Failure Analysis of a Reciprocating Pump Valve

An offshore rig septuplex pump was experiencing chronic suction and discharge valve failures.  A more robust valve design implemented by the manufacturer did not solve the problem.  MSI engineers performed test stand and on-rig pulsation and vibration testing.  Structural and acoustic natural frequencies were determined by test, as well as the harmonic content of the pressure waves in the cylinders and manifolds. Tribological and metallurgical tests were also performed on the valves, guides, and seats.  It was determined that a firm deposit film which was forming on the valve guides was hanging-up the valves, causing them to close late and slamming shut.  Finite element analysis proved that the impact stress waves were strong enough to lead to fatigue of the valve plates.  The valve guide clearances and seat angle were changed slightly to discourage hang-up and high closure rate, solving the problem.






MSI In Action

Case Study

Driveshaft Failures in Mine Slurry Raw Water Service Pumps Cured

A major pump OEM called on MSI to help resolve multiple pump driveshaft failures for an ore mining company in East Africa.

Case Study

Simulating the Performance of a Spinal Implant

A manufacturer of an innovative spinal implant approached MSI for help in assessing the implant’s structural integrity.

Case Study

Dynamic Analysis of a Street Sweeper for the Manufacturer

To identify potential opportunities for early bearing failure, MSI performed experimental modal analysis (EMA) and operational deflection shape (ODS) tests on a prototype unit for the manufacturer.