Graphite Grease

The specimen should have parallel and fairly smooth surfaces, so that the friction between the metal plates and the specimen is eliminated. The latter is ensured by coating the specimen surfaces with graphite grease. The deformation in the specimen is measured at regular intervals, typically after 5,10, 20, 40, 80,120, 300, 600, 2400 and 3600 s. 

Although not a metal, graphite is an electrical conductor and is porous. With aluminium, it forms a battery that works quite well In a humid environment, the contact with graphite results in severe galvanic corrosion of aluminium. That is why it is recommended not to use natural or synthetic rubber joints loaded with graphite. Graphitic greases should also be... 

Various other soft materials without the layer—lattice stmcture are used as soHd lubricants (58), eg, basic white lead or lead carbonate [598-63-0] used in thread compounds, lime [1305-78-8] as a carrier in wire drawing, talc [14807-96-6] and bentonite [1302-78-9] as fillers for grease for cable pulling, and zinc oxide [1314-13-2] in high load capacity greases. Graphite fluoride is effective as a thin-film lubricant up to 400°C and is especially useful with a suitable binder such as polyimide varnish (59). Boric acid has been shown to have promise as a self-replenishing soHd composite (60). 

Graphite lubricants include the dry powder, admixtures with liquid lubricants or greases, volatile liquids compounded with film-forming substances to produce bonded dry films, synthetic resins and powder metal compositions containing graphite for bearings, and finely divided suspensions in liquids (colloidal graphite). 

E. S. Glauch, Graphite andits Use in Eubrication, National Lubricating Grease Institute, Chicago, HI., 1940. 

Molybdenum disulhde (M0S2), graphite, hexagonal boron nitride, and boric acid are examples of lamella materials commonly applied as solid lubricants. The self-lubricating nature of the materials results from the lamella crystalline structure that can shear easily to provide low friction. Some of these materials used to be added to oils and greases in powder forms to enhance their lubricity. Attention has been shifted in recent years to the production and use of nanosize particles of M0S2, WS2, and graphite to be dispersed in liquid lubricants, which yields substantial decreases in friction and wear. 

Polyvinylidene chloride, polyethylene, Kel-F PTFE graphite and silicone vacuum grease Copper or stainless steel C Most common metals for dry... 

Most common metals Most common metals Most common metals Most common metals. Polyvinylidene chloride, polyethylene, Kel-F PTFE graphite and silicone vacuum grease Copper or stainless steel Most common metals for dry gas. Stainless steel, titanium and nickel for moist gas... 

In tests of materials saturated with liq oxygen and subjected to 71-75 lb drop weight tests, the following were found acceptable (one de-tonation/40 impacts or none/20) fluorocarbon oils greases, graphite, halogenated biphenyl molybdenum disulfide lubricants, polyethylene... 

Ground joints should be greased with graphite or lubricants based on fluoropolymers valves should be moved daily to avoid seizing. 

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