Gold plated metal seals for Oil & Gas couplings
Our customer designs and manufactures hydraulic distribution products and systems used to control subsea production systems for the offshore energy industry globally.
The application
This seal application was for a range of dual resistant hydraulic couplings, which were designed to be suitable for make and break under full system pressure. There were three different sizes in the same design of coupling.
The customer had been using a back-to-back elastomer O-ring arrangement, but wanted to develop a superior sealing solution in order to achieve a greater number of connect/disconnects per coupling (therefore improving the lifespan).
The application itself was high pressure at 15,000 psi. The temperature range wasn’t particularly demanding compared to other Oil & Gas applications, but because the couplings were for subsea equipment, there could be contact with well fluids and control fluids. As result the seals required NACE approval.
Our sealing solution
Our engineers recommended a metal seal for this application because of pressure and compatibility requirements with the various hydraulic fluids. The action of mating/de-mating the coupling meant this seal had to perform under a slightly dynamic movement.
The seal base alloy was NACE MR0175 heat treated to obtain the standard desired properties for oil and gas specific application service; (when a material that does not comply with the NACE MR0175 heat treatment requirement is exposed to H2S, catastrophic failure can take place). Gold plating of the seal was recommended due to its malleability and suitability for slightly dynamic operation.
Our metal seal solution was extensively cycle tested and the customer confirmed that the new concept metal seal solution performed under the required conditions with no leakage.
Customer Satisfaction
This sealing arrangement extended the life of the couplings by achieving 100 connect/disconnect cycles before the seals needed changing. This was substantially higher than the original sealing solution and gold plated metal seals are now supplied in production quantities.