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Wells ABC Guide to

Temporary Pipework Practices to implement EP 2006-5393 Shell Global Standard for Temporary Pipework

I.E. Iyamu (SPDC EPG-PN-WS; B.A. Beltman (SIEP EPT-WN); G. Hampden-Smith (SUKEP EPE-T-WS)

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Wells ABC Guide to Temporary Pipework Practices to Implement EP 2006-5393 Shell Global Standard for Temporary Pipework by I. E. Iyamu (SPDC EPG-PN-WS); B. A. Beltman (SIEP EPT-WN); G. Hampden-Smith (SUKEP EPE-T-WS)

Sponsor: Reviewed by:

P. Sharpe (SIEP EPT-W)

Approved by:

I. Duncan (SUKEP EPE-T-WS) D. Stewart (SIEP EPT-WX)

Date of issue:

December 2007

Period of work:

November 2007

Revised: ECCN number:

February 2012 EAR 99

The information in this document is shared under the Research Agreement between SIRM and Shell Oil Company dated January 1, 1960, as amended unless indicated otherwise above. This document is classified as Restricted. Access is allowed to Shell personnel, designated Associate Companies and Contractors working on Shell projects who have signed a confidentiality agreement with a Shell Group Company. 'Shell Personnel' includes all staff with a personal contract with a Shell Group Company. Issuance of this document is restricted to staff employed by a Shell Group Company. Neither the whole nor any part of this document may be disclosed to Non-Shell Personnel without the prior written consent of the copyright owners. Copyright 2007 SIEP, Inc.

SHELL INTERNATIONAL EXPLORATION AND PRODUCTION INC., HOUSTON Further electronic copies can be obtained from the Global EP Library, Houston

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Summary This ABC Guide to Temporary Pipework is designed as a practical guide to create an awareness of the risks when using temporary pipework in the field. This guide covers: 

Flowline equipment



Pressures and types of fluids involved



Operational hazards



Pipework connections and interfaces



Hazard identification and mitigation



Operational guidelines

This guide shall be read and understood by all involved in temporary pipework operations. The guide shall be re-read prior to the commencement of each temporary pipework operation and also referred to during each step of that operation. If the correct procedure is unclear at any stage of the operation: Stop and Ask.

Figure 1 - Examples of temporary pipework

Keywords Temporary pipework, Hammer Union, Hub Connection, Hoses, Restraints.

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Revision History Revision 4 Section

Details

5.1.3

Replaced charts in the section and expanded on commercial options for restraining pipework.

5.1.4

Removed revision 3 content and replaced with selection and installation of Polyester Round Sling Restraints.

5.1.5

Removed revision 3 content and replaced with information on the WeirSPM FLSR system.

5.1.6

Removed revision 3 content and replaced with information on FMC TPR system

Appendix 3

Restraint Charts using ASME B 30.9 Polyester Roundslings

Revision 5 Section

Details

2.10

Added section. Direction of flow through Hammer Unions.

4.4

Amended some text to include the use of NPT and linepipe threads.

4.4.3

Added this section to specify the conditions for using NPT and line pipe threaded connections > 1/2”.

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Contents Summary

I

Keywords

I

Revision History

II

Revision 4

II

Revision 5

II

Introduction

1

1.1

What is Temporary Pipework

1

1.2

Pipework or Flowline Equipment

2

1.3

Equipment Boundaries

2

1

2

3

Hammer Unions and Operational Hazards

5

2.1

Origins of Hammer Unions

5

2.2

Female/Male Subs or Union Parts

5

2.3

Pressure

6

2.4

Stored Energy

8

2.5

Dynamic Loading

8

2.6

Vibration

8

2.7

Bending Forces

9

2.8

Shock Loading

10

2.9

Hazardous Fluids

10

2.10 Conventional Hammer Union Pipework Hook-up – Direction of Flow

10

Loss of Containment

10

3.1

Leaks - Erosion

11

3.2

H2S

12

3.3

Catastrophic Failure

12

3.4

Energy Release

13

3.5

Polymers – Elastomers and Thermoplastics - suitability

13

3.6

3.5.1 Elastomers 3.5.2 Thermoplastics Historic Incidents

16 17 18

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Pipework Connections and Interfaces

21

4.1

Hammer Union Mismatches

21

4.1.1 4.1.2 4.1.3 4.1.4 4.1.5

21 24 25 25

4.2

5

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Mismatching the Same-Size Hammer Unions Mismatching Pipe Pressure Ratings Mismatching Wing Nuts Mismatching Components Mismatching Non-Detachable and Detachable Components 4.1.6 Connecting a Hammer Union Male Sub from one manufacturer to the Female Sub from a different manufacturer Mismatching Swivel Joint Components

26

26 27

4.3

Mating Hub Connector Components from different manufacturers

27

4.4

Threaded Connections

28

4.5

4.4.1 Non-Pressure Sealing Thread (NPST) & Pressure Sealing Thread (PST) Line Pipe and NPT 4.4.2 Line pipe, NPT, NPTF 4.4.3 Pressure Sealing Threaded (PST) Connections greater than 1/2” Flexible Pipes - Hoses

4.6

4.5.1 Suitability of hoses connected in the high pressure 40 (> 285 psi) side of the process. 4.5.2 Handling, Storage and Maintainance of Flexible Pipe 41 Equipment Interfaces & Equipment Repair and Maintenance 42

Hazard Identification and Mitigation

5.1

29 32 38 40

43

Mitigation Methods

43

5.1.1 Checklists 5.1.2 No-Go areas 5.1.3 Restraints for Temporary Pipework using Polyester Roundslings 5.1.4 Installation Steps for Polyester Round Slings 5.1.5 WeirSPM FSR System 5.1.6 FMC Technologies TPR System

43 46

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Avoiding Injury

58

6.1

Hammering Unions

58

6.2

Positioning of Body

59

7

Completing the Connection Interface Diagram

60

8

Walking the Lines

63

8.1

63

9

Example walkthrough

Awareness of Safety Initiatives

65

9.1

65

Truncated 2 in. FIG 602 Female Sub

10 EP 2006-5393 Temporary Pipework Standard Compliance

10.1 Gap Analysis and Corrective Action Checklist

66

66

References

67

Appendix 1

Different Hammer Union Male and Female Sub mating arrangements. 68

Appendix 2

Piping Schedules

Appendix 3

Restraint Charts using ASME B 30.9 Polyester

70

Roundslings.

72

List of Figures Figure 1

Examples of temporary pipework

I

Figure 2

Temporary pipework / permanent pipework

1

Figure 3

Typical temporary pipework set-ups

2

Figure 4

Equipment interface boundaries, welltest and pumping examples

3

Figure 5

Some typical temporary pipework

3

Figure 6

Temporary pipework connections

4

Figure 7

Female sub and male sub of hammer type union

5

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Figure 8

3in. 1502 and 3 in. 206 connections

6

Figure 9

Relative Pressure Comparison

7

Figure 10 Vibration in Temporary Pipework

9

Figure 11 Bend is being straightened due to internal pressure

9

Figure 12 Direction of Flow in Conventional Hook-up

10

Figure 13 Erosion point in a short radius bend

11

Figure 14 Erosion of common equipment

12

Figure 15 Demonstration of energy involved in Catastrophic Failure 13 Figure 16 Example of Hammer Union Seals incorporating anti extrusion rings

16

Figure 17 Mismatch of hammer union end connections

22

Figure 18 Using the Go No-Go gauge

23

Figure 19 Mismatching of wing union components

24

Figure 20 Mismatch caused by misidentification - standard male sub 25 Figure 21 Mismatch caused by misidentification - detachable male sub

