07 Fusible Plugs

Please note that this Content may change. These boiler training modules, incorporating sections of the HRA/ORR boiler code of practice, were prepared in 2013 as part of the HLF funded BESTT training plan project and will be progressively reviewed and updated by the BESTT Technical Committee. Fusible Plugs

Proposed Syllabus 2013

To be used in conjunction with:

HRA Guidance Note HGR-B9008- Is01

BESTT acknowledges the support of the HRA for allowing the use of the Guidance Notes

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HERITAGE RAILWAY ASSOCIATION

GUIDANCE NOTE

FUSIBLE PLUGS

Purpose This document describes good practice in relation to its subject to be carried out by Heritage Railways, Tramways and similar bodies to whom this document applies

Endorsement This document has been developed and fully endorsed by Her Majesty’s Railway Inspectorate, a directorate of the Office of Rail Regulation

Disclaimer The Heritage Railway Association has used its best endeavours to ensure that the content of this document is accurate, complete and suitable for its stated purpose. However it makes no warranties, express or implied, that compliance with the contents of this document shall be sufficient to ensure safe systems of work or operation. Accordingly the Heritage Railway Association will not be liable for its content or any subsequent use to which this document may be put.

Supply This document is published by the Heritage Railway Association Copies are available electronically via our website www.heritagerailways.com

Issue 01 May 2009 page 1 of 10 © Heritage Railway Association 2009 The Heritage Railway Association, Limited by Guarantee, is Registered in England and Wales No. 2226245 Registered office: 2 Littlestone Road, New Romney, Kent, TN28 8PL HGR-B9008-Is01______Fusible Plugs

Users of this Guidance Note should check the HRA website to ensure that they have the latest version.

Table of Contents 1. Introduction...... 3 2. Dimensional Notation ...... 3 3. Personal Protective Equipment ...... 3 4. Inspection ...... 3 5. General ...... 3 6. Competency...... 4 7. Maintenance plan ...... 4 8. Materials ...... 5 9. Tabulation of sizes...... 5 10. Thread form and tolerance ...... 6 11. Fusible plug thread length ...... 7 12. Methods of manufacture...... 7 13. Re-leading ...... 7 14. Methods of sealing plug in boiler...... 7 15. Removal and cleaning ...... 8 16. Inspections and faults of fusible plugs...... 8 17. Fitting plugs ...... 8 18. Testing in boiler ...... 9 19. References ...... 9 20. Appendix A: Method of leading new and used fusible plugs BR type...... 9

Issue 01 May 2009 page 2 of 10 © Heritage Railway Association 2009 The Heritage Railway Association, Limited by Guarantee, is Registered in England and Wales No. 2226245 Registered office: 2 Littlestone Road, New Romney, Kent, TN28 8PL ! HGR-B9008-Is01______Fusible Plugs

1. Introduction This Guidance Note is one of a series dealing with Locomotive Boilers that were produced by the 2006-9 meetings on “Steam Locomotive Boiler Codes of Practice”. Railway locomotive boilers are designed to create, store and distribute steam at high pressure. The working life of such a boiler can be considerably shortened if due care is not taken at all stages of inspection, repair, running maintenance and day-to-day running. In the past there have been a series of accidents and explosions due to work being undertaken without having due regard to the inherent risks involved. It is with that in mind that H.M.R.I. and H.R.A. set up the series of meetings of boiler practitioners to discuss the issues; distil good practice and codify it into this series of Guidance Notes. This guidance is written for the assistance of people competent to perform these tasks. In places the terminology used may be specific to such practitioners. This guidance will also be useful to those in a supervisory or more general role, however no work should be undertaken unless the people concerned are deemed competent to do so.

2. Dimensional Notation The original information frequently comes from documents that are in the imperial system only. Metric equivalents have been added where appropriate.

3. Personal Protective Equipment Before undertaking any works a risk assessment must be conducted. Protective equipment is to be supplied and used at work wherever there are risks to health and safety that cannot be adequately controlled in other ways. The equipment must be ! In accordance with the latest Personal Protective Equipment regulations. ! Properly assessed before use to ensure it is suitable. ! Maintained and stored properly ! Provided with instructions on how to use it safely ! Used correctly by those undertaking the work. 4. Inspection In the event of finding any fusible plug to be defective or suspect seek guidance from the boiler Competent Person or replace fusible plug with new item. The inspection should take account of the requirements in the ‘Written Scheme of Examination’ for the boiler under the Pressure Systems Regulations 2000.

