Something About TAT Shell Valve MESC Group
What is Type acceptance test (TAT)?
It is not uncommon for certain applications that a new type of valve will have to be developed to meet the end user’s needs. Most end users have the highest technical demands on valves they are aiming to use in an assembly. Needless to say these ‘prototypes’ will undergo extensive testing to verify the reliability, safety, etc. TAT (Shell MESC SPE 77/300) is one of the internationally recognized certification to ensure the quality of the valves.
TAT is done as per ‘Shell’ specification 77-300 in which the valve is subjected to seat test, fugitive emission test, and torque test under pressure, during and after mechanical and thermal cycling. The qualification range is mentioned in spec 77/300B.
It is testing that is done on a product to confirm the design is good. It is a product performance test that is different from FAT (Factory Acceptance Test), which is done to verify the quality of the product coming out of the factory.
In short, TAT = DVT = design verification testing
and FAT = Verfication of production quality
What is Shell Valve?
SHELL, in the valve world, usually means ‘Shell Petroleum’， a world-renowned giant in the energy industry, ranking top 3 in the global petroleum and petrochemical industry. Shell's business covers 145 countries, and its business covers the sales of fuel and lubricants at gas stations, the exploration and production of oil on land and offshore, and the development and production of natural gas.
As an end-user of petroleum and petrochemical valves, the company has many special, demanding and detailed requirements for valve products, and has formed its unique set of complete and strict technical specifications system, which was recognized worldwide, and taken as standard for the valve manufacturing.
MESC and MESC Group 76/77/81/85
Group 76 Fitting & Flanges
Group 77 Valves & Accessories
Group 81 Fasteners & etc.
Group 85 Jointing (gaskets), Packing & Insulating materials
MESC Group 77 Valves & Accessories:
77/1XX: Design & Manufacture
77/2XX: Special Service
77/3XX: Test & Inspection
MESC: Material and Equipment Standards and Code
| Main Group | Sub Group | Sub-Sub Group | Item Number | Indicator |
| XX . XX . XX . | XXX. | X | ||
For example:
| Main | Sub | Sub-Sub | Item Number | Indicator | |
| 77. | Valves | ||||
| 00. | Ball Valve, Carbon Steel | ||||
| 72. | SPI6D, Soft Seated, Temp. Range: 0℃~150℃, FE Class: B | ||||
| 120. | CL600, DN450, RB, RF | ||||
| 1. | Centrally Code | ||||
