Fisher ED, ET User Manual

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Fisher ED, ET User Manual

SIL Safety Manual

D103401X012

July 2010 ED, ET, EZ, HP, HPA Valves w/ 657/667 Actuator

SIL Safety Manual for Fisherr ED, ET, EZ,

HP, or HPA Valves with 657 / 667 Actuator

Purpose

This safety manual provides information necessary to design, install, verify and maintain a Safety Instrumented Function (SIF) utilizing the Fisher ED, ET, EZ, HP, or HPA valve with 657/667 actuator.

Introduction

This manual provides necessary requirements for meeting the IEC 61508 or IEC 61511 functional safety standards.

W1916-2/IL

W6848-1

 

 

W8120A-1

ED or ET Valve

EZ Valve

HP Valve with FIELDVUEt

 

 

DVC6000 Digital Valve Controller

 

Figure 1. Fisher Valve with 667 Actuator

 

www.Fisher.com

SIL Safety Manual

ED, ET, EZ, HP, HPA Valves w/ 657/667 Actuator

July 2010

Terms and Abbreviations

Safety: Freedom from unacceptable risk of harm.

Functional Safety: The ability of a system to carry out the actions necessary to achieve or to maintain a defined safe state for the equipment / machinery / plant / apparatus under control of the system.

Basic Safety: The equipment must be designed and manufactured such that it protects against risk of injury to persons by electrical shock and other hazards and against resulting fire and explosion. The protection must be effective under all conditions of the nominal operation and under single fault condition.

Safety Assessment: The investigation to arrive at a judgment - based on the facts - of the safety achieved by safety-related systems.

Fail-Safe State: State where valve actuator is de-energized and spring is extended.

Fail Safe: Failure that causes the valve to go to the defined fail-safe state without a demand from the process.

Fail Dangerous: Failure that does not respond to a demand from the process (i.e. being unable to go to the defined fail-safe state).

Fail Dangerous Undetected: Failure that is dangerous and that is not being diagnosed by automatic stroke testing.

Fail Dangerous Detected: Failure that is dangerous but is detected by automatic stroke testing.

Fail Annunciation Undetected: Failure that does not cause a false trip or prevent the safety function but does cause loss of an automatic diagnostic and is not detected by another diagnostic.

Fail Annunciation Detected: Failure that does not cause a false trip or prevent the safety function but does cause loss of an automatic diagnostic or false diagnostic indication.

Fail No Effect: Failure of a component that is part of the safety function but that has no effect on the safety function.

Low Demand Mode: Mode, where the frequency of demands for operation made on a safety-related system is no greater than twice the proof test frequency.

Acronyms

FMEDA: Failure Modes, Effects and Diagnostic

Analysis

HFT: Hardware Fault Tolerance

MOC: Management of Change. These are specific procedures often done when performing any work activities in compliance with government regulatory authorities.

PFDAVG: Average Probability of Failure on Demand

SFF: Safe Failure Fraction, the fraction of the overall failure rate of a device that results in either a safe fault or a diagnosed unsafe fault.

SIF: Safety Instrumented Function, a set of equipment intended to reduce the risk due to a specific hazard (a safety loop).

SIL: Safety Integrity Level, discrete level (one out of a possible four) for specifying the safety integrity requirements of the safety functions to be allocated to the E/E/PE safety-related systems where Safety Integrity Level 4 has the highest level of safety integrity and Safety Integrity Level 1 has the lowest.

SIS: Safety Instrumented System – Implementation of one or more Safety Instrumented Functions. A SIS is composed of any combination of sensor(s), logic solver(s), and final element(s).

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SIL Safety Manual

July 2010

ED, ET, EZ, HP, HPA Valves w/ 657/667 Actuator

Related Literature

Hardware Documents:

51.1:ED, Fisher ED, EAD, and EDR Sliding Stem Control Valves Bulletin: D100017X012

Fisher ED and EAD easy et Valves CL125 through CL600 Instruction Manual: D100390X012

51.1:ET, Fisher ET, EAT, and ETR Sliding Stem Control Valves Bulletin: D100022X012

Fisher ET and EAT easy et Valves CL125 through CL600 Instruction Manual: D100398X012

51.1:EZ, Fisher EZ Sliding Stem Control Valve

Bulletin: D100025X012

Fisher EZ easy et Control Valve Instruction Manual: D100401X012

51.2:HP, Fisher HP Series Control Valves Bulletin:

D101635X012

Fisher HP and HPA Control Valves Instruction

Manual: D101634X012

Guidelines/References:

DSafety Integrity Level Selection – Systematic Methods Including Layer of Protection Analysis, ISBN 1-55617-777-1, ISA

DControl System Safety Evaluation and Reliability, 2nd Edition, ISBN 1-55617-638-8, ISA

DSafety Instrumented Systems Verification, Practical Probabilistic Calculations, ISBN 1-55617-909-9, ISA

Reference Standards

Functional Safety

D IEC 61508: 2000 Functional safety of electrical/electronic/ programmable electronic safety-related systems

D ANSI/ISA 84.00.01-2004 (IEC 61511 Mod.) Functional Safety – Safety Instrumented Systems for the Process Industry Sector

Device Description

Fisher ED single-port valves (figure 1) have cage guiding, quick-change trim, and balanced push-down-to-close valve plug action. Valve configurations are as follows:

ED--Globe-style valve with metal-to-metal seating for all general applications over a wide variety of pressure drops and temperatures.

EAD--Angle version of ED, used to facilitate piping or in applications where a self-draining valve is required.

Fisher ET single-port valves (figure 1) have cage guiding, quick-change trim, and balanced push-down-to-close valve plug action. Valve configurations are as follows:

ET--Globe-style valve with metal-to-PTFE seating (standard for all except Cavitrol III cages) for stringent shutoff requirements, or metal-to-metal seating (standard for Cavitrol III cages, optional for all others) for higher temperatures.

EAT--Angle version of ET, used to facilitate piping or in applications which require a self-draining valve.

Fisher EZ valves (figure 1) are globe-style with integral end connections, post guiding, and quick-change trim. These valves are used in chemical or hydrocarbon processing applications or in applications that require control of nonlubricating, viscous, or other hard-to-handle fluids.

Fisher HP Series high-pressure globe and angle valves (figure 1) have metal seats, cage guiding, quick change trim, and push-down-to-close valve plug action. HPD, HPAD, HPT, and HPAT valves use balanced valve plugs. HPS and HPAS valves use an unbalanced valve plug. To provide a seal between the cage and a balanced valve plug, the HPD and HPAD valve plugs use piston rings; the HPT and HPAT valve plugs use a pressure-assisted seal ring. A Whisper Trim cage can be used with an HPD, HPAD, HPS, HPAS, HPT, or HPAT valve plug. A Cavitrol III cage can be used with an HPS, HPAS, HPT, or HPAT valve plug.

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