25

Figure 22 Misapplication of wing nuts

26

Figure 23 Another misapplication of wing nuts

26

Figure 25 Mating Hub Connectors

27

Figure 24 Dangers of mismatching swivel joint components

27

Figure 26 NPT in poor condition due to corrosion and with insufficient make-up

28

Figure 27 NPST vs. LPT

29

Figure 28 FMC NPST Hammer Union Subs with groove 0.38” from ends

30

Figure 29 FMC NPST Retrofitted-groove schematics

31

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Figure 30 Line pipe connections which parted under rapid pressure increase and violent transverse movement

32

Figure 31 NPT thread gauging

34

Figure 32 NPT thread gauging and engagement - high pressure (>6000 psi) fittings

35

Figure 33 Example of split female connections

36

Figure 34 Leakage path through NPT threads

36

Figure 35 Clock wise wrapping procedure

37

Figure 36 Minimum bending radius of flexible pipe

41

Figure 37 Hose installing concept for long spans

42

Figure 38 Dynamic loading and selection guide of EN 1492-2 round sling restraints for liquid pressurised piping

48

Figure 39 Dynamic loading and selection guide of EN 1492-2 round sling restraints for gas pressurised piping

49

Figure 40 Condition of lugs on hammer union wing nuts

58

Figure 41 Safety iron

58

Figure 42 Safety hammer

59

Figure 43 Gauge positioned directly above a pressurised pipe connection

59

Figure 44 Sand Filter and Dataheader showing NPT connections

59

Figure 45 CID toolbox guide

60

Figure 46 CID toolbox video tutorial

61

Figure 47 P & ID showing connections marked-up for walking the lines

62

Figure 48 Example things to consider during walking the lines

64

Figure 49 Truncated 2 in. Fig 602 Female Sub - new engineering design

65

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List of Tables Table 1 Elastomer Selection Guide

14

Table 2 Thermoplastic Selection Guide

17

Table 3 Historic Incidents

18

Table 4 Hammer Union Mismatches To Avoid

21

Table 5 Indicative Torques for High Pressure (> 6000 psi) NPT fittings

34

Table 6: Allowed threaded connection working pressures for different pipe sizes 38 Table 7 Normal pressure < 6000 psi NPT nominal sizes and thread engagement data.

39

Table 8 Example of Pre-Mobilisation Temporary Pipework Checklist 44 Table 9 Pre-Pressure Test Temporary Pipework Checklist

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1

Introduction

1.1

What is Temporary Pipework

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Temporary pipework consists of the conduits and equipment for directing fluids (liquids or gasses): 

From a pump to a Xmas Tree.



A high pressure point to a lower pressure point.



Fluids directed to outlets ending with plugs on which sensors are mounted. Permanent pipework

Temporary pipework

Pipework part of original design (e.g. production facilities)

To temporary pipework system

Figure 2 - Temporary pipework / permanent pipework

Temporary pipework is piping and flowline equipment that is mobilised to the wellsite for connecting or hooking up equipment for the following operations: 

General pumping operations (transfer of fluids, mud/brine mixing operations, (reverse) circulating well fluids, etc.



Pressure testing of downhole equipment (casing, packers, tubing, plugs, valves, accessories).



Cementing.



Well killing.



Well stimulation.



Nitrogen pumping.



Well clean-up (Flowbacks).



Well testing.



Under balanced drilling operations.



Managed pressure drilling operations.

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Temporary pipework can be both hard and flexible pipe.

Figure 3 - Typical temporary pipework set-ups

1.2

Pipework or Flowline equipment

The equipment involved can include: 

Pipework runs (straights), pup joints, elbows.

 

T-pieces. Laterals (Y-pieces).



Swivel joints.



Treating loops.



Crossovers.



High pressure hoses.



Flanges, blinds, plugs, tappings for sensors, sample points etc.

1.3

Equipment Boundaries

Pipework components contained within pumping or flowing packages: e.g. manifolds, pumping units, separator tanks are excluded where these are manufactured to a code or standard. The pipework connections or interfaces to the equipment are included.

