical control circuits shall adhere to the requirements detailed in the projectelectrical specifications and associated typical schematic diagrams.


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5.6 Instrument Tag Numbering

Guidelines for the allocation of instrument tag numbers and electrical control signal tag numbersare defined in the project specification titled Instrument Tag Numbering.

5.7 Automation Documentation

The design of automation systems shall follow best industry engineering practices, and shall bewell documented in accordance with project standards. Guidelines for documentation are setout in the automation standard titled Automation System Documentation.

Emphasis shall also be placed on producing support documentation that Doe Run Peru will beable to use to maintain the complex after the construction phase is complete.

5.8 Process Measurement Units

All process data measurement units shall be specified using the engineering units listed in theautomation standard titled Automation System Process Measurement Units, unless specificexceptions are approved by Doe Run Peru. These units shall be used for local gauges,

transmitter indicators and for all definitions and displays throughout the automation controlsystems.

6. AUTOMATION CONTROL SYSTEMS

6.1 Scope

6.1.1 General

The measurement and control equipment to be provided for Doe Run Peru serves the followingfunctions:

Control and monitoring of process plants, including process automation

Control and monitoring of equipment packages, including equipment automation

Execution of safety-related trip and permissive functions

Manual plant shutdowns.

The control systems that provide these functions are discussed in the following sections.

If required by design, standard or regulation, a Fire and Gas System shall be provided as aseparate, segregated system. Fire and Gas System design criteria are not addressed in thisdocument.

6.1.2 Process Control System (Plant Wide Control System)

The primary process control system to be used in all new plants will be a common integratedDistributed Control System (DCS). A network of DCS controllers will effectively form a singleplant wide control system.

The DCS will provide control, monitoring and automation functions for all process plantsincluded in Doe Run Peru.

All plants will use the same DCS equipment, and programming standards will be enforcedacross all plant areas to ensure that the entire DCS has a common look and feel.


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Where the DCS communicates to smart measuring or control equipment that is capable ofimplementing its own control functions, those local control functions shall not be implementedunless they can be programmed and monitored using the standard DCS programming tools.For example, control algorithms may be programmed into Foundation Fieldbus devices directlyfrom the DeltaV DCS.

The use of independent single loop or multiple loop controllers is generally not permitted.

Clause 5.3 of the Doe Run Peru automation standard titled General Automation Philosophydiscusses allowed exceptions.

6.1.3 Equipment Package Control

Individual equipment packages with special requirements may be fitted with a dedicated PLC orother controller to facilitate control. These special requirements are limited to the following.

Applications with high speed scan rate requirements

Motor or equipment protection that cant be safely achieved via the DCS

Specific proprietary control requirements relating to a particular piece of equipment

Each PLC or other local controller will communicate with the DCS to provide consistent

monitoring and supervisory control facilities.

PLC equipment shall be in accordance with the Doe Run Peru automation standard titledAutomation Control System Equipment.

6.1.4 Safety Related Functions

Local equipment safety interlocks and trips may use approved dedicated control equipment orhard-wired circuits in accordance with relevant codes and standards. Examples could includeconveyor pull-wires and burner management systems. These functions shall not beimplemented within the DCS or standard PLC controllers, but they shall be monitored by theDCS or PLC as appropriate so that operators will be aware of the status of the trips andinterlocks.

Where plant hazard identification and hazard analysis studies indicate that the level of riskimposed on personnel and equipment by everyday plant operation is unacceptably high, and adecision is taken to use instrumented functions to provide a calculated level of risk reduction,those instrumented functions shall be implemented in a separate, segregated SafetyInstrumented System in accordance with IEC61508 / IEC61511.

Design criteria for implementation of a Safety Instrumented System are not addressed in thisdocument. If a Safety Instrumented System is required for any plant, a Safety ManagementPlan and all associated documentation shall be prepared in accordance with IEC61508 /IEC61511 before design work commences on any part of the Safety Instrumented System.

Process interlocks and trips provided for equipment protection and to ensure satisfactoryprocess operation shall be implemented in the DCS or PLCs as appropriate.

6.1.5 Manual Plant Shutdowns

Individual process plants will use manual shutdown functions to provide plant operators with anassured means of stopping plant operation. These will be activated by dedicated electricalcircuits initiated from local emergency stop stations or from hard-wired switches in the plantcontrol rooms.


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6.2 Automation Control Equipment Locations

6.2.1 Centralized Control Rooms

Doe Run Peru will provide a centralized control room serving the copper production plant.

The centralized control room will contain the DCS operator workstations plus any associated

equipment required by the operators, and will serve as the normal operating points for theplants.

Project design specifications will establish the minimum requirements for environmentalprotection and controls within the control room.

6.2.2 Local Control Points

Local control points will be provided only where it is necessary to operate plant and equipmentfrom an adjacent location

Where a local control point is installed, a monitoring function shall still be provided in thecentralized control room for that plant.

6.2.3 Automation Equipment Rooms

Within each plant area, dedicated equipment rooms will be provided to house automationequipment. DCS equipment and automation UPS equipment will be installed in each equipmentroom.

Project design specifications will establish the minimum requirements for environmentalprotection and controls within the equipment rooms.

PLC controllers and other local control equipment may be installed in the equipment rooms asappropriate.

6.3 Automation Control System Integrity

6.3.1 General

Overall integrity of a control system has to be considered on a pipe to pipe basis includingmeasuring and control interfaces and cabling as well a the DCS or PLC itself, and it has toinclude consideration of failures and maintenance work outside of the DCS and PLC.

6.3.2 Objectives

Design for control system integrity shall be based on engineering practices that are intended to:

Minimize the risk that protective control functions (functions that are intended to protectpersonnel and equipment from harm in the event of hazardous conditions occurring) can

fail or be disabled in an unsafe way. Unsafe in this context means that the function isdisabled without activating the protection, and without generating an alarm.

Minimize the risk that a single fault anywhere on the control system is capable of stoppingproduction in any plant area.

Provide facilities for carrying out maintenance work and engineering work on the systemwith minimal disruption to production.

Control system redundancy shall be utilized where appropriate to assist in achieving the aboveobjectives. Redundancy is typically applied to critical items where a single fault can affect alarge quantity of IO points and control functions, and more particularly where the time needed torepair the fault could be substantial. Redundancy allows production to continue, and therefore


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allows the fault to be attended to in a reasonable time frame rather than as an emergencymeasure.