5. General Most locomotive boilers designed to operate in the UK incorporate one or more fusible plugs fitted to the crown of the inner wrapper of the firebox. In the event of the water level within the boiler falling below the level of the crown the temperature of the wrapper plate work rises. A low melting point alloy within the fusible plug melts with this rise in temperature allowing steam from the boiler to escape into the firebox. This escape of steam if serious alerts the crew to the low water level. Fusible plugs take the form of a bronze or brass threaded plug which screws into a tapped hole in the wrapper, the thread may be either tapered or parallel depending upon design. If tapered the plug seals on the thread, if parallel it seals against a flanged face. The centre of the fusible plug is hollow with a hole drilled through on the axis of the thread. This hole is filled with either low melting point alloy or lead, alternatively it is filled with a combination of low melting point alloy or lead retaining a bronze or brass billet. Fusible plugs are usually screwed into the wrapper crown from the fire side of the plate and have a head, usually square, for driving the plug, see diagrams:

Issue 01 May 2009 page 3 of 10 © Heritage Railway Association 2009 The Heritage Railway Association, Limited by Guarantee, is Registered in England and Wales No. 2226245 Registered office: 2 Littlestone Road, New Romney, Kent, TN28 8PL ! Proposed BESTT Syllabus Assessment Plan ! ! ! ! ! 65$"( !"#$%&'( 5#9%"1":(5':( ./( /,0"#$%1"2( 322"22+"'$(4-%$"-%5( 6"7%1"-8(( )*+,"-( !*;"-1%2&-2( 2%<'5$*-"( Be able to correctly re- metal worn fusible Understand the plugs and produce 3 importance of using good plugs of differing LO1 the correct PPE and 3 types using correct Workshop 1 fume extraction when PPE and fume dealing with lead extraction. Know the based items! dangers of lead based materials! Knowledge of Be able to correctly LO1 materials used for a) 5 identify 5 differing Workshop 2 the plug and b) the firebox fusible plugs filling! Trainee must be able to Identification of grade a batch of 10 LO3 serviceable and 5 plugs into serviceable, Workshop 1 unserviceable fusible borderline and plugs unserviceable Know how a fusible Trainee to draw where plug functions, fusible plugs are sited potential danger for LO1 in the roof of a firebox 5 the crew, and why Classroom 3 and explain why. multiple plugs are Be able to explain why fitted to the firebox numbering is important crown Be able to fit 2 types of LO3 Be able to fit a fusible plugs safely and 5 Workshop 3 plug! satisfactorily under supervision Understand the Draw 3 common types different types of plugs of plugs; explain how & that the LO1 they are fitted and how 5 manufacture, Classroom 4 they function. What inspection and fitting does the term safety is a safety critical critical mean? process! ! HGR-B9008-Is01______Fusible Plugs

Sectional views of common types of plugs are shown below:

Parallel thread plug. Taper thread plug Proprietary plug, NABIC type

The NABIC type plug may be fitted from fireside or waterside depending upon design. IT CANNOT BE RELEADED. It must be fitted in accordance with the manufacturer’s instructions.

6. Competency The manufacture, inspection and fitting of fusible plugs are safety critical tasks. Only those trained, deemed competent and authorised should be responsible for the inspection of fusible plugs and plug holes, and refitting of fusible plugs. Records should be kept of the action taken at each washout and by whom.

7. Maintenance plan The boiler maintenance documentation should reference the identification and location within the firebox of each fusible plug, if the boiler has more than two fusible plugs preferably in pictorial form on a diagram (see example to the right). Each plug should be identifiable in accordance with the plan to ensure that it is always replaced in the correct position. The maintenance plan should record the thread size of each threaded hole in the wrapper crown to ensure the correct size plug is used.