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Interfaces included

Interfaces included

Equipment “D” e.g. Steam Heat Exchanger

Equipment “C” e.g. MSRV

Equipment excluded

Equipment excluded

Equipment “B” e.g. Choke Manifold

Interfaces included Equipment “A” e.g. Surface Test Tree

Interfaces included

Blender

Equipment excluded

Equipment excluded

Interfaces included

Pump Truck

Treatment Manifold

Xmas Tree

Interfaces included

Figure 4 - Equipment interface boundaries, welltest and pumping examples

Pipework

Treating loop

Swivel Joint

Tee

Typical Coflexip Line

Figure 5 - Some typical temporary pipework Wells

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The pipework connections referred to in the guide are known as: 

Hammer-type connections.



Hub-type connections.



Flange connections.



Pipe body to pipe body (welded) or pipe body to Sub. - gas welded - friction welded Thread Pipe body to Sub - NPST (no pressure seal on thread) - PST (pressure seal on thread) Hammer-type union

Hub-type connection

Flange connection Welded connection

Figure 6 - Temporary pipework connections

In summary, temporary pipework (chiksan, flowline equipment) comprises such fittings as straights or “pup joints,” T-pieces, elbows, crosses, crossovers, blinds, plugs, swivel joints and plug, loops, and check valves. Wells

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Hammer Unions and Operational Hazards

As previously described, temporary pipework operations involve the transport of fluids under pressure from one point to another. Due to the typical pressures and flow rates involved, temporary pipework systems contain a lot of stored energy which can cause vibration, bending forces, and shock loading on the system. The fluids being flowed can be hazardous or erosive, and can also “attack” the integrity or strength of the system. It is therefore vitally important that all equipment used in a temporary pipework operation set-up is: 

Mechanically sound and has been properly inspected prior to use.



Of suitable material, particularly where seals are concerned; this applies both to working pressure rating and to the fluid type being flowed (e.g. Sour Service).



Made up correctly at all connections and unions as per the recommendations of the operational design.



Secured with engineered restraints attached to strong anchor points in the system.

In order to better understand these requirements, we will now look at some of the physical aspects of temporary pipework.

2.1

Origins of Hammer Unions

Pipework connected by hammer unions is used in chemical process plants, the mining industry, on dredging vessels, and in the oil industry. It is an old design (early 1950s) created by the Well Equipment Company (WECO) which was acquired by FMC Technologies.

2.2

Female/Male Subs or Union Parts

The identification of the female and male parts of a hammer type union is show in the picture below.

Female Sub

Male Sub

Wing ut

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Figure 7 - Female sub and male sub of hammer type union

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The union parts are “called out” using a Nominal pipe size, a FIG “designation” and a code e.g.1502. For example: 3 in. FIG 1502 The “3 in.” is the nominal diameter and is close to the inside diameter. The meaning of “FIG” is probably an abbreviation of “figure” – meaning drawing, and 1502 is a code for the working pressure rating – “15” referring to 15,000 psi. The addition of H2S pipework has led to the designation becoming corrupted. 3 in. Fig 1502 H2S service pipework ordered from the major flowline equipment providers has a cold WP rating of 10,000 psi. The last two digits in the designation of hammer unions generally refers to the sealing arrangements. “02” refers to a square gasket seal; “06” refers to an o-ring seal.

1502 Square gasket seal

206 O-ring seal

Figure 8 - 3in. 1502 and 3 in. 206 connections

[See Appendix 1 showing different Hammer Union types]

2.3

Pressure

Pressure is the term for measuring the force per unit area, the units typically used for measuring pressure are pounds per square inch, which is abbreviated psi. A familiar example is the air pressure in a tyre, which is typically around 30 psi for a car. What this means is that a force of 30 pounds is exerted on each and every square inch of the inside of the tyre. There are a lot of square inches on the inside surface of a tyre, and because of this, the force exerted on that tyre is very large. Every square inch is pushed on with a force of 30 pounds. In temporary pipework operations, “low pressure” is often used for values of around 300 psi (that is 10 times that of a car tyre) and the operational pressure Wells

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may be above 10,000 psi, that is, 10,000 lbs exerted on every square inch of the inside of piping, unions, swivel joints, crossovers, etc., in the system. Units of Pressure Pounds per square inch (or pounds-force per square inch) is still the most widely used oilfield unit for pressure. Other common units are the SI (or metric) unit which is the Pascal (Pa), the Atmosphere (atm), and the Bar (bar). The Pascal is a very small unit, 1 Pa being only about 1/7000th p.s.i. 1 Atm and 1 Bar are approximately 15 p.s.i.

