TWI standards activities

TWI plays a key role in the development of many standards which are important to the Oil, Gas and Chemicals Industries and is represented on the following committees:

BSI	WEE/2	Testing of welds
	WEE/17	Metal arc welding
	WEE/21	Pipework welding
	WEE/21/7	Field welding of pipelines
	WEE/28	Inert gas welding
	WEE/36	Approval testing of procedures
	WEE/37	Acceptance levels for welds
	WEE/39	Welding consumables
	WEE/40	Health and safety in welding
	WEE/41	Friction welding
	WEE/45	Welding of stainless steels
	WEE/46	NDT of welds
	ISE/12	Structural steel
	ISE/12/WG1	Offshore steels
	ISE/73	Steels for pressure purposes
	ISE/NFE/4	Testing of metals
	ISE/NFE/8	Corrosion of metals and alloys
	PVE/1	Pressure vessels
	PVE/15	Storage tanks
	PSE/17/2	Transmission pipeline for oil and gas
	PRI/80	Welding of thermoplastics
CEN	TC121	Welding (several working groups and subcommittees)
	TC54	Pressure vessels
	TC249/SC5	Welding of thermoplastic materials
ISO TC44		Testing of welds and welding quality
ISO TC67/SC2/WG8		Welding of pipelines
ISO TC67/SC7/WG3		Offshore tubular structures
EFC Oil & Gas and Refinery Working Parties
NACE	STG32	Oil & Gas Production - Metallurgy
	STG34	Petroleum Refining and Gas Processing
	TG299	Materials for use in H ₂ S containing environments in oil and gas production

Some of the most significant standards are as follows:

Fitness-for-purpose

TWI has held the chairmanship of the British Standards Institution committee (WEE/37) responsible for the new fitness-for-service guide BS7910 (replacing BS PD6493) since the committee came into being in the 1970s. BS7910 is the world's most widely used document for making structural integrity assessments and TWI has had a key role in its development. TWI made a significant contribution to the Materials Properties Council (MPC) joint industry project on fitness-for-service assessments which was subsequently incorporated into the new API RP579.

Fatigue

Most fatigue design rules throughout the world draw heavily on TWI work. In particular, the unified rules in BS 7608, those contained in offshore design guidance and those in the British pressure vessel code BS PD 5500.

Fracture toughness testing

The widely adopted CTOD test was developed principally by TWI who have contributed to the standardisation of the technique through the British Standards Institution, ASTM, CEN and ISO. TWI has also contributed to the standardisation of K _Ic and J testing methods.

Pipeline welding

TWI holds the chairmanship of the British Standards committee responsible for BS 4515 (WEE/21/7), probably the most widely recognised standard for pipeline welding apart from API 1104. This committee has recently developed a standard for the welding of duplex stainless steel pipelines. TWI also contributes to CEN and ISO work in this area.

Pressure vessels

TWI has contributed to both the British and new European pressure vessel Standards BS PD 5500 and prEN 13445 with regards to fatigue (as mentioned above), fracture toughness requirements, NDT flaw assessment and welding procedures.

Storage tanks

Rules for tanks for the storage of liquefied gases (BS 7777 and PD 7777) have drawn on crack arrest studies and engineering critical assessments carried out by TWI.

Materials selection for sour service

TWI staff as NACE Members provide input to NACE Technical Committees such as MR 0175, TM 0177 etc. related to the specific influence of welding upon sour service performance of C-Mn, low alloy steels and CRAs. Similarly, TWI is closely involved in the European Federation of Corrosion Standardisation activities in this area and parallel input via BSI Committees.

Welding steels without hydrogen cracking

BS EN 1001: Parts 1 and 2 which specify the welding procedures required to avoid hydrogen cracking is largely based on BS5135, itself developed from work carried out by TWI.

Full range of TWI standard activities

TWI services to the Oil & Gas industries