Issue 01 May 2009 page 4 of 10 © Heritage Railway Association 2009 The Heritage Railway Association, Limited by Guarantee, is Registered in England and Wales No. 2226245 Registered office: 2 Littlestone Road, New Romney, Kent, TN28 8PL ! Proposed BESTT Syllabus Assessment Plan ! ! ! ! ! 65$"(5#9%"1":( 5':( !"#$%&'( ./( /,0"#$%1"2( 322"22+"'$(4-%$"-%5( 6"7%1"-8( !*;"-1%2&-2( )*+,"-( 2%<'5$*-"(

Be able to record on a maintenance plan Create a typical 2 LO1 7 the thread type, fusible plug Classroom 5 plug type and configuration record correctly number them ! HGR-B9008-Is01______Fusible Plugs

8. Materials Body The material for the body of the plug should be leaded gunmetal LG4 (or alternately brass CZ121) Core Pure lead 99.97%, melting point 327 degrees C Material records Certificates of chemical analysis and mechanical tests to the appropriate standards for the materials concerned should be held for the life of the plug.

9. Tabulation of sizes To accommodate the progressive wear of threads in boiler plates, particularly copper, fusible plugs are manufactured in a range of sizes. The diagrams to which the figures in the tables refer are given on the next page. Parallel threads The threads are usually coarse and the common sizes are detailed in Table 1 below. It is recommended that where possible the ‘BR late’ set of dimensions are followed for all new works. Plug type Drawing External thread Internal thread Square Dia Dia TPI length Dia oversize TPI AF Length Diagram ref> A - B C - - D E

BR SL/SW/88 late Post 1956 1 1/8 to 1 5/16 by 1/16 8 5/8 1/2 9/16 12 1 1/2 5/8

BR early SL/SW/88 1 1/8 to 1 5/16 by 1/16 8 5/8 5/8 11/16 11 1 1/2 5/8

GWR 101077 1 1/8 to 1 5/16 by 1/16 8 5/8 5/8 11/16 11 1 1/2 1/2

LMS 1 1/8 to 1 5/16 by 1/16 8

Taper threads The threads are usually fine and the common sizes are detailed in Table 2 below. Plug Internal type Drawing External thread thread Square Dia Taper TPI length Dia TPI AF Length Diagram ref> A - - B C - D E

LNER 822N 1 1/8 to 1 5/8 by 1/16 1 in 9 11 7/8 1/2 12 1 3/8 3/4

Southern 1 1/4 to 1 3/4 by 1/16 1 in 8 12 1 1/4 5/8 11 1 7/8 3/4

NABIC type Fig 5 fireside ! - " - 1 - 1# BSPT HEX head NABIC type Fig 8 waterside " - 1 - 1# - 1! 2 BSPT HEX head

Issue 01 May 2009 page 5 of 10 © Heritage Railway Association 2009 The Heritage Railway Association, Limited by Guarantee, is Registered in England and Wales No. 2226245 Registered office: 2 Littlestone Road, New Romney, Kent, TN28 8PL ! Proposed BESTT Syllabus Assessment Plan ! ! ! 65$"(5#9%"1":( 5':( !"#$%&'( ./( /,0"#$%1"2( 322"22+"'$(4-%$"-%5( 6"7%1"-8( !*;"-1%2&-2( )*+,"-( 2%<'5$*-"(

Know the What records would materials used, LO2 be kept referring to 8 leaded gunmetal Classroom 1 these materials and LG4 & pure lead where? melting at 327°C Interpretation of The selection of the LO1 the tabulation of correct type of plug 9 Classroom 6 fusible plug sizes for new work from and diagrams the tabulated data

Know the two Explain how each LO2 types of plug type achieves a 9 Classroom 2 used – taper or safe seal in the parallel seat crown ! HGR-B9008-Is01______Fusible Plugs

Parallel thread plug dimensions – Table 1 Taper thread plug dimensions – Table 2

Particular sizes of plug hole and corresponding plug should be recorded on the maintenance plan plug chart.

10. Thread form and tolerance Parallel threads will vary according to design but most are Whitworth form “close fit” as defined in BS 84. Taper threads will vary according to design but usually the threads are of Whitworth form. The TPI of the thread is always measured along the centreline of the fusible plug. There are two methods of cutting the threads on the plug, either a) square to the taper of the thread, this allows modern full form threading inserts to be used, or b) square to the centre line of the fusible plug, this requires especially ground full form chasers to cut the correct profile thread (see figure below).

