BPG 6903


Cover Seals are supplied as pre-formed rings and offer proven high performance, especially in heavy-duty valves or high-pressure feed water pre-heaters. The products remain elastic even with fluctuating temperatures and seating stress up to 200 MPa. Clearances of up to 0.3 mm can be sealed without difficulty and even larger gaps can be controlled by BPG graphite rings reinforced with stainless steel springs integrated into the corners or full metal caps.



The product is designed for use in heavyduty valve applications and high pressure feed water preheaters.



BPG Cover Seals are specially manufactured according to specification and application requirements. Media pressure (MPa) and dimension (ID, OD) are the key operating factors which determine the correct design. BPG 6903 features an inside angle with metal cap and one full stainless steel metal cap. More details on request.



BPG Cover Seals are available with a standard density of 1.6 g/cm³, with 99.85 % C-content in nuclear quality and 98 % industrial quality, in a wide range of variations e.g. rectangular, with inside or outside angle, with integrated extrusion protection in form of metal caps. Additional designs available on request.

Operation Parameters

Temperature–200°C … +550°C (almost all media and air)
–200°C … +700°C (steam)
pH Value0 … 14
Pressure100 MPa


Product Specifications

Media*Hot water and feed water, steam, heat transfer oils, hydrocarbons and many other media.
Certificates / ApprovalsBAM approval for gaseous oxygen (45MPa up to 60°C; 22MPa up to 200°C)
*Exceptions: strongly oxidising media


  • High level of chemical resistance and thermal stability
  • Excellent sealing ability and good elasticity
  • Not subject to cold flow, shrinkage or ageing
  • BPG 6903 fulfils the purity requirements for seals in nuclear power station valves (content of soluble chlorides < 20 ppm)
  • BPG Cover Seals are very adaptable, reliable and maintain their elasticity which offers potential savings in costs and time


Cover Seal


Data Sheet BPG 6903