6.3.3 Process Control System Redundancy

Within the process control system DCS, redundancy will be applied as follows:

DCS central processing units shall be made redundant.

All DC electrical supplies to DCS components shall be made redundant.

DCS communications links between plant areas shall be made redundant.

Redundant DCS I/O cards shall be used where required.

Redundancy requirements for instrument control loops should be assessed on a case by casebasis with the following as a guide to formulating the specific requirements:

Where an instrument is for indication and warning alarms only no redundancy isrequired.

Where an instrument is part of a control loop, which can be put into manual control modefor a short period without adversely affecting production no redundancy is required.

Where an instrument is critical for plant control and is likely to require frequentmaintenance consider the use of redundant instruments, applying the principle ofMinimum Effective Design.

Power supplies for instrumentation in critical areas shall be designed to a level of redundancythat will allow for maintenance activities and/or breakdowns to take place without loss ofsignificant plant production capacity.

Redundant communications links shall use separate cables and diverse cable routes for eachside of the link so that major physical damage to a cable route is unlikely to affect both sides ofthe communications link.

6.3.4 PLC Control System Redundancy

Redundancy requirements for PLC controllers shall be determined on a case by case basis,using a risk management based approach.

6.3.5 Interface Circuit Integrity

Instrumentation and control interface circuits shall be designed to fail-to-safe conditions suchthat the system and plant shall move to or remain in a safe state after failure of signalconnections, electrical power or instrument air. For example:-

Except for high voltage circuits, all motor stop circuits shall be designed so that the whenthe stop button is pushed the control circuit is opened and the related control relay is de-energized.

All circuits that monitor the health of an item of equipment shall provide a "1" signal

(circuit complete or closed contact) to the monitoring or control equipment. Where there is an interposing relay in such a circuit, the relay shall be energized in the

healthy condition and de-energized in the fault condition.

Where a position limit switch is used to detect if a valve is in a certain position, the switchshall be actuated when the valve is in that position and this shall cause the contact tomove to the closed state. The closed contact ("1") signal shall complete the circuit to thecontrol system input point.

Allowance shall be made for status signals to be transmitted to the DCS for diagnosticand display purposes.


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6.3.6 Manual Shutdown Systems

Manual shutdown systems shall be designed for simplicity and high reliability.

Shutdown systems shall be energized during normal operation, opening a contact to causeshutdown.

All pneumatic components in shutdown systems shall be pressurized during normal plantoperation and shall be vented to cause shutdown.

6.4 Individual Hard-wired Interface Signals

Where individual measurement and control devices have a dedicated and direct electrical signalconnection to the DCS, the signals shall be designed as follows:

Signal Type Connects To Signal Description and Ratings

AI Analogue Input Continuous measuringand indicating devices

2 wire, 4-20 mA, with digital HARTcommunications.

Devices may be powered directly from the4-20 mA loop connection (loop powered),or may require a separate power supplyconnection (field powered 120V AC).

Loop powered devices shall be usedwhere available.

AO Analogue Output Continuous control andindicating devices

2 wire, 4-20 mA, with digital HARTcommunications.

Devices are usually powered directly fromthe 4-20 mA loop connection (looppowered)

DI Digital Input Switches, relay contacts,electrical controlequipment

2 wire, 24VDC, 120 VAC

Devices may provide volt-free contacts(loop powered) or may switch 24VDCsignals (field powered). Loop poweredconnections shall be used whereverpossible, and shall always be used forsignals to the DCS from a PLC.

All signals to DCS digital inputs shall beconnected using two wires per input. Theuse of a common positive or a commonnegative wire for multiple input signals is

not permitted.

Digital pulse inputs to the DCS should notexceed the 75Hz maximum frequencylimit imposed by the DCS input cards.

DO Digital Output Output devices requiringa control voltage shalluse an interposing relay.

DCS outputs will be 24VDC. Theseconnect to relay boards. Each relaycontact rating will be at least 120VAC, 3A.


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Signal Type Connects To Signal Description and Ratings

Solenoids, indicators,relay coils, electricalcontrol equipment

2 wire, 24V for instruments and

2 wire, 120VAC, 3A rating.

Are to be volt-free contact (field powered).

All signals from DCS digital outputs shallbe connected using two wires per output.

6.5 Multiplexed Interface Signals

6.5.1 Electrical Control Equipment

Electrical control equipment may be connected to the DCS using DeviceNet if i t can bedemonstrated that there are cost benefits to the project.

DeviceNet connections to electrical control equipment can be implemented in the following

ways: By direct connections to smart equipment which has a native DeviceNet interface and

DeviceNet device descriptor files provided by the manufacturer. This is the preferredmethod for large or critical drives as it allows device parameters to be viewed bymaintenance personnel using DCS workstations. For example, a smart overload relay ormotor protection relay can provide access to all trip parameters and trip history datawithout requiring any additional DCS programming.

By placing a DeviceNet IO block adjacent to the electrical control equipment in order toprovide discrete signal connections to that equipment. This method may reduce cablingbetween the DCS and the electrical control equipment, but does not allow the electricalcontrol equipment parameters to be viewed from the DCS workstations. This approachwould be appropriate for smaller, non-critical drives.

DeviceNet design shall comply with relevant project specifications and standard drawings.

6.5.2 DCS Communications Links to PLC Controllers

Communications protocols and design criteria will be established for each individual PLCcontroller once exact model and application details are known. Available physical layercommunications protocols are:

RS-232 (This protocol is least preferred and shall not be used unless there is no choice)

RS-485

Ethernet (TCP/IP Ethernet over optical fibre cables is preferred by Doe Run Peru andshall be used where appropriate.)

6.6 Control Equipment Enclosures

DCS and PLC equipment that is to be housed in automation equipment rooms shall be installedin freestanding fully enclosed cabinets. All equipment installed in the cabinets shall be fullyaccessible and removable for maintenance purposes.

Control equipment that is mounted in the field adjacent to the equipment under control shall bemounted in enclosures designed to protect the control equipment against the environmentalconditions prevailing at that location.


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Enclosure design shall comply with the enclosure requirements defined in the automationstandard titled Automation Control System Equipment.

6.7 Equipment Cable Connections

All equipment enclosures shall provide adequate cable entry space for the intended usage.

Cable entry shall be by removable metal cable gland plates or alternative cable clampingarrangements that provide support for the cable outer sheath and seal the cable entry pointagainst ingress of dust, contaminants and vermin.

