Maprom GS – Water-Lubricated Stern Tube Seal

Solution prior to pollution

We developed the Maprom GS seal to meet the demand for an efficient, reliable and environmentally sound water-lubricated propeller shaft seal. This unique water-lubricated seal works in an axial direction for shaftdia from 85mm up to 1050mm. No wear on the propeller shaft and easiest to install and operate; no need to dock the vessel because of standard incorporated service seal. Available for both inboard and outboard sealing purposes.

Sealing element

For both the GS Inboard Seal and the GS Outboard Seal the patented sealing elements are identical in design. They are produced by highly innovative injection moulding techniques guaranteeing 0,1 mm tolerances. The elements made of state of the art NBR or HNBR rubber are characterized by a superb durability. The compounds are developed and tested to reach lowest friction and thus longest lifetimes. The special profile of the sealing element incorporates more than one function:

  • Dirt repellent sealing element
  • Pressure repellent sealing element
  • Mechanical thrust shoulder
  • Bearing lubricant passages
  • Over pressure/venting and self lubricating

The sealing element can be bonded around the shaft in-situ without shaft removal. For that purpose the inboard GS Seal is supplied with an integrated inflatable sealing section so that maintenance can be carried out at sea, without the need for dry-docking. The cover (counter running surface) has an integrated second lifetime after re-machining thus reducing (on board) spares. The Maprom GS seals (split or unsplit) are the shortest seals in the market, enabling lower “edge loading” of stern tube bearings leading to lower total cost of ownership.

Maprom gs seal

"We believe in quality first. Maprom GS Seals often grant ship-owners 50.000 - 70.000 workinghours without service interval."

Intensive testing

Many years of intensive testing in our in-house R&D facility and proven track records on commercial and military vessels proved the Maprom GS Seal to be very reliable. Approved and accepted by all major classification societies. Also available Maprom GS Polar Seal, especially designed for Arctic conditions and elected by design bureaus to be superior compared to other water-lubricated seals operating in harsh environments. The Maprom GS seals are assessed by the Royal Dutch Navy to be shockproof.

Contact us

Looking for more information on our products or the best solution to your challenge? Meet us and discover how we meet or exceed your requirements in accordance with - and ahead of - all applicable quality, safety and environmental standards.

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Owners of a wide array of different vessels choose the high quality solutions Maprom Engineering provides: