Especially a sudden decrease in pressure is a major challenge for manufacturer and a great responsibility for engineers and operators in these applications. Sealing compounds used in the applications above often create a barrier against gaseous media if highly pressurized gas falls to a very low pressure level within a very short period of time. The result of this process is often a damage of the sealing. The elastomer material is either torn in various places or blistering on the surface. This process is called explosive decompression (ED). Only high-tech sealing compounds which were especially tested and designed with very good physical properties can be used in this sector.
For the high demands on elastomer seals against explosive decompression (AED/Anti Explosive Decompression) the independent manufacturer C. Otto Gehrckens – shortly named COG – developed seven different high-tech compounds which were intensively tested and are resistant against explosive decompression. Engineers and operators can choose between four FKM/FPM, two HNBR and one FFKM/FFPM compounds. All of these seven high-tech compounds fulfill the NORSOK Standard M-710 requirements for resistance against explosive decompression. Furthermore some of the compounds fulfil the important API 6A and 6D standard as well as the American NACE TM 0297 (Explosive decompression) and TM 0187 (sour gas) standard.
In applications of the natural gas production, such e. g. as pig traps, gate valves, ball cocks and other regulating valves the use of all seven AED compounds have been proven successfully in avoiding damages to the sealing caused by explosive decompression and consequently avoiding costly leakages.