Terminals for connection of instrument and electrical cables shall be either a screw type or aspring clamp type in accordance with the automation standard titled Preferred Equipment List.Insulation displacement technology shall not be used.

Note: These requirements apply only to the termination points for field cabling, not to internalequipment wiring which may use any appropriate technology. Individual cores of field cablesmay be disconnected and reconnected many times over the life of the plant

6.8 Spare Capacity

The following spares guidelines shall be applied to each DCS controller and PLC controller:

Each controller shall have a spare capacity of 20% installed IO for discrete hardwiredinterface signals. This shall be interpreted as having adequate spare channels on IOmodules installed at that location to allow the number of points of each type of IO (AI, AO,DI or DO) to increase by 20%.

Each controller shall have at least 20% spare slots for IO modules, and shall have aminimum of three (3) spare slots.

Controller capacity (memory, processor capability, power supplies, ventilation) shall beadequate to cater for the additional IO points and modules should the above sparecapacity be used.

Marshalling cabinets shall have adequate capacity to allow termination of the additional

IO points should the above spare capacity be used.

7. AUTOMATION SYSTEM CABLING

7.1 Automation Cabling Overview

The selection of cables and the preferred cable size ranges for automation systems are definedin the automation standard titled Automation Cable Type List.

This document sets out design guidelines for the installation, termination and protection ofcables.

7.2 Automation Cable Arrangements

Dedicated cabling shall be used for all automation services, including all optical fibrecommunications network cabling, and the cabling shall generally run directly from controlsystems to measuring and control equipment or electrical control equipment as required.

Automation signals of different voltage levels shall be segregated into separate cables. Underno circumstances shall a cable carrying 120VAC on any core be used for 24VDC digital oranalogue signals.


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Where appropriate, instrument junction boxes shall be provided to marshal the fieldinstrumentation cabling to convenient locations on each installation package. Junction boxlocation shall be selected to minimize the length of the instrument cables. Note that junctionboxes used for marshalling are not mandatory, and it is acceptable to run instrument cablesdirectly to DCS cabinets in the automation equipment rooms, particularly for short cable runs.However the use of a single multi-pair cable to replace multiple single pair cables may offer thefollowing advantages in most cases:

Lower capital and installation cost

Easier addition of new circuits in the future

Easier cable gland installation in DCS cabinets, which typically have limited cableglanding space available.

Instrument junction boxes shall be segregated for 24VDC and120VAC signals, and no generalpower supplies shall be connected to any instrument junction boxes. No process or servicesfluids other than instrument air shall be reticulated within instrument junction boxes.

Plant designers may choose to segregate 4 to 20 mA analogue instrument signals and 24VDCdigital instrument signals into separate cables and junction boxes for practical reasons, but thisis not mandatory.

7.3 Cable Termination Design

All pairs (including spare or unused pairs) shall be identified using an approved wire markingsystem.

All wires shall be terminated with insulated bootlace ferrules of the correct size crimped with aratchet crimping tool. Two conductors may be terminated in a single terminal provided that theyare crimped into a single double-wire bootlace ferrule of the correct size. Space of 70mmminimum shall be left between the terminal strip and ducting to enable the wire identificationferrules to be clearly visible.

The screen or drain wire for individual pairs and the overall cable screen shall be connected tothe instrument earth at the DCS marshalling cabinet end only. The continuity of the cablescreen, (drain wires) shall be made continuous through junction box terminals. The drain wireshall be cut out and insulated with heat shrink tubing to protect against inadvertent earthing atthe field instrument end.

7.4 Spare Cable Capacity

A minimum of twenty percent spare capacity shall be allowed for in the main runs of multi-coreand multi-pair cables.

Termination design shall allow for every spare core / pair to be terminated at each end of thecable.

7.5 Cable Installation Design

Design criteria for detailed cable installation requirements and cable protection requirementsare not included in the scope of this document, but a brief summary of requirements ispresented below. Project specifications and standard drawings shall be prepared as required todetail the requirements for cable installation design. These documents and drawings shall beused by Doe Run Peru to prepare the detailed installation documentation for the installationcontractor.

All cables associated with the field instrumentation and control system that are installed outsideof control rooms, auxiliary equipment rooms or electrical switch rooms require protection against


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possible physical damage. The cable protection may be implemented by either of the followingmeans:

By installing cables in flexible conduits, steel conduits or ducts in all areas where thecables are not adequately protected by the cable support systems, for example by metalcable trays.

Cables that are confined to control rooms, automation equipment rooms or electrical

switchrooms shall be installed in such a manner that the risk of physical damage is minimized.

Cables shall be installed away from sources of heat likely to raise the temperature of the cablesabove 50C.

24 VDC instrument cables shall be segregated from power cables. In particular, all instrumentcabling shall be installed so that it is well isolated from any power cabling associated withvariable speed drives.

It is essential that during the cable termination process, that screen off-cuts are managed andcollected, and that all screens are sealed with heat shrink tubing at cable ends.

8. INSTRUMENTATION REQUIREMENTS

8.1 General

Field instrumentation shall comply with the relevant requirements of the Doe Run Peruautomation standards, as well as all relevant Peruvian regulations and standards. Refer clause3.1 above.

In general, unless otherwise specified, all instrumentation regardless of location shall bedesigned for the ambient temperature range specified for the site. Refer clause 3.4 above.This requirement may be relaxed in special cases, for example in air-conditioned rooms.

All instruments shall be supplied fully assembled where possible, factory calibrated, set-up and

configured with all parameters so they are ready for operation. The tag number and servicedescription shall be included in the configured parameters.

The materials of construction of all instruments shall be suitable for the specific processrequirements, and shall be detailed on instrument data sheets during the design process.

Transmitters shall be considered for process alarm and trip applications, taking into accountminimum effective design.

It should be noted that all process controls will be implemented in the plant wide DCS, and thatthe use of independent single loop or multiple loop controllers is generally not permitted.Clause 5.3 of the automation standard titled General Automation Philosophy discussesallowed exceptions.

8.2 Instrument Nameplates

All instrumentation including actuated valves shall be identified with the manufacturersstandard, permanently attached metal nameplate. Stainless steel nameplates are preferred.The means of attaching the nameplate shall be by stainless steel screws or rivets.

Aluminum nameplates shall not be used anywhere within the copper refinery building, and thisrequirement shall be stated on all instrument data sheets issued for the copper refinery.