Threads Normal to Taper Threads Normal to Centreline

Both methods are acceptable, however it is important that the two thread forms are not mixed up and that both boiler thread and fusible plug are to the same standard, only one type should be used on any single boiler. It is important that the boiler records and plug diagram (see item7 above) detail which form is in use on a boiler and that the fusible plugs and any spares are appropriately marked.

Issue 01 May 2009 page 6 of 10 © Heritage Railway Association 2009 The Heritage Railway Association, Limited by Guarantee, is Registered in England and Wales No. 2226245 Registered office: 2 Littlestone Road, New Romney, Kent, TN28 8PL ! Proposed BESTT Syllabus Assessment Plan ! ! ! 65$"(5#9%"1":( 5':( !"#$%&'( ./( /,0"#$%1"2( 322"22+"'$(4-%$"-%5( 6"7%1"-8( !*;"-1%2&-2( )*+,"-( 2%<'5$*-"(

Be aware of how the threads could Identify the different Workshop LO2 be cut on a taper thread types and 10 and 3 plug – parallel to explain how they Classroom axis or parallel to are produced. taper ! HGR-B9008-Is01______Fusible Plugs

11. Fusible plug thread length For parallel threads the thread of the fusible plug should be the same length as the thickness of the boiler plate and no thread should protrude through into the water space as this will become encrusted with scale, damaging the boiler plate on removal. In some works it was practice to fit a threaded ring into the crown when the maximum size of plug hole was reached, akin to a stay bush, fusible plugs for holes so modified require to be longer as the ring is thicker than the parent plate. For tapered threads there should be at least two threads clear through the boiler plate and at least two threads clearance between the boiler plate and the end of the thread at the head of the fusible plug.

12. Methods of manufacture Users are advised to purchase plugs from an experienced manufacturer. Various methods of manufacture have been adopted by different manufacturers and railway companies, all of which have advantages and drawbacks. A common method of leading plugs is detailed in Appendix A, whichever method is used the following should be taken into consideration:- 1. The lead filling of fusible plugs is toxic and appropriate precautions must be taken. 2. The use of tinning agents will affect the purity of the lead and produce an alloy; tinning agents should therefore be kept to a minimum. 3. Cleanliness is critical in producing a satisfactory product. 4. Only new pure lead should be used in manufacture as alloying elements rapidly reduce the melting point of the metal they are also subject to enhanced corrosion. 5. Used lead to be disposed of as hazardous waste. 6. Each fusible plug should be subjected to a hydraulic test. 7. Plugs should be stored individually to avoid damage to threads or lead inserts.

The finished plug should be marked with an indication of the size, manufacturer and date of manufacturing on a flat of the head of the plug.

13. Re-leading Fusible plugs which require the lead replacing because of corrosion should have the old lead melted out. Due to the difficulty in ensuring a suitably clean surface for the new lead to bond to the hole should be tapped out oversize, exposing fresh metal for tinning. This tapping out process should take place only once on each body. For details see Appendix A. Once re-leaded the plug should have a suitable identification stamp to indicate that re-leading has taken place. The use of a capital ‘R’ on the side of a flat of the head is recommended.

14. Methods of sealing plug in boiler Fusible plug threads should be sealed with a lubricating sealant such as Graphite grease; no hard setting sealant or jointing compound is to be used as this builds up over time in the thread forms and is difficult to remove from the fusible plug and hole. Suitable Graphite grease compounds are petroleum jelly based; compounds with linseed oil are hard setting and not suitable. The use of PTFE and PTFE tapes can cause toxic fumes at elevated temperatures (300+ degrees C) and their uses should be avoided in locations where elevated temperatures may be encountered.

