Background
Rockatek recently completed a project for a key Oil & Gas client, in order to investigate the failure of a key component within one of the client’s core product lines. These failures were caused by elastomeric rotary seals on a sprung loaded rotating driveshaft, which were sealing between various medias. It was suspected that these premature in-service failures were a direct result of poor seal and housing designs.
Why Rockatek?
In order to complete successful design improvements, the failure mode must first be understood. The most effective way to do this is to replicate the failure mode in a laboratory environment. This base control failure test allows design improvements to be tested for comparison, prior to commercial implementation of the product line.
Rockatek’s 3-pronged approach to engineering consultancy enabled us to make significant improvements to the running life and reliability of the seal. We were able to replicate the failure mode in our rotatory seal test fixture (RST1), before completing various design changes.
The Rockatek team utilised computer analysis, as well as physical testing, in order to demonstrate the effects of the design changes first-hand and model the long-term improvements to the life and reliability of the seal. The client was then able to implement the design changes to the product line, resulting in a significant reduction of in-service seal failures.
Rockatek’s Capabilities
The Rockatek RST1 test rig has the capability to test elastomer, metal, ceramic and composite seals. We can apply elevated temperatures and pressures, and input variable rotation profiles within the drive and control system. The RST1 features three separate media chambers, allowing for cross seal media testing.
Results
Design changes were made to the seal profile, leading to a reduction in running torque and increased seal life. The housing arrangement design was also improved, producing a better working environment for the seal. This, in turn, will lead to less wear of the seal, dramatically reducing repair and maintenance / running costs.