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 flaws in 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 | |
| ISO TC164/SC4 | Fracture toughness testing | |
| EFC Oil & Gas and Refinery Working Parties | ||
| NACE | STG32 | Oil & Gas Production - Metallurgy |
| STG34 | Petroleum Refining and Gas Processing | |
| TG299 | Materials for use in H2S 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 is also active on the committees that develop and maintain API 579-1 /ASME FFS-1 and R6.
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 and continue to contribute to the standardisation of the technique through the British Standards Institution, ASTM, CEN and ISO. TWI has also contributed to the standardisation of KIc and J testing methods. TWI has also contributed to the development of SENT testing (see DNV F107 and DNV F108) which is now widely used to evaluate fracture toughness of pipeline girth welds.
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
Contact us at oilandgas@twi.co.uk