Issue 01 May 2009 page 7 of 10 © Heritage Railway Association 2009 The Heritage Railway Association, Limited by Guarantee, is Registered in England and Wales No. 2226245 Registered office: 2 Littlestone Road, New Romney, Kent, TN28 8PL ! Proposed BESTT Syllabus Assessment Plan ! ! ! ! 65$"(5#9%"1":( !"#$%&'( 5':( ./( /,0"#$%1"2( 322"22+"'$(4-%$"-%5( 6"7%1"-8( )*+,"-( !*;"-1%2&-2( 2%<'5$*-"( Trainee must be able to Parallel threads recommend length need to be same LO2 of plugs and type 11 length as hole, taper Workshop 4 after researching 2 plugs need to finish separate fireboxes clear with different fusible plug types Fusible plugs must Know where to LO2 come from a 12 source Classroom 5 reputable replacement plugs manufacturer! Trainee to produce If plug can’t be one perfect fusible outsourced, plug paying LO2 understand the 13 attention to safety, Workshop 6 requirements to PPE, waste safely manufacture control, storage a replacement and cleanliness The trainee should be able to explain The use of PTFE LO1 why PTFE tape is 14 tape or PTFE based Classroom 7 not used at sealing compounds elevated temperatures ! HGR-B9008-Is01______Fusible Plugs

15. Removal and cleaning Period of removal Details of when plugs are to be removed for inspection should form part of the boiler records. It is recommended that fusible plugs be removed at every washout for inspection. Plug cleaning Fusible plugs are to be cleaned with fine hand wire brush to remove all deposits of Graphite grease and scale to leave a bright surface suitable for inspection. It is important to ensure that all boiler scale is removed from the surface of the lead on the water side and that all sooty build up is removed from the surface of the lead on the fire side. Hole cleaning. Holes are to be cleaned with a small wire brush, or tap if necessary; paraffin or similar solvent used with a tooth brush will leave a surface suitable for inspection. Storage of plugs Use of a partitioned tray to avoid plug threads becoming damaged by bruising.

16. Inspections and faults of fusible plugs The bodies of fusible plugs will suffer from corrosion on the fire side and chemical attack on the water side, as a result their life is limited and it is recommended that the boiler records detail the number of washouts before a plug is refilled and the total number of washouts before a fusible plug is scrapped. Typically the life of the lead filling is 2 or 3 washout periods and the total life of the fusible plug is 4 or 6 washout periods. Cracking at the undercut of the thread on parallel thread fusible plugs is a common mode of failure and requires special attention. Inspect for pulled threads especially on steel firebox plate work. Scrapped plugs are to be rendered unusable and destroyed. The lead filling will suffer from corrosion on the water side to an extent which varies with the quality of the boiler water. The lead / body interface will suffer from corrosion, particularly if tinning has been used in the manufacture of the plug. Unserviceable plugs that have already been re-leaded once are to be rendered unusable and destroyed. Holes in wrapper crowns will suffer from pulled threads and ripped threads. Copper is particularly prone to pulled threads. Any holes with signs of damage should be tapped to the next size up, removing all traces of damage or cross threading. When tapping threads use a sharp tap in conjunction with a cutting compound, ensure the tap is perpendicular to the plate and advance the tap by up to ! turn per cut and back off as required to free swarf. Avoid the end of the tap causing damage to internal components within the boiler, such as pipes and stays. When the maximum size hole has been reached and it requires renewal either the hole requires bushing or a new location is required, seek the advice of the Competent Person. When inspecting holes sufficient light must be available to illuminate all of the surfaces and if necessary a mirror to inspect parts of the thread not visible directly. For parallel thread plugs which seal on the face the wrapper plate requires a flat surface to form a seal against, inspect this face for damage. Fit of plug in hole. For parallel thread fusible plugs if there is any detectable movement of the plug in the crown thread then the fit is no longer close and the thread will need re-cutting to the next size. After re- cutting the thread the seat will need re-cutting to bring it square to the thread. For tapered threads there should be at least 2 threads clear through the boiler plate and at least 2 threads clearance between the boiler plate and the end of the thread at the head of the fusible plug.

17. Fitting plugs The boiler records should be consulted prior to re-fitting to ensure that the correct fusible plug is always fitted to the correct hole, this avoids fitting the wrong plug to a hole. Plug threads should be coated with Graphite grease, see thread sealant above, no hard setting lubricant or jointing compound is permitted. Firstly insert the plug into the hole and tighten by hand. To fully tighten use a purpose made socket which is a good fit on the head of the plug, push the socket hard up against the end of the head to avoid damaging the plug or twisting the head. When fitting plugs it is important that this is done as a single operation on each plug without distraction, the plug is either ‘out in the tray’ or ‘fitted tight’. Do not put all plugs in by hand and follow around with the socket. For most plugs a 12” T bar on the square socket will give an appropriate

