DE1103498B - Lubricants for the production of bare metal pipes from ferrous materials, in particular steel, by non-cutting cold forming of pipe blanks or pre-drawn pipes - Google Patents

Description

Lubricant for the production of bare metal pipes made of ferrous materials, in particular steel, through non-cutting cold forming of tube blanks or pre-drawn ones Tubes It is known to facilitate the non-cutting cold deformation of iron and steel to apply a phosphate layer on the workpiece and with the help of a Draw lubricant. The surface of the drawn workpiece is then of a absorbed phosphate layer in which lubricant residues are embedded. In those cases where a bare surface is required, an additional one is required Subsequent cleaning required, by pickling, if necessary also by an annealing process is achieved.

There is already a process in the manufacture of bare spring wires known, in which pickling takes place before the last train, whereby one through the last Train smoothed metallic surface is obtained. In the manufacture of bare It is still possible to use spring wires without a separate pickling step before the last one Train to come to a bare surface if at least for that last move a weakly acidic, water-soluble wire drawing grease is used.

The transfer of such a procedure as it is for spring wires is known, on the pipe drawing for the production of bare metal pipes is not possible. At best, a pipe afflicted with drawing errors is obtained, provided that .Pipe does not tear itself off when pulling.

Means for pre-treating metals for cold working are already available described, the 1 to 3% of a suitable acid of phosphorus, 5 to 30%, preferably saturated fatty acids with at least 12 carbon atoms or their glpcerides, 20 to 300 / a an organic solvent and at least 50% hydrocarbon oils with boiling points from 120 to 275 ° C. These funds are used to dry up at higher levels Temperature to apply a phosphate layer impregnated with lubricant. at However, as with cold working, these agents are applied to others Workpieces covered with a phosphate layer do not have a bare metal surface on the drawn workpiece, but rather a drawn-in one with lubricant residue Phosphate layer.

Similar results are obtained using the German method Patent specification 863 281, in which for the pretreatment of phosphatable workpieces for non-cutting shaping, the workpieces are treated in a phosphate solution, which works at room temperature or only slightly elevated temperature and the emulsifiable one Fats or oils are added.

There are also known lubricants for cold forming, in addition to a fat, an emulsifier and water contain phosphoric acid and zinc phosphate. These funds should be composed so that they can be processed on one Apply a phosphate coating when deforming the next workpiece. In such a So the free phosphoric acid must be matched to the zinc phosphate content be that a layer formation is possible.

Rust removal pastes have also already been proposed, consisting of a saponifiable oil or a fatty acid that can be converted into a soap as a thickening agent, emulsified in aqueous phosphoric acid. Here come the individual components, especially in amounts of 20 to 60% of a 1000% phosphoric acid, 5 to 35% Thickener and up to 5% stabilizer and / or surfactants, Rest water, for use.

It has now been found that a bare metal surface can be found in the steel pipe can get on the drawn tube when looking at the manufacture of these tubes by non-cutting cold forming of tube blanks or drawn tubes as lubricants one Mixture used, the 3 to 30 weight percent fat component, preferably animal Fat, optionally with the addition of vegetable, mineral or synthetic Fats, such as chlorinated paraffin, a per se known emulsifier for the fat in common Quantities, for example in quantities of 10 percent by weight, based on the fat component, 1 to 8 percent by weight, preferably 1.5 to 3 percent by weight, P205 in the form of Contains free phosphoric acid, the remainder being water. The mixture can still be acid-stable Contains thickeners, wetting agents, rust-preventing inhibitors and economy stains. Animal fat is preferably used as the fat component. Vegetable fats alone are less suitable, but can optionally be used as an additive to animal Fat can be used. Mineral and synthetic fats are preferred at most used in small quantities. As emulsifiers are the known ones for fat emulsification suitable usable. The emulsifier base and the amount of emulsifier depends according to the fat used and its amount.