Nameplates shall show the manufacturer, model number, serial number, size, rating, date ofmanufacture and other necessary equipment details.


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Nameplates on control valves shall state the manufacturer, model, serial number, air supplypressure range, valve design temperature and pressure, body size and material, trim size andmaterial, trim characteristic, Cv, actuator spring range and bench set.

All explosion-protected (Ex) items of equipment shall be fitted with permanently attachedstainless steel labels. Labeling shall be in accordance with Peruvian Standards as discussed inclause 3.5 above.

8.3 Instrument Tag Labels

All instrumentation including actuated valves shall be fitted with an additional, permanentlyattached 316SS label complete with the instrument tag number engraved or stamped thereon.The label shall be attached by flexible stranded stainless steel wire, screws, rivets or bolts to theinstrument or control valve body. The label shall be removable to allow for instrumentreplacement.

For stand-mounted instruments, a similar label shall be permanently fastened to the instrumentstand.

Typical label details are shown on the project standard drawing titled Instrument Tag Labels.

8.4 Calibration Certificates

Each instrument that can transmit an electronic signal to the DCS shall be supplied with its owncalibration certificate showing the serial number of the instrument, tag number, purchase orderdata, equipment name, calibration details, description of the tests performed, date of calibrationtest, place of calibration and signature of person conducting the tests. Calibration certificatesshall be in the English language.

8.5 Process Connections and Instrument Air Supply Connections

Doe Run Peru has specified ANSI flanges, piping and pipe fitt ings, with NPT connectors.

For each plant area, instrument connections shall comply with the specifications and ratings inuse by the plant designer process, mechanical and piping groups.

The instrument process connections shall match the piping/vessel process connections for eachtype of instrument. Reducers may be required on some of the screwed connections. Standardinstrument hookup drawings shall be prepared for each type of instrument to detail the requiredprocess connections and instrument air connections.

8.6 Electrical Connections

Cable gland entries for instrument signal and electrical connections shall have M20 1.5mmfemale threads. Where this thread type is not available with instrumentation then suitablethread adaptors shall be used to connect the cable gland to the instrument connection.

For instruments that are supplied with an integral flexible cable, an in-line junction box shall beused to connect the flexible cable to the main cable.

8.7 Equipment Enclosures

The minimum ingress protection classification for field-mounted instrumentation isIP65/NEMA4X to IEC 60529. Field instrumentation shall be rated to IP66/NEMA4X wheninstalled in areas that can be hosed down by plant operators.


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Junction boxes shall have external mounting tabs so that the enclosure IP/NEMA rating can notbe affected by mounting bolt penetrations in the sealed section of the enclosure.

Complex process stream analyzer systems shall as a minimum comply with the enclosurerequirements defined in the automation standard titled Automation Control System Equipment.The following additional requirements shall also be applied:

Analyzers which are critical to facility operation or have an ambient temperature limit of

40C shall be installed in air conditioned houses o r cabinets. All other analyzers shall besupplied with forced air ventilation. Cooling and ventilation shall be provided by dualredundant units.

These enclosures shall be located as close to the process sample points as practical.More than one analyzer measuring and sample system may be installed in a singleenclosure if the sample line length is within the analyzer manufacturer's specifications.

8.8 Reverse Polarity

Each instrument shall be immune to damage caused by reverse polarity connection and outputshort/open circuit.

8.9 Instrument Isolation

All instruments connected via process impulse tubing shall be provided with a primary isolationdevice, installed as close as possible to the process, and also with a secondary isolation deviceinstalled as close as possible to the instrument.

The secondary isolation device shall be delivered to site with the instrument, and may be in theform of a manufacturers standard valve manifold. This device shall incorporate a vent/drainfacility to enable the impulse tubing to be depressurized safely.

The primary isolation device shall form part of the process piping design.

For instruments connected directly to the process, the isolation and vent/drain valves shall be

provided to facilitate maintenance, but shall not affect the instrument performance.

8.10 Calibrated Range

The accuracy, resolution and repeatability of the instrument shall be taken into account whendeciding on the number of digits to be displayed on indicator panels and operator stations.

Indicators shall not needlessly display digits that are less than the measurable accuracy orprecision of the instrument.

Meter scales and instrument spans shall be a decimal multiple of 1, 1.2, 1.5, 2, 2.5, 3, 4, 5, 6, 8and 10. In the instance of the meter not directly measuring the displayed parameter (eg,differential pressure being measured to indicate flow), the scale of the displayed parameter shall

be selected from the meter scales listed above and the measuring instrument range shall bescaled to suit.

8.11 Instrument Mounting

Local indicator instrumentation such as dial thermometers, pressure gauges shall be plainlyvisible from grade or platform.

All instruments (including valves) shall be installed to facil itate maintenance, whereverpracticable, using the following criteria:


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For the purpose of this section, readily accessible shall mean accessible for operation,maintenance or replacement from grade or permanently installed platforms, withoutrequiring the use of scaffolding, portable ladders or machinery such as extendable mobilework platforms.

Where an instrument system comprises a primary element mounted in a process line orvessel, and a detached amplifier, transmitter or control device connected by sealedcapillary tubing, impulse tubing or cable, then the detached device shall be mounted so

that it is readily accessible, even if the sensor element cannot be practically mounted inan accessible location. If the primary isolation valves at the primary element are notreadily accessible, then additional readily accessible isolation valves shall be provided inthe impulse tubing. If the instrument is f itted with an instrument manifold, the valves in themanifold may be used as isolation valves. However, additional valves may be required ifthe process fluid requires double-block-and-bleed isolation.

Instruments which require operations or maintenance access weekly or more frequently,and instruments which are critical to process operations or safety shall be located so thatthey are readily accessible.

The preferred mounting arrangement for instruments and ancillary equipment whereappropriate shall be 50mm pipe stands as detailed in the project standard hook updrawings.

Instruments which require operations or maintenance access daily or more frequently, orwhich repair or scheduled maintenance is labour intensive or requires the use of heavyhand-carried tools, shall be readily accessible via a stairway, (i.e. access via a fixedladder is not acceptable in such cases).

Instruments which do not meet the criteria above shall be located to give the bestpossible access within project cost constraints.

Instrument mounting brackets and associated fasteners shall be 316 SS as standard, butalternative materials may be specified to suit project requirements. Mounting brackets shall beincluded in the supply of all instruments with exception of line/flange mounted instruments.

