Solid anti-friction devices – materials therefor – lubricant or se – Lubricants or separants for moving solid surfaces and... – Inorganic compound
Patent
1995-08-25
1998-09-01
McAvoy, Ellen M.
Solid anti-friction devices, materials therefor, lubricant or se
Lubricants or separants for moving solid surfaces and...
Inorganic compound
508165, 508178, 508180, 72 40, 72 41, 72 42, C10M12500, B21C 900
Patent
active
058011293
DESCRIPTION:
BRIEF SUMMARY
The present invention pertains to a process for applying a surface lubricant carrier layer to a material to be subsequently formed in a cold forming process, particularly to a wire material to be formed in a drawing process, where a solid lubricant can be subsequently applied to the lubricant carrier layer.
The invention further pertains to a special device for conducting this process, as well as to a novel material for application in the process of the invention, that is, for forming the lubricant carrier layer.
In cold forming processes, such as wire drawing but also tube drawing, deep-drawing and cold rolling, the application of a separating lubricant between material to be processed (the workpiece) and the respective tool is conventionally known (cf. Lueger, Lexicon of Technology, vol. 8, pp. 545-547, for instance). For this purpose, the raw material, usually preshaped by hot forming, particularly rolling, is first descaled, that is, an oxide layer formed on the material (especially an oxide layer formed in hot rolling, but rust as well) is removed in order to obtain a bare metal surface (cf. Lueger, vol. 5, p. 183). For wire, a multiple bending process is generally applied for descaling, with the wire being led around multiple deflection rolls, which disadvantageously leads to an undefined deformation (elongation) which was actually supposed to occur in a defined manner in the subsequent drawing processes. For a complete removal of oxide without residue, a pickling process has also been necessary thus far. For this pickling, the material, in a state unrolled into rings (so-called coils) in the case of wire, is dipped into an acid bath (lowering the pH to roughly 1) and subsequently watered (up to a pH value of roughly 6 to 7). This is typically followed by an additional neutralization in lime bath; a lubricant carrier layer is also formed by this so-called liming. Alternatively, this lubricant carrier layer can also be formed by phosphating (cf. Lueger, vol. 8, p. 546). The lubricant carrier layer (bottom filler) fills in the troughs of the rough material surface and thus serves to anchor a subsequently applied actual separating lubricant. In wire drawing, this is now generally a solid lubricant based on soap, particularly a metallic soap, such as lithium stearate (so-called "dry drawing," cf. Lueger, vol. 8, p. 124). In each drawing process, the wire is pulled through a drawing die of hard metal or diamond and is thereby reduced in diameter and elongated (plastic, essentially noncutting formation). In front of the drawing die is a container in which the solid lubricant is present, and the wire passes through this lubricant powder, continually entraining particles which then form a "lubricating film" in the drawing die.
In this known process, the high cost of pretreatment is a serious disadvantage. Particularly the "wet chemical process"--degreasing, pickling, passivation, wet coating (liming/phosphating)--leads to high operating costs as well as increasingly high disposal cost of the acids and neutralization and/or lime/phosphate sludges.
The present invention is therefore based on the objective of reducing the expense for the application of a lubricant carrier layer and preferably also for the required material pretreatment, but guaranteeing at the same time an at least uniformly good separating lubrication during the subsequent cold forming process. In particular, it is even intended to increase productivity by improved lubricating properties.
According to the invention, this is achieved by a novel dry coating process where, for the formation of the lubricant carrier layer, an equally novel dry carrier material is used, that is, a carrier material present in the "dry phase," not dissolved in water or some other solvent, is applied in the cold state (roughly, ordinary room temperature). This preferably powdered or granular dry carrier material is preferably applied mechanically by pressing or squeezing. The otherwise necessary wet chemical processes are therefore unnecessary.
The dry carrier materia
REFERENCES:
patent: 2703550 (1955-03-01), Bell
patent: 2736699 (1956-02-01), Carhart
patent: 3024193 (1962-03-01), Gaynor et al.
patent: 3047496 (1962-07-01), Rogers et al.
patent: 4404828 (1983-09-01), Blachford
patent: 4545227 (1985-10-01), Sudoh et al.
patent: 4553416 (1985-11-01), Sudoh et al.
patent: 4688411 (1987-08-01), Hagita et al.
patent: 4808245 (1989-02-01), Nishi et al.
patent: 5201206 (1993-04-01), Russo
patent: 5209092 (1993-05-01), Russo
Firma August Neuhoff
McAvoy Ellen M.
LandOfFree
Process and device for applying a lubricant carrier layer to a w does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process and device for applying a lubricant carrier layer to a w, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process and device for applying a lubricant carrier layer to a w will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-270151