DRIVEN BY PERFECTION
Maprom Engineering has second to none experience when it comes to water lubricated propeller shaft systems. For several decades we have been a leading supplier of water lubricated bearing-, stern tube- and sealing- systems to vessels all over the world.
Maprom Scope of Supply ranges from water lubricated propeller shaft turn key deliveries including engineering to delivery of standard or customised parts (e.g. bearings, seals or lub. System components)
A water lubricated propellershaft system operates in either open- or closed- sterntube layout. Unlike others, Maprom systems function well with fresh water, seawater and/or brackish water. Additives like a small amount of Glycol against freezing may be used but are not necessary and thus environmentally sound systems are guaranteed. Maprom water lubricated sterntube systems are widely and successfully used in both inland and sea going vessels, ranging in shaft standard diameter from 80 up to 650 mm and beyond.
|1. In an A-bracket, outboard water lubricates the bearing system, either by natural flow or by force feeding. Especially for abrasive inland river conditions we recommend the use of hardcoated NCB shaft sleeves (58-62 HRc) shrink fitted over the propellershaft, as counter running surface for the bearings to guarantee optimal life times.|
||2. In open systems the same bearings and shaftliners are recommended. In addition Maprom forward sterntube seals are mounted including a simple, but reliable, lubrication system. For highly abrasive river conditions we recommend maintenance free and non-clogging Maprom MK Separators.|
3. Mounting both Maprom forward GS- and aft GS-seal on either end of the stern tube creates the by Maprom introduced closed water lubricated systems. These systems have been used on river applications since the beginning of the 70-ties. In closed systems our bearings and NCB liners have achieved operational lifetimes in access of 100.000 running hours.
This system obviously has more barriers against the ingress of contaminated water. The system, however, requires an on-board lubrication tank. In closed systems, the risk for shaft-corrosion is less. The use of constant and controlled quality freshwater for lubrication, with or without additives, enables the installation of simpler (bronze e.g.) shaft liners. Closed systems show lower wear rates and consequently longer life times of the bearing systems.