Care shall be taken with stainless steel coming in contact with galvanized metal. Galvanicaction between the two dissimilar metals causes corrosion.

Consideration shall be given to the protection of instruments in areas prone to spillage. Theinstruments may be fitted with suitable enclosures or protective bag covers with drawstrings.(This still allows the use of local indicators by temporarily removing the bag when required).

Sunshades shall be fitted to all instruments exposed to direct sunlight if the maximum operatingtemperature of the instrument will be exceeded. Details of construction for the sunshades shallbe included on the project standard instrument hookup drawings.

Instrument stands shall be positioned such that the stands and instruments do not intrude intowalkways. Instruments and any ancillary equipment shall not be mounted on handrails.

In general, remote mounted instruments, junction boxes and local panels shall be mounted atthe outside edges of each plant envelope, where practicable. This requirement is particularlyapplicable to corrosive areas.

All equipment shall be installed strictly in accordance with the manufacturers instructions.

8.12 Instrument Air Supply

All instrumentation and control valves requiring an air supply shall be supplied from aninstrument-quality air reticulation system.

The instrument air supply system shall include compressors, dryers and filters capable ofsupplying air to the following specifications


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Maximum dew point of -5C at line pressure

Maximum particle size of 3 microns in the air stream

The maximum total oil or hydrocarbon content, exclusive of non-condensables, shall beas close to zero as possible, and under no circumstances shall it exceed 1 part permillion (ppm) on either a weight or a volume basis.

The capacity of the instrument air supply system shall be such that in the event of compressorfailure, sufficient air is available in reserve to operate the instrumentation enabling the plant toshutdown safely. The minimum acceptable hold-up time is 30 minutes. At the end of this time,the air pressure shall not be lower than the specified minimum pressure.

Air receivers in each process area shall be individually sized to cater for the reserve capacityrequired.

The instrument air supply system and piping shall be designed to meet the followingrequirements, measured at any point in the system:

Nominal pressure 680 kPa(G)

Maximum pressure 800 kPa(G)

Minimum pressure 500 kPa(G)

All pneumatic instrumentation and actuated valves shall be designed for service with aninstrument air supply which may vary in service over the pressure range specified above.

All instrument air consumers shall be fitted with a dedicated air filter/regulator with manual drain.The air/filter regulator shall remove water, oil and sediment to the specification required by theair consumer. A nominal 5 micron filter element is generally acceptable. The sediment bowland cage shall be constructed from a non-metallic or corrosion resistant material. The regulatorsetting shall be selected to suit each application in accordance with supply pressurerequirements as shown on instrument data sheets.

Each instrument air consumer shall be supplied via a dedicated lockable isolating ball valve.Each ball valve shall be fitted with a stainless steel tag stamped with the instrument air

consumer tag number.

In general, where multiple air consumers exist on a control valve, a single air filter/regulator andisolation ball valve shall service all components.

The instrument air distribution piping shall be such that the air take-off points are located on thetop of headers and manifolds. Drain valves shall be located at the lowest points.

8.13 Instrument Piping and Tubing

Process impulse tubing and instrument air supply tubing shall be bare 316-grade stainless steelunless otherwise specified or the process fluid or the process ambient conditions dictateotherwise.

Process impulse tubing shall be O.D.

All threads shall be NPT.

The maximum length of any impulse tubing shall be 15 metres. All impulse lines shall beinstalled with a minimum gradient of one in one hundred (I in 100) to ensure that the entire lineis self-draining. Impulse tubing shall not be used to support or brace instruments.

Plastic tubing shall not be used for air supplies to actuated valves or instruments, even inareas of high vibration. A short flexible braided 316-grade stainless steel, or project specificmaterial, hose shall be used.


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In extreme acid/corrosive environments, instrument air tubing shall be (black) flame retardingpolyethylene or PTFE unless the environmental conditions require the use of different materials.Special consideration shall be given to areas with ammonia, chlorine, chlorides and hydrochloricacid.

Pneumatic equipment that may require frequent disconnecting for maintenance purposes shallbe fitted with flexible braided 316 stainless steel hoses unless the process fluid or the process

ambient conditions dictate otherwise. Stainless steel fittings shall be 316-grade.

Stainless steel valves and compression fittings shall be used unless the process fluid or theprocess ambient conditions dictate otherwise. Tubing connections shall utilize two ferrulemechanical grip compression fittings.

Where local air distribution manifolds are used, a minimum spare outlet capacity of 25% and adrain point with a valve shall be provided.

All personnel installing stainless steel fittings and tubing shall have appropriate competencycertificates from the manufacturer to carry out such work.

9. MEASUREMENT TECHNOLOGIES

9.1 Process Analyzers

9.1.1 General

Process analyzers cover a wide range of measurements. The specific requirements aredetailed on the instrument data sheet and project specific Standard Specifications. Generalrequirements include the following:

pH, ORP and Conductivity Probes shall be self-cleaning where practically achievable.

Non-extractive sampling methods of analysis shall be employed wherever possible.

Design shall allow simple, automated calibration procedures.

Process analyzers shall be supplied complete with any necessary sampling and sampleconditioning systems.

All analyzers are to be completely piped, interconnected, and checked out for properfunctional operating condition.

Process analyzers shall be selected which do not require reagents, calibration gasesand/or liquids, wherever possible.

Necessary reagents, calibration gases and/or liquids required for at least twelve monthsoperation shall be part of a purchased package.

Where possible, each analyzer shall be supplied with valves, fittings and othercomponents that are required to facilitate on-line calibration of the analyzer.

Field mounted analyzers shall be of corrosion resistant material, weatherproofconstruction and suitable for outdoor installation.

The output signal shall be galvanically isolated 4-20 mA (linear) for single componentanalysis. Alternatively, for multiple component analysis, a serial output may beconsidered as the method of data transmission to the Plant Wide Control System. Wherea multi-component analyzer is used for the purpose of process control, serialcommunications shall not be used unless redundant communications paths can beimplemented.

All analyzer transmitters shall incorporate an integral mounted indicator, scaled inappropriate engineering units.


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9.1.2 Calibration Equipment for Analyzers

All necessary calibration and operating gases including gas cylinders and regulators shall beprovided.

Analyzers requiring gases for continuous operation shall be provided with dual facilities foruninterrupted service.

Calibration standards and facilities shall be supplied for zero and span check where specified.

Protected outdoor storage racks adjacent to the analyzer houses shall be provided for thecarrier and calibration gas cylinders and their associated regulators. Process sample regulatorsshall also be located on the outside of the analyzer houses.