The phosphoric acid content of the mixture is primarily determined according to the surface properties of the tube blank or the tubes that have already been pulled forward. If these are blank, a lower concentration of phosphoric acid in the mixture is sufficient than with pipe bobbins covered with rust or a phosphate layer or pulled forward Pipes. The purpose of the phosphoric acid content is to remove the rust or phosphate layer peel off without forming a new phosphate layer. This must be done when dimensioning the P205 content in the mixture must be taken into account. Therefore, higher P., 0 .. contents are required if the surface has to be stained bright. To be on the safe side, the Adjust the phosphoric acid content so that there is still free phosphoric acid during the drawing is present, since this is the easiest way to avoid a phosphate coating forms from the lubricant.

The phosphoric acid content of the mixture to be used as a lubricant must also be set according to how long the tube blank or the drawn-out tube will last is in contact with the lubricant before the pipe pull is carried out. Passes away longer time before the pipe is drawn, the P205 content must then be higher than with a short @ 'dwell time of the lubricant on the pipe before the train, so that the phosphoric acid does not come into contact with the metal surface during this dwell time reacts completely and forms a phosphate layer.

The mixture to be used as a lubricant can be used, for example, to produce shiny metallic surfaces when drawing annealed and pickled pipes. However, it is possible to draw the first puffs with the help of phosphate layers and only use the mixture to be used as a lubricant according to the invention in the last or the last puffs in order to keep the pipe surface metallically bright. The mixture is usually in the form of a A dilute aqueous emulsion is used, into which the tubes are dipped to apply the lubricant. However, it is also possible to apply the mixture in a paste-like consistency by brushing, etc. The mixture to be used as lubricant is preferably used in the form of a low-viscosity emulsion At room temperature, however, to remove heavy rust or thicker, indented phosphate layers, a temperature increase can be advantageous. example 1 A Mixture can be used from the following composition settlement 6 percent by weight beef fat, 4 percent by weight of raw wool fat, 1 percent by weight emulsifier (oleyl alcohol with 5 to 8 moles of ethylenoxy d), 1 to 2 percent by weight P205, 0.01 percent by weight economy stain (organic waste derivative of thiourea). Rest water. Example 2 Can be used as a lubricant for rusted pipe blanks a mixture of the following composition is used will: 6 percent by weight beef fat, 4 percent by weight of raw wool fat, 1 percent by weight emulsifier (oleyl and stearyl amine with 7 to 10 moles of ethylene oxide), 5 percent by weight P2 05, Rest water. Example 3 The following mixture can be used as a lubricant for degreasing pre-drawn pipes with a drawn-in phosphate layer: 10 percent by weight beef fat, 5 percent by weight rapeseed oil, 1.5 percent by weight emulsifier (fatty alcohol mixture with 2 to 7 moles of ethylene oxide), 2 to 3 percent by weight P205, remainder water.

A chlorinated paraffin can also be used instead of rapeseed oil. Example 4 The following mixture can be used as a lubricant with a more viscous consistency be: 15 percent by weight beef fat, 10 percent by weight raw wool fat, 2.5 percent by weight Emulsifier (fatty alcohol mixture with 2 to 7 moles of ethylene oxide), 1 percent by weight wetting agent, 4 to 5 percent by weight P205, the remainder water. The agent is to be used as a drawing paste, for example, in addition to one with a low-viscosity lubricant already provided tube to reinforce the effect on the outer surface.

Claims (2)

PATENT CLAIMS: 1. Use of a mixture of 3 to 30 percent by weight Fat component, preferably animal fat, optionally with the addition of vegetable, mineral or synthetic fats, an emulsifier for the fat, for example in amounts of 10 percent by weight, based on the fat component, 1 to 8 percent by weight, preferably 1.5 to 3 percent by weight, P205 in the form of free phosphoric acid, the remainder water, as Lubricant for the production of bare metal pipes made of ferrous materials, in particular steel, through non-cutting cold forming of tube blanks or pre-drawn ones Pipes. 2. Use of a mixture according to claim 1 with a further content of known thickeners, anti-corrosion agents, wetting agents and / or economy stains. References considered: U.S. Patent No. 2,739,915; Swiss Patent No. 302 553; Machu: Die Phosphatierung (1950), 23, p. 106, 117; Vogel, Handbuch der Metallbeizerei (1951), Vol. II, pp. 158, 443; K a d mer: Lubricants and machine lubrication (1941), pp. 249, 251.