High

10,000 psi pressure High pressure

10,000 psi

~6000 psi (ASME B31.3)

Normal Operating Pressure

285 psi “Low Pressure”

30 psi

Car Tyre

Figure 9 - Relative Pressure Comparison

Thinking about the forces involved, it should be clear why it is vital to ensure there are no weak points in the system. Any improper use of equipment such as mismatching pressure ratings or using poorly conditioned equipment can have devastating consequences. Wells

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Stored Energy

Stored energy is the capacity of a volume of pressured fluid to do work if allowed to expand. An example of this work would be a volume of pressurised gas expanding and pushing a piston. The greater the stored energy of the fluid, the greater the force with which the piston would be pushed and the greater the amount of work that piston could perform. The danger associated with stored energy in temporary pipework is that the stored energy is typically very large, and any weak point in the system will allow this energy to discharge with potentially catastrophic results. Yield strength: - Pipework - Cannon comparison Yield Strength is the stress a material can withstand without permanent deformation. Typical minimum yield strengths for pipework range from 75,000 to 115,000 psi A liner comprising of steel tubing with 0.375 in. wall thickness and 85,000 psi yield strength is what is required to line the bore of 8-pounder cannons to make them safe for re-enactments of the American Civil War.

2.5

Dynamic Loading

When pipe fails the strain on any restraint when it snaps tight to restrain the pipe is called the dynamic loading by process engineers. The rule-of-thumb used to work out this dynamic loading is twice that due to the static force on the pipe arising from internal pressure.

2.6

Vibration

Vibration can be a significant risk to pipework integrity, leading to mechanical failure, fluid release, and potentially serious safety implications. Common areas of vibration in Temporary Pipework are: 

Long pipe runs.



Piping fixtures and instrumentation such as gauges.



Equipment such as valves, chokes, etc.



Pumps.

Common causes of vibration include: 

Excessive pulsation (from pumps for example).



Mechanical natural frequencies.



Inadequate supports and/or support structure.

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Common effects of vibration include: 

Loosening of bolts.



Compromising of mechanical joints (backing-off of wing nuts).



Movement or slackening of tie downs and restraints.

Figure 10 - Vibration in Temporary Pipework

2.7

Bending Forces

Temporary pipework is commonly subjected to bending forces due to fluid velocity and internal pressure of the pipe. Bending force occurs at junctions or bends in the pipework where it effectively tries to “straighten out the bend.” Internal pressure attempts to straighten out the corner bend and forces the pipe outwards straining the connections

Figure 11 - Bend is being straightened due to internal pressure

Such bending forces are then transferred along the pipework and result in additional strain on connections. Improperly made-up connections (e.g., worn or mismatched components, wrong pressure rating, etc.) not able to cope with this increased load can fail catastrophically. Wells

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Shock Loading

A significant change in the flowrate, or pressure, during an operation (such as the emergency closure of a valve) causes a sudden extra load or “jolt” on the system. The temporary increase of load on the system usually imposes increased pressure, vibration, and bending forces on the system. During this period of Shock Loading, any sub-standard part of the system (inferior pipe, worn connections, mismatched connections, wrong pressure rated equipment) can fail with potentially disastrous consequences.