9.1.3 Sample System for Analyzers

The sample systems shall be designed to deliver clean, representative samples to the analyzersat the proper temperatures, pressures, physical conditions and flow rates.

Wetted component materials shall be selected to minimize contamination and corrosion.

Appropriate measures shall be taken to prevent plugging of sample lines due to freezing,condensation or solids.

Where sample recovery systems are required, provision for items such as drains shall be madein the building design.

Transportation time from sample point to analyzer shall be designed to be less than two minutesfor chromatographs and less than one minute for other analyzer types. Fast circulating loopsand/or bypass lines shall be used to achieve fast response times.

For gas samples, the pressure shall be reduced at the sampling point to increase the velocitythrough the sample system and reduce time lag.

All sample and bypass lines shall have flow indicators, such as variable area flowmeters.

Adequate facilities shall be provided to protect against unwanted backflow, overpressure, orother abnormal conditions.

When sample conditioning components require heating, they shall be located inside a heatedand insulated cabinet or enclosure.

The sampling and sample conditioning system shall be designed, supplied and commissionedby the analyzer supplier to suit the specific analyzer application.

Sampling and sample conditioning systems shall be constructed from materials that shall suitthe process conditions.

The sample shall be metered, pressure regulated, cooled, cleaned or treated as required to

obtain a satisfactory sample for the analyzer under all process conditions.

The sampling system shall be designed for reliability, ready access for maintenance andservice.

9.1.4 Electrical Requirements for Analyzers

Normally, the control circuits of the analyzer should be powered from an automation equipmentroom UPS (Uninterruptible Power System). Each analyzer shall have an over current protectivedevice (a magnetic type circuit switch or a fuse). Local disconnect switches shall also be


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provided so that the instruments can be safely serviced. Cabinet heaters, circulating pumpmotors and other devices which draw relatively high currents may be powered locally.

9.2 Nucleonic Instruments

9.2.1 General

Nucleonic instruments shall be considered where no other type of instrument will performadequately.

Radiation source and source containers shall meet the safety requirements of ISO 2919 Radiation Protection, Sealed Radioactive Sources. In addition all equipment (including radiationsource capsule, container and label) offered must comply with the national and regionalradiation safety requirements, Statuary Authorities and Regulations.

Nucleonic instruments shall be selected and positioned taking into account that non-destructivetesting with X-rays can interfere with their operation.

Where necessary, external shielding shall be provided to avoid cross-interference ofinstruments or disruption to operations and maintenance activities.

All necessary details and drawings required to support licence applications for site installationshall be provided with each instrument. All necessary warning signs and notices shall beincluded with each instrument.

Test certificates shall be supplied with each radiation source.

An approved wipe test method to verify source capsule integrity, as required by any nationaland regional conditions of licence, shall be provided with the instrument.

On pipeline applications 50 NB and greater, clamp on type units shall be used. On pipelinessize DN50 or less, Z type mounting arrangement where the beam is concentric with the fluidflow path shall be used. The source and detector shall be installed in such a way that the pipeis always full of liquid (i.e., vertical or near-vertical pipe, with upward flow).

For density measurement, facilities shall be included in the process piping, near the gauge, tothe Suppliers specifications in order to take a reliable sample for periodic calibration checks.

Lead absorber plates shall be supplied, if required for calibration of the instrument.

Automatic source decay compensation shall be provided.

A suitable source half-life of at least 10 years shall be selected to make the installationspractical, however oversizing shall be avoided. This involves a low activity source with a highsensitivity detector.

Nucleonic source canisters shall be provided with hand-operated shutters for safety isolation.Isolation shutters shall incorporate provision for padlocking, instead of or in addition to any built-

in key locking mechanism. Isolation shutters shall be provided with limit switches, arranged sothat a limit switch is closed when the corresponding shutter is fully engaged in the "normalservice" position. The preferred type of limit switch is an inductive proximity switch. Shutterposition switches shall be wired to DCS inputs.

Source, detector and transmitter housing shall be constructed of corrosion resistant suitable forplant conditions, weatherproof and suitable for outdoor mounting.

Detailed source sizing calculations stating the vessel wall thickness and lining shall be supplied.

All necessary calibration equipment shall be supplied with each instrument.


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Warning signs shall be provided in accordance with the local regulatory codes and standards.

Nucleonic sources shall be able to be returned to the Supplier for disposal when expired.

The instrument supply shall include delivery to site.

9.3 Flow

9.3.1 General

All instruments will be specified with local indicators wherever practical.

9.3.2 Liquid

Magnetic flowmeters shall be used for liquid, where practicable. For liquid applications withsuspended solids, the ideal velocity through the flow tube shall be in the range of 1.5 to 3 m persecond to prevent sedimentation of solids and minimize wear on the liner.

Clean or low conductivity liquids and steam may be measured by vortex shedding meter.Vortex meters shall not be used where the piping may be subjected to vibration. It should benoted that vortex meters require a minimum flow to produce a signal. This may not beacceptable for some applications during start-up and shutdown.

Averaging pitot tubes or orifice plates may be used as the primary measuring element on largediameter clean liquid pipelines.

Coriolis meters shall be used for fuel oil and distillate flow measurements,

Custody transfer metering shall be accomplished using coriolis flowmeters on process fluid.

In-line variable area flowmeters (rotameters) with needle valve controls shall only be used onnon-critical purging and injecting services, eg, pump seals.

Transit-time ultrasonic flow meters may be used in special situations where their uniqueadvantages are required (eg, very high temperatures, non-contact measurement).

9.3.3 Gas and Steam

Averaging pitot tubes or orifice plates may be used as the primary measuring element on largediameter piping with clean gas or steam flows. For mass flow measurement on gas flows usingpressure differential techniques, multi-variable transmitters with automatic temperature andpressure compensation may be used.

Clean gas or steam flow may be measured by the Vortex shedding meter. Vortex meters shallnot be used where the piping may be subjected to vibration. It should be noted that vortexmeters require a minimum flow to produce a signal. This may not be acceptable for someapplications during start-up and shutdown.

Doe Run Peru prefers the use of Vortex meters where possible.

The Thermal Dispersion mass flow measurement technique may be applied for flowmeasurement of clean, homogeneous gases that are relatively constant in composition. Theseinstruments shall be mounted with marks to indicate correct orientation of the device. Multi-point units should be used wherever possible to ensure improved measurement accuracy.

