| dc.description.abstract | Multiphase Pumps have demonstrated their capability to operate successfully in pumping the product extremes, means 100%liquid up to 100% gas, as well as solids This duty is difficult for a pump and thus even more difficult for its mechanical seals, whichare a critical component of any pumpMechanical seals are readily available for liquid or gas applications However, in a multiphase pump the mechanical seals are exposedto transient conditions, means crude oil with a (natural) gas content of up to 100% Consequently, special mechanical seals had to bedeveloped to handle multiphase mixtures, like crude oil and formation/produced water, gas like condensate up to methane, but alsosolids like sand or all kind of debris or cracked hydrocarbon productsThe biggest challenge for a mechanical seal manufacturer is to design extremely stiff sliding seal faces with the ability to maintainacceptable liquid lubrication to avoiding contact and wear of the mechanical seal faces Another challenge is the proper selection ofthe secondary sealing element materials, which are prone to extrusion, excessive wear and explosive decompression associated withsealing gases under high pressuresIn this tutorial, we would like to share an overview about the most used multiphase pump technologies, like twin-screw pumps,progressive cavity pumps and helico-axial pumps We would like to describe the challenges for its mechanical seals, as some pumptypes use only one mechanical seal, some pump types require up to four mechanical sealsWe would like to focus on a comprehensive overview about the different concepts sealing multiphase with single seals or with dualseal arrangements, handling density variations, viscosity variations, erosion and corrosion effects at high or extremely lowtemperatures in Onshore, Offshore and even Subsea applications We will also describe specific seal face materials, like DiamondFace Technology, a new face material which offers specific benefits in these multiphase applications | |
