US2383148A - Protective grease - Google Patents

Description

Patented Aug. 21, 1945 UNITED STATES PATENT OFFICE PROTECTIVE GREASE John D. Morgan, South Orange, and Russell E. Lowe, East Orange, N. J., assignors to Cities Service Oil Company, New York, N. Y., a corporation of Pennsylvania No Drawing. Application June 3, 1943,

Serial No. 489,444

'7 Claims. (Cl. 252-19) This invention relates to protective greases. More particularly the invention'relates to greases useful for protecting the parts of ocean-going vessels, such as submarines, from corrosion and at the same time providing a, grease which when submerged in the water will not separate or give off a material which will make an oil film or slick on the surface of the water.

A moist atmosphere, water mists and ocean water are very corrosive to metal parts. Many parts may be protected by covering with paints tecting mechanical parts from corrosion and at the same time acting as a lubricant when the parts are -moved.

Most of the lubricating greases now in iise have mineral oil lubricants in them and when these greases are submerged in water they separate so that the oil is released and comes to the surface of the water. This separation is injurious to the grease, butmore important, however, is the fact that the released oil (whether it is a mineral or vegetable oil) spreads a film or slick on the surface of the water and gives an indication of the location of the submerged submarine. Another object of the invention is to provide a greasewhich will not separate when submerged in the water and will not produce an oil slick.

The top or deck of the submarine has a large area or large number of mechanical parts mounted on it. This surface and machinery must be thoroughly coated with grease to pro-' tect it. When the submarine. with its coated deck and machinery is submerged the movement of the submarine and the movement of the water act to wash off and remove grease from the parts. Although this grease may be insoluble, if it comes to the surface and floats on the surface of the water it will act as a telltale even though it is'not as easy to see the grease as it is to see an oil film.

Accordingly another object of the invention is to provide a protective grease which is waterinsoluble and which is heavier than the water so that, if the grease becomes detached from the parts to which it'is applied, it will sink in the water and not give any indication on the surface of the water.

With these and other objects in view the invention consists in the protective grease here inafter described and particularly defined in the claims.

A grease which is water-insoluble and will not separate upon standing and which has a gravity heavier than water has the following formula:

Percent by weight Dark green petrolatum 68.64

Lithium stearate 8.80 Aluminum tristearate 1.76 Lead oleate (anhydrous) 0.40 Triblityl phosphite 0.40 Leaf lead 20.00

This same type of grease, but which has a gravity less than the gravity of water so that it will float, has the following composition:

Percent by weight Dark green petrolatum 85.00 Lithium stearate 11.00 Aluminum tristearate 2.20 Lead oleate (anhydrous) -s 0.50 Tributyl phosphite 0.50

The grease having the leaf lead has a high' gravity and will sink in water. Such a grease is very desirable for coating the mechanical 'parts H on the deck of a siibmarinc. On the other hand the grease described above which does not .have any leaf lead is a very desirable grease to place on; the deck of other seagoing vessels which are not submerged because this grease is very adhesive; -It..,has good lubricating qualities and is very efiective'in preventing corrosimi.

of the mechanical parts.

In order to make the greases described above,

the dark green petrolatum, which is a crude par-ts. The tributyl phosphite is added as an antioxidant to maintain a uniform composition of the grease so that the grease will not in itself act as a corrosive agent for the mechanical parts.

' The leaf lead which is in the form of small, thin scalelike pieces of lead, acts as a weighting agent to increase the gravity of the greaseu At the same time this finely divided lead gives extreme pressure characteristics to the grease and is a rust preventing agent. When the lead is-incorporated in the grease it does not separate and the lead will carry the grease to the bottom of a body of water and hold it there.

The greases have the following physical charaoteristics:

Grease containing leaf lead Percent by weight Dark green petrolatum 68164 Lithium stearate 8.80 Aluminum tristearate 1.76 Lead oleate (anhydrous) 0.40 Tributyl phosphite 0.40 Leaf lead 20.00

6. A protective coating grease comprising:

Percent by weight Dark green petrolatum 85.80 Lithium -stearate 1100 Aluminum tristearate -1 2.20 Anhydrous lead oleate 0.50 Tributyl phosphite 0.50

Melting point -F 400 Oil separation when standing under water 0 Water absorbed at 70 F per cent 20 Penetration mm-.. 162.5 Corrosion to copper 0 Specific gravity 1.048 Grease lighter than water Melting point ..F 400 I Oil separation when standing under water 0 Water absorbed at 70 F; per cent 20 Penetration mm 185.0 Corrosion to copper 0 Specific gravity 0.868

The dark green petrolatum is a semi-refined petrolatumhaving a' melting point of between 118 to 122 F. and a viscosity of 115 to 122 at 210 F.

The preferred form of the invention having been thus described what is claimed as new is:

1. A protective grease for coating andprotecting the mechanical equipment and other exposed metal parts on the outside of a submarine, comprising approximately 68% of crude petrolatum, approximately 8% of a lithium soap, approximatelyv 2% of aluminum soap, a small proportion of a lead soap, and approximately 20% of finely divided metallic lead.

\ 2. A protective grease for coating and protect; Y 8 the mechanical equipment and Qtherexposed metal parts on the outside of a submarine, comsoap, the remainder of the composition being essentially crude petrolatum.

4. A protective grease coating composition for coating exposed mechanical equipment and other metal parts, comprising approximately of crude petrolatum, approximately 11% of lithium stearate,- a, small proportion of lead oleate, and

approximately 2% of aluminum stearate.

5. A submarine grease comprising:

7. The method of protecting the external ,rneehanical equipment and other metal parts of a submarine where such parts are exposed to the action of sea water, which comprises applying to the metal parts to be exposed a protective coating comprising an intimately blended mixture of approximately 9% of lithium stearate, approximately 2% of aluminum stearate, a' small proportion of a lead soap, and approximately 20% of finely divided metallic lead, the remainder oi. the coating consisting essentially of crude petrolatum, said coating material having a specific gravity. greater than that of sea water whereby any of the coating removed from the submarine will sink and thereby avoid disclosing the location of the submarine.

JOHN D. MORGAN. RUSSELL E. LOWE.