2.9

Hazardous Fluids

While there are many physical factors (such as pressure, temperature, and flowrates) that must be considered when dealing with temporary pipework, chemical factors such as hazardous fluids must also be taken into account. Many fluids used in operations (such as brines or acids) are corrosive to temporary pipework and will cause a reduction in wall thickness. It is important that all pipework and connections used have been properly maintained, inspected, and certified before use. Standard Service components shall not be used on “Sour Service” wells (wells where Hydrogen Sulphide, H2S, is present), as this will cause stress corrosion cracking, and pitting in the metal as well as destroying any elastomer seals in unions, etc. These factors can lead to premature failure under pressure of components in the system.

2.10 Conventional Hammer Union Pipework Hook-up – Direction of Flow By convention, the flow enters the pipe work on the female sub side and circulates from the female sub to the male sub. All testing services equipment is manufactured to adhere to this convention and it should be followed whenever possible. However, there is no technical requirement for this convention and under certain circumstances, such as in a complex rig up or due to crossover availability, it may be required to rig up a line where the direction of flow is reversed. Any such line where the direction of flow is reversed must be clearly marked as to the true direction of flow.

Figure 12 - Direction of Flow in Conventional Hook-up Wells

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3

Loss of Containment

3.1

Leaks - Erosion

Erosion takes place in flow systems where turbulence occurs, typically in pipe bends (e.g., elbows), tube constrictions (e.g., chokes or valves), and other structures that alter flow direction such as laterals or tees. Specific erosion points within these components can vary depending on the fluid velocity and size of any suspended particles. With typically sized sand grains, the erosion point in a bend is usually past the mid-point of the bend, and it is for this reason that wall thickness is measured at the 80-90 degree point as well as at 45 degrees.

~80o

Erosion point

Figure 13 - Erosion point in a short radius bend

Erosion can lead to leakage and a rapid failure, and it is therefore important that the layout is designed, where possible, to minimise bends and constrictions and that such areas are inspected regularly. Examples where erosion can be accelerated are: 

Connections downstream of the choke.



Points where the flowline is re-directed.

Protection is afforded by using Target “T”s and log sweep bends. Intrusion into the flow path can cause vortices to be created and shed. The local fluid speed within the vortex can be much greater than the average fluid speed in the pipe. Local pipe erosion, in an area as small as ½ inch square, can arise where the vortex makes contact with the equipment or pipe wall. Since the pipe thickness can be otherwise within operational limits, workshop personnel should be vigilant when making visual inspections.

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Flow

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Flow Maximum erosion Maximum erosion

Plugged tee

Standard elbow (r/D=1.5)

Flow Maximum erosion

Predicted erosion rates for standard elbow, plugged tee and long-radius elbow. Areas shown in red and yellow have maximum erosion

Long-radius elbow (r/D=5.0)

Figure 14 - Erosion of common equipment

3.2

H 2S

When H2S is present, the system is known as Sour and Sour Service equipment shall be used. For working pressure above 6000 psi, Sour Service equipment has a significantly lower rated cold working pressure than the equivalent Standard Service equipment and it is therefore important to avoid mixing Standard and Sour Service equipment in the same operation.

3.3

Catastrophic Failure

When flow lines fail, whether it is due to excess pressure; faulty connections; worn components; damage to the piping connection; or other reasons, the results can be devastating and catastrophic to both equipment and personnel. The metal components that were previously being subjected to up to 15,000 p.s.i. of internal pressure are suddenly and instantly forced to relieve their stored energy. In such a failure there could be hundreds or even thousands of pounds of iron pipe flailing around. In that scenario, there is a high likelihood of severe personal injury or death. As we will cover later, restraint systems can help reduce this risk of damage or injury but they cannot eliminate it fully. Preventing the failure from occurring in the first place is the only truly safe method. Wells

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Energy Release

The following sequence of pictures were taken from a Service Company demonstration video showing the failure of a 15,000 p.s.i. unrestrained line. In this catastrophic failure the energy release occurs in a very short period of time - a fraction of a second in fact, and the damage and risk to personnel would have been severe.

