As a result of hardware crevice corrosion issues associated with spiral wound gaskets with metallic inner rings on acidic service a novel solution utilizing the modified ptfe has been developed by Flexitallic to support their range of special products used in corrosive service. This novel solution utilizes the Sigma 588 material as the inner ring on the spiral wound gasket. The inner ring is there to fill the void so as not to allow the acid to get into the crevice and accelerate the corrosion process and also provides inner strength to the sealing element. The Sigma 588 is an unfilled structurally modified form of ptfe which has outstanding creep resistance over virgin ptfe. The propriety manufacturing process produces a sealing material free from any filler material which restricts the chemical resistance of other filled ptfe products. This 3rd generation modified ptfe from Flexitallic will reduce the amount of remachining of metallic pipeline flanges on toxic acid services on refineries, thus minimizing downtime and improving run rates as well as providing excellent sealing performance.

For further details please contact Flexitallic Application department.