Issue 01 May 2009 page 8 of 10 © Heritage Railway Association 2009 The Heritage Railway Association, Limited by Guarantee, is Registered in England and Wales No. 2226245 Registered office: 2 Littlestone Road, New Romney, Kent, TN28 8PL ! Proposed BESTT Syllabus Assessment Plan ! ! ! 65$"(5#9%"1":( !"#$%&'( 5':( ./( /,0"#$%1"2( 322"22+"'$(4-%$"-%5( 6"7%1"-8( )*+,"-( !*;"-1%2&-2( 2%<'5$*-"( Correctly identify the corrosion on a Inspection of fusible number of fusible LO3 plugs, 16 plugs and rate Classroom 1 Identifying types of them for corrosion replacement or further use Tapping of new fusible plug holes in Trainee to tap a LO3 16 crown and issues fusible plug hole in Workshop 2 arising from that sample material operation Observation of Fitting fusible plugs trainee fitting a LO3 17 Importance of a plug and tightening Workshop 3 single operation to the correct torque. ! HGR-B9008-Is01______Fusible Plugs torque when operated by hand (approximately 100Nm (75 ft lbs)). Do not over tighten by using an extension on the T bar handle.

18. Testing in boiler Plugs are to be inspected for leakage when the boiler is first steamed following the removal of any fusible plug. If leakage is detected no attempt is to be made to tighten the plug whilst the boiler is in steam. A further check on the tightness of the plug may be made when the boiler is cold, if necessary partly drain the boiler of water, remove the plug, inspect, clean and refit.

19. References SL/SW/88 BR Standard fusible plugs. GWR 101077 Standard stays and plugs for locomotive boilers. LMS “Red book” section B11. LNER “Fusible plugs in locomotive boilers” May 1940. HSE Free leaflet - indg305 Lead and you – A guide to working safely with lead HSE Free leaflet – indg304 Understanding Health Surveillance At Work-An Introduction for employers HSE L132 - Control of Lead at Work Regulations 2002. Approved code of practice and guidance

20. Appendix A: Method of leading new and used fusible plugs BR type

______end of main document ______

Issue 01 May 2009 page 9 of 10 © Heritage Railway Association 2009 The Heritage Railway Association, Limited by Guarantee, is Registered in England and Wales No. 2226245 Registered office: 2 Littlestone Road, New Romney, Kent, TN28 8PL ! Proposed BESTT Syllabus Assessment Plan ! ! ! 65$"(5#9%"1":( 5':( !"#$%&'( ./( /,0"#$%1"2( 322"22+"'$(4-%$"-%5( 6"7%1"-8( !*;"-1%2&-2( )*+,"-( 2%<'5$*-"(

Observe Trainee Testing of plug in inspecting a plug LO3 18 the boiler and and question on Workshop 4 rectification of a leak how to remedy the problem Trainee to list Leading of new LO3 procedures and 20 plugs and re-leading Workshop 5 carry out on one of used plugs plug HGR-B9008-Is01______Fusible Plugs

Appendix A Method of leading new and used fusible plugs BR type

Leading new plugs 1. Paint internal thread and countersink with a zinc chloride activated (Sn40 Pb60) solder paint. 2. Warm plug until tinned. 3. Warm up lead. 4. Place warm plug in mould. 5. Pour lead and let set. 6. When plug is cold enough remove and lightly hammer crown, drift lightly bottom of lead. 7. Remove excess lead from crown. 8. Wire brush and examine.

Re-leading previously used plugs N.B. Plugs may only be re-leaded once 1. Melt out lead in a ventilated area, allow to cool. 2. Wire brush. 3. Clean out threaded portion with a tap one size larger. 4. Clean out countersink with a suitably ground hand drill. 5. Examine general condition of square and external thread for distortion and deterioration of size. 6. Check undercut for any signs of cracking. 7. If items 5 and 6 are OK proceed as for new plugs.

______end of appendix ______

Issue 01 May 2009 page 10 of 10 © Heritage Railway Association 2009 The Heritage Railway Association, Limited by Guarantee, is Registered in England and Wales No. 2226245 Registered office: 2 Littlestone Road, New Romney, Kent, TN28 8PL ! Proposed BESTT Syllabus Assessment Plan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