Live Loaded Sealing Solution for Plunger Pumps

FTL Technology were commissioned to provide a more effective seal arrangement for a Triplex plunger pump. This plunger pump would be used as part of an underground gas storage project, required to run unmanned for a period of between four and six months.

The current sealing set up on the ram was experiencing significant leakage issues on test. The customer had no confidence in the sealing set up being able to perform unmanned for the lengthy duration of the application. The current sealing arrangement comprised of three standard braid and two fluorocarbon packings - including lantern rings for a lubrication and flush system. The set up was spring loaded from the non-pressure end.

Application Data

Speed 0.639 m/s
Pressure 220 bar
Stroke 180mm
Media Oily water
Temperature Range -10 to 100 degrees Centigrade
Ram 22% Duplex with HVOF Chrome Carbide



The customer wished to keep the lubrication and flush system, so the FTL Technology solution incorporated this element. However, the size of the lantern rings was reduced to afford the customer immediate cost savings on their previous seal arrangement.

Our solution was to live load the assembly from the pressure side, giving a constant sealing force. The packing material offered was a PTFE/Graphite compound, enabling smooth running and low friction coefficients. The packing material also had wear-resistant aramid edges, guarding against packing extrusion and protecting against the abrasive and chemically aggressive media surrounding the application.

This new seal arrangement was then coated heavily with a universally stable lubricant, ensuring superior lubrication particularly during the run-in phase. In addition, there were two bearing supports, including a static O-ring on the o/d to prevent a leak path behind the seal assembly. Our engineers also installed a bearing strip on the I/D.

On the end of the assembly, our team placed a bearing material anti-extrusion ring, and a seal on the glad ring to seal the flush - at approximately 3bar.



The pump was installed and ran unmanned for a total of seven months. As a result of the live loaded packing solution, no leakages were detected when the pump was retrieved, and the site has now been decommissioned successfully.

The customer has gone on to use FTL Technology for subsequent troublesome applications, including a live loaded system in a ram pump working in aggressive media (including barite, sand and sea water). In addition to more reliable service, the FTL packing solution delivered monthly cost savings of over €20k over the previous sealing system.

A live loaded packing solution improves sealing performance over conventional packings and chevron seals, with the addition of self lubricating capabilities and a significant reduction in low pressure leakage. The solution developed by FTL Technology in this case allows for more controlled wear loss, and together with full sealing design and technical back up at every stage of the consultation process, the customer experienced a high level of service which solved their leakage problem through high quality products and innovative engineering.

How can we help?
For more information on plunger pump seals and plunger pump packing, give us a call on 0113 252 1061 or get in touch with an FTL engineer today. Alternatively, use our Online Chat service to see how we can help.

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