Boreable plain bearing material
View Patent ↗A bearing, plastic bearing material, and a method for the production thereof are described. The bearing comprises a continuous consolidated bearing material layer impregnated into a porous layer, which is in turn mounted on a backing material.
1. A method of manufacture comprising:
providing a particulate mixture of polytetrafluoroethylene and an inorganic filler material;
forcing said mixture through a ram extruder to form an extruded, shape-retaining, unsintered tape or strip;
impregnating said extruded unsintered tape into a porous layer disposed upon a backing material;
sintering the impregnated unsintered tape at a temperature above the melting point of the polytetrafluoroethylene to form a continuous consolidated bearing material layer.
2. The method of claim 1 , wherein the additive particles are microscopically and macroscopically homogeneously distributed within the polytetrafluoroethylene matrix.
3. The method of claim 1 , wherein said backing material is a metal strip.
4. The method of claim 2 , wherein the porous layer comprises bronze particles sintered to the metal backing.
5. The method of claim 1 , wherein the additive material comprises an inorganic particulate filler.
6. The method of claim 5 , wherein the extruded unsintered tape comprises 10 to 30% by volume of inorganic filler material.
7. The method of claim 1 , wherein the extruded unsintered tape further comprises a polymeric material.
8. The method of claim 1 , wherein the extruded unsintered tape comprises polyphenylene sulphide.
9. The method of claim 8 , wherein the extruded unsintered tape comprises 30 to 70% by volume of polyphenylene sulphide.
10. The method of claim 1 , wherein the extruded unsintered tape layer is impregnated at a temperature below the melting point of polytetrafluoroethylene.
11. A method of manufacture comprising:
providing an extruded unsintered tape or strip comprising a polytetrafluoroethylene matrix and discrete particles of an additive material;
drying the unsintered tape at a temperature sufficient to remove a lubricant liquid from the unsintered tape before impregnating the unsintered tape into a porous layer;
impregnating said extruded unsintered tape into a porous layer disposed upon a backing material;
sintering the impregnated unsintered tape at a temperature above the melting point of the polytetrafluoroethylene to form a continuous consolidated bearing material layer.
12. The method of claim 1 , wherein the steps are a continuous process.
13. The method of claim 1 , wherein a portion of the bearing material layer is above the surface of the porous layer.