Mobil Stern Tube Lubricant

Approved by

• William Denny and Brothers

Standards & approvals

Specifications

Brand

Mobil (ExxonMobil)

Category

Marine lubricants

Manufacturer code

201540301020

Availability

On request

Manufacturer's description

Mobil Stern Tube Lubricant is a high performance, high viscosity lubricant developed especially for the lubrication of Cedervall-type stern tube bearings used in ships and for certain bearings of ships' fin stabilizers. It is formulated from relatively high viscosity index base oils combined with emulsifiers, structure modifiers, surface active agents and corrosion preventives, and it emulsifies readily with seawater to form a stable, adhesive water-in-oil emulsion that provides effective, water-wash-resistant rust protection even under severe operating conditions. It is recommended for Cedervall-type stern tube bearings — a bronze or white metal bearing with an oil-tight inboard seal and a metallic outboard seal that is not fully oil-tight, requiring a lubricant that readily emulsifies with water — as well as for fin tilting bearings and the crux trunnion bearings of Denny-Brown-AEG ship stabilizers, holding builder approvals from Brown Brothers and Company, William Denny and Brothers, AEG and Deutsche Weft. Key benefits include selected viscometrics for effective lubrication of critical stabilizer and stern tube components, good emulsification that maintains lubrication in the presence of seawater, excellent rust and corrosion protection of bearing surfaces, multi-use capability that reduces the number of lubricants needed on board, and good viscosity retention that supports effective leakage control and reduced oil consumption — demonstrated in ship trials to give significantly lower consumption than prior formulations.

Applications

• Recommended for the lubrication of Cedervall-type stern-tube bearings on ships, where a high-viscosity, readily-emulsifying lubricant is recommended by the manufacturer.
• Also recommended for the lubrication of fin tilting bearings, as well as the crux trunnion bearings of Denny-Brown-AEG ship stabilizers, and is approved by the manufacturer for these applications.

Performance & benefits

• A single, carefully formulated lubricant can serve all three sets of bearings in stabilizers and stern tubes, since their requirements are sufficiently similar.
• Correct viscosity allows the lubricant to flow properly under gravity head without excessive consumption, while minimizing wear under heavy bearing loads.
• Protects bearings and other components from corrosion, and emulsifies with any seawater that passes the seals to maintain lubricating characteristics and minimize corrosion.
• In two extended ship trials, gave significantly reduced consumption compared to the previous formulation, at least as low as the best competitive product, with entirely satisfactory lubrication throughout.
• Selected viscometrics give effective lubrication of critical stabilizer and stern-tube components.
• Good emulsification properties emulsify readily to maintain lubrication in the presence of seawater.
• Excellent rust and corrosion properties protect critical bearing surfaces exposed to seawater.
• Multi-use capability reduces the number of lubricants required on board.
• Good viscosity retention in severe applications gives effective leakage control and reduced oil consumption.

Fits

• Ships & vessels