Flow elements such as flow nozzle or venturi may be used where high capacity or high-pressure recovery is required. The venturi nozzle should be considered in high vacuumapplications where high pressure recovery and low pressure drop is required.


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In-line variable area flowmeters (rotameters) with needle valve controls may only be used onnon-critical purging and injecting services.

Magnetic flowmeters are not acceptable for gas and steam services.

9.3.4 Flow Meter Installation

Due consideration must be made for the effects of turbulence caused by the piping, includingVSD pumps and control valves.

When the flow is controlled by a variable speed pump, the flowmeter shall be installed after andas close as practical to the pump.

When the flow is controlled by a control valve, the flowmeter shall be installed upstream of andas close as practical to the valve.

For flow meters in vertical pipelines, flow direction is preferably downward for wet gas orsaturated steam, and upwards for liquids.

9.3.5 DP Transmitter Installation

Differential pressure transmitters used with orifice plates shall be remote mounted.

Differential pressure transmitters used with averaging pitot tubes can be mounted close coupled, if the flow element allows direct connection of the transmitter, and it is practicable andmaintainable.

Remote mounted transmitters shall be located as close as practically possible to theirassociated primary element.

Tapping points shall have rod-out facilities where solids could be present in the process streamwith consideration to provide continuous purge of the sensing element.

Seals and condensate pots shall be used where necessary.

9.3.6 Flow Meter Orifice Plates

The standard primary element shall be square edge concentric orifice plate in accordance withISO 5167-2, except that a quadrant edge orifice, in accordance with BS 1042, shall be usedwhen the Reynolds number is below 20,000.

Flange taps shall be used. D-D/2 taps may be used if the line size is 400 NB or larger.

Orifice flanges shall have a minimum rating of 300#.

Material of orifice plates shall be type 316 stainless steel, unless special materials are requiredby the process fluid.

Orifice plates shall have the instrument tag number, plate material, flow direction identification,bore size and line number clearly stamped on the upstream side of the plate handle.

Straight-run lengths of pipe upstream and downstream of orifice plate installations and orificeplate installations shall conform to the requirements defined in ISO 5167-2 and as required tomeet the specified accuracy.

Reduced straight-run lengths shall only be considered for lower-accuracy applications or wherepipe work constraints prevent the required straight-run lengths.

The orifice plate shall be installed in a manner such that it will always measure a full pipe flow.


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Orifice meter differential range shall be selected so that the d/D ratio exceeds 0.2 and is lessthan 0.7.

Orifice meters, other than integral orifice, shall not be used on pipelines smaller than DN50 mm.Alternative flow meters shall be considered for line sizes greater than 200 mm for clean gas orsteam service.

All integral orifice transmitter assemblies shall have flanged end connections as indicated on thedata sheets. Where there is a requirement for minimum lengths of straight pipe upstream anddownstream of the integral orifice transmitter flanges, a complete assembly comprisingtransmitter and straight pipe lengths shall be supplied.

9.3.7 Differential Pressure Flow Measurement

Square root extraction for flow applications shall be configured in the DCS.

All differential pressure transmitters shall be fitted with an instrument valve manifold asapplicable, except where diaphragm seals are used.

In general, a 3-valve manifold shall be used.

A 5-valve manifold shall be used where toxic or hazardous process gases or fluids need to bedrained to a safe location.

Where impulse lines need to be filled, small valves shall be fitted to the transmitter body in placeof the drain plugs. The valve materials shall suit the process fluids.

The meter range shall be selected in accordance with the following:

For differential pressure flowmeters, normal flow rate shall be between 70% and 80% ofinstrument span, provided that anticipated minimum and maximum flowrates will be between30% and 95% of capacity.

For range ability larger than 30% to 95%, an alternative method of flow measurement shall beused.

For variable area meters, the normal flowrate shall be between 50% and 80% of capacity.Variable area flowmeters shall be selected from the suppliers standard range.

For line sizes smaller than 50 NB, an integral orifice meter shall generally be used.

Averaging pitot tubes shall use screwed connections. Note: The process connection size isdetermined by pipe size and process conditions. Consideration shall be given to the use of theretractable style, which enables them to be removed for maintenance while the plant is on line.

Differential pressure ranges for orifice plate applications shall be selected from a set of standardranges in the order of precedence indicated:

25 kPa

50 kPa or 10 kPa

100 kPa or 5 kPa

9.3.8 Magnetic Flow Instruments

The following issues shall be considered when installing magnetic flow meters in non-verticalpipes:

Accumulation of silt and scale in low-lying piping.

Accumulation of gas or vapor bubbles in the top of the pipe.


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Measurement of 2-phase fluid flows can be affected by material segregation.

Gravity could affect the distribution of flow velocities across the electrode axes.

Magnetic flowmeters are acceptable for pipe sizes 200 mm and larger, in applications where thereduced instrument accuracy can be tolerated.

Magnetic flowmeters shall not be located in pipes that drain when the flow stops. Where this isnot possible, for example some slurry lines, meters with empty pipe detection or suppressionlogic should be considered to prevent the flow indication becoming invalid.

Flowmeters shall be supplied with remote converters when either:

the local indicator can not be read from floor or grade level, or

the flowmeter cannot be accessed for maintenance from floor or grade level.

Elsewhere, the converter shall be integral to the flowmeter body.

The converters for all hazardous area installations shall be remote to the flowmeter body.

If appropriate, wafer body flowmeters shall be used for applications where the line size is 200

mm or less in diameter. Flanged flowmeters shall be used where the line size is 250 mmdiameter or greater.

9.3.9 Vortex Flowmeters

Vortex flowmeters have a large turn down and can be used on a wide range of clean fluids, i.e.liquids, gases, steam. They shall not be used on scaling services, pulsating flow or wherevibration is present. With sizing, the upstream pressure should be relatively constant.

Vortex meters are not suitable for two-phase flow measurement, including wet gas or wetsteam.

All vortex meters shall have a local indicator.

Insertion vortex meters shall not be used.

Vortex meters used for SIS signals shall have sensors replaceable while in service. Meters withdual sensors may be considered.

Wafer body flowmeters shall be used for applications where the line size is 200 mm or less indiameter.

9.4 Level

9.4.1 General


9.4.2 Design and Selection of Level Instruments

The use of non-contact level measuring devices for liquids shall be used wherever possible.