Line ruptures

Test manikins 15,000 psi line

Pup joint flies off and lands 200 yards away Test manikins destroyed

Piece of loop flies outward

Figure 15 - Demonstration of energy involved in Catastrophic Failure

3.5

Polymers – Elastomers and Thermoplastics - suitability

“Polymer” is the name given to the class of chemical compounds that are moulded to make the elements of a sealing system. The “elastomers” comprise the deformable sealing element and the “thermoplastics” comprise the hard, nondeformable elements that limit the extrusion of the elastomers under pressure. In selecting the elastomers and thermoplastics, consideration must be given to the pressure, temperature, fluids and duration to which the polymers are exposed along with the mechanics of the leak path which the sealing arrangement “cutsoff”. The selection of suitable o-ring, seal and back-up ring polymers, as environmental conditions become more extreme, is challenging. It is difficult to be prescriptive on elastomer selection. Different grades or compounds of the same material type extend its range of use, but generally in one direction - to only one end of the temperature range: Elastomers compounded for very high temperature are not generally suitable for very low temperatures and vice versa.

Wells

20/02/2012

10:42

Pa

ABC Guide to Temporary Pipework-Rev5-Feb20-12:Wells ABC Guide to Temporary Pipework

Restricted

EP2007-3153 rev 5

- 14 -

Table 1 has been compiled by James Walker in consultation with Shell. Generic elastomer compounds are identified in this table. It is intended to guide Wells Supervisors and persons responsible for preparing equipment for Wells operations as to the conditions where they should seek advice (from the Seal manufacturer in the first instance) on the suitability of the seal etc. type and to where seal qualification may be appropriate. Table 1 - Elastomer Selection Guide Key 1 = excellent, 2 = good, 3 = poor, C = consult Chem-OLion®

Kalrez® 3018

PB 80

Elast-OLion® 985

Elast-OLion® 280LF

Elast-OLion® 280

Elast-OLion® 101

LR6316*

LR5853*

FR58/90*

FR25/90

FR10/80 & FR10/95

FFKM

Special

NBR

(perfluoroelastomer)

(nitrile)

HNBR

HNBR

(hydrogenated nitrile)

HNBR

(hydrogenated nitrile)

HNBR

(hydrogenated nitrile)

(hydrogenated nitrile)

FKM-GFLT

FKM-F

(fluorocarbon)

FKM-B

(fluorocarbon)

FKM-GLT

(fluorocarbon)

FKM-A

(fluorocarbon)

(fluorocarbon)

(Aflas®)

FEPM

(Aflas®)

FEPM

Material type

AF85/90

AF69/90

James Walker grade (Note: alternative materials are available)

Weak mineral

1

1

1

1

1

1

1

2

2

2

2

2

1

1

Strong mineral

1

1

1

1

1

1

1

3

3

3

3

3

1

1

Weak carboxylic

1

1

1

1

1

1

1

1

1

1

1

1

1

1

Strong carboxylic

2

2

3

3

3

3

3

3

3

3

3

3

1

1

Alcohols except methanol

1

1

1

1

1

1

1

1

1

1

1

1

1

1

Aliphatic hydrocarbons

1

1

1

1

1

1

1

1

1

1

1

1

1

1

Aromatic hydrocarbons

2

2

1

1

1

1

1

C

C

C

C

3

1

1

LD – Ca/Na chloride

1

1

1

1

1

1

1

1

1

1

1

1

1

1

HD – Na/Ca bromide

1

1

1

1

1

1

1

2

2

2

2

3

1

1

HD – Zn bromide

1

1

1

1

1

1

1

3

3

3

3

3

1

1

Alkaline – Na OH/KOH

1

1

3

3

3

3

2

1

1

1

1

2

1

2

Dilute

1

1

1

1

1

1

1

1

1

1

1

1

1

1

Concentrated

2

2

3

3

3

3

3

3

3

3

3

3

1

1

2

2

3

2

2

3

3

1

1

1

1

1

1

3

Amine based

1

1

3

3

3

2

2

1

1

1

1

3

1

1

Potassium carbonate

1

1

3

3

3

3

3

2

2

2

2

3

1

2

2

2

1

1

1

1

1

1

1

1

2

2

1

1