To prevent ringing or degraded performance, non-contact level instruments shall be selectedand installed so the front face of the instrument protrudes beyond the lower rim of the nozzle inwhich they are installed.


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9.4.3 Ultrasonic

Ultrasonic devices are not suitable for vacuum environments.

Ultrasonic level sensors may be used for measurement of level in material handling applicationsand vented vessels, tanks and sumps containing slurries. The rate of change of level should beconsidered when selecting ultrasonic instruments. Other methods may be necessary inapplications where foam/froth, condensation, dusts or steams are prevalent. Transducers shallbe selected for adequate acoustic power under the most arduous process conditions.

Only ultrasonic level instruments with built in temperature measurement and compensation shallbe used.

Wherever possible, the process connection for top-mounted ultrasonic level transmitters shallbe either 80 mm or 150mm flanged. Smaller loop-powered units used for non-criticalapplications such as sump level may use alternative mounting arrangements.

9.4.4 Radar

Radar level devices may be used on bulk material handling, vented or pressurized vessels,vacuum vessels, tanks and sumps. They shall be used for applications where steaming,

foaming/froth, dust, condensation and where the potential for gas or product vaporization mayoccur. They may be used in extremely dusty applications and where dust bursts are presentduring product filling. The sensor shall be fitted with a horn or antenna, manufactured frommaterial chemically compatible with the process environment. Loop powered devices shall beused, where practicable.

The process connection for top-mounted radar level transmitters is 80 mm or 150mm flanged. Inspecial cases, a larger flange may be used as required.

9.4.5 Differential Pressure Level

The DP method of level measurement may be used where ultrasonic and radar is not suitable.

Where a sealing fluid (eg, glycerine) would be required for the wet leg, remote diaphragm seals

shall be considered.

Differential pressure transmitters without diaphragm seals, shall be fitted with 3-valve or 5-valvemanifolds.

A 5-valve manifold shall be used where toxic or hazardous process gases or fluids need to bedrained to a safe location. On tanks and vessels, differential pressure transmitters fitted withintegral or remote diaphragm seals shall be 80 mm flanged.

On tanks and vessels, differential pressure transmitters with 12mm tube connections shall havea 50 mm isolation valve connection. Suitable adapters shall be used.

Bubble tube devices shall be avoided unless other methods are not practical. Depending on theduty, water purging may be required.

9.4.6 Capacitance, Admittance and RF Types

Capacitance and related types of level detector are generally not acceptable. They may beused only in applications where a special case can be made for their use and with the approvalof Doe Run Peru.

9.4.7 Magnetic Level Gauge

Magnetically-coupled float level gauges are acceptable where sight glasses are not appropriate,for example where clouding of the sight tube would occur.


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The style of level indicator used shall be the sealed float-type, enclosed within a stainless steelcage or material suitable for the process fluid.

The sealed float shall be magnetically coupled to the level indication assembly that is attachedto the side of the cage.

The indication assembly shall be field adjustable to enable the scale to be viewed from the most

convenient orientation. The indicator shall be a series of interlocked (to prevent over-rotation)rotating flappers contained within a hermetically sealed case and shall range fully betweentapping points.

Process wetted materials shall be 316 stainless steel minimum unless the process fluidproperties require the use of alternative materials. Magnetic level gauge and sight glass levelgauges shall have 50 mm flanges.

Drain and vent valves shall be fitted to all level gauges.

When designed, the vent and drain valves on level gauges shall be accessible from the samefloor where the level gauge is located. Sufficient space shall be left between the top and bottomof the gauge and the floor grating to allow for maintenance.

External level bridles shall have 80 mm flanges for the main process connections. Refer to thebridle connected instruments for their process connections.

9.4.8 Level Switches

Switches shall be used only for low integrity and clean services. Transmitters are preferred forgeneral process service.

Level switch devices shall use one or more of the following methods of measurement:

Internal float

External cage float/displacer

Vibrating fork

Capacitance

Ultrasonic

Conductivity

Rotary type

Microwave

Nuclear

Electrical switches shall have a contact rating of 24 VDC 2A minimum with SPDT contacts.

Internal float switches (side or top entry) mounted on tanks or vessels shall be 80 mm flanged.

The preferred process connection for other level switches shall be 50 mm flanged.

9.5 Pressure

9.5.1 General


Unless otherwise specified the process wetted parts shall be 316 stainless steel.


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Pressure ranges shall be selected so that the normal operating pressure is between 50% and70% of full scale or instrument span with due regard for maximum pressure expected.

Process connections for pressure tapping points on non-lined pipes shall be threaded.

Process connection for pressure instruments on glass-lined and PTFE-lined pipes shall be 50mm flanged.

The use of pneumatically or hydraulically-operated pressure controllers is not acceptable.

Mercury filled pressure instruments are not acceptable.

9.5.2 Pressure Gauges

Unless otherwise specified pressure gauges shall have stainless steel type 316 cases with clearshatter resistant window.

Pressure gauges not subject to pulsation used for process air, instrument air, nitrogen, argonetc. do not require liquid fill. All other gauges shall have liquid (glycerine) fill.

Pressure gauges shall incorporate blowout protection devices on the rear of each gauge.

Case diameters shall be 100 mm for process indications and 25 mm for gauges monitoringinstrumentation, such as air filter/regulators and positioners.

Scaling shall be in kilopascals (kPa). Dial scales shall be marked in black on a whitebackground with a red zone mark to indicate the approaching of the upper pressure scale.

Diaphragm seals shall be used where necessary to protect pressure elements against corrosiveor plugging process conditions.

9.5.3 Pressure Switches

Pressure switch measuring element may be Bourdon tube, bellows, piston or diaphragm typedepending upon the service and pressure.

Pressure switches shall incorporate over-pressure protection to prevent pressurization of thecase in the event of failure of the measuring device.

Electrical switches shall have a contact rating of 24VDC, 2A minimum with SPDT contacts.

The operating point for pressure switches shall be field adjustable, but adjustment shall not bepossible without the use of tools.

9.5.4 Pressure Transmitters

Pressure transmitters shall use materials that are suitable for the process applications.

Pressure transmitters shall be constructed using corrosion-resistant materials throughout. Inthe case of single-ended pressure transmitters (i.e., those for gauge pressure service), thisrequirement includes the low-side instrument flange (that which is not connected to the processand is vented to atmosphere). For some brands of pressure transmitter, this may mean that alltransmitters must be purchased as differential-pressure models, since gauge pressuretransmitters may o

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