Glass smooth kneading agent in the production of seamless steel tubes in the use of heat

Selection of traditional steel kneading produce graphite (flake graphite and oil, such as tar or grease mixed into the paint) as a lubricant. However, the disadvantage of graphite lubricant are: ① large thermal conductivity, thermal insulation is poor, tool and die temperature, wear fast, kneading long goods difficult. ② simple cause merchandise by carbon, stainless steel simple when kneading intergranular corrosion occurs, it is necessary to remove the kneading after the carburized layer, the results of increased metal consumption. ③ often cause environmental pollution.

Comparison of glass and graphite lubricant, its strengths are: ① glass thermal conductivity, to avoid excessive cooling billet appearance together can also play the role of maintenance workers die. ② with excellent smooth function, the choice of a large and progressive than kneading kneading speed kneading machine can then be expanded scale production of goods. ③ glass Glazes good chemical stability, does not result in arrangements shortcomings. ④ can easily change the ratio of the glass lubricant to obtain a different physical features (such as softening point, viscosity, etc.) to different materials used to knead the product requirements. ⑤ When the use of glass as a lubricant can be maintained clean. I fear, glass smooth agent strengths obvious. Many foreign research results indicate, kneading steel use glass Glazes work best.

Kneading the need for a smooth tube parts are: kneading molding, kneading drum and the mandrel three parts.
(1) kneading mode Smooth: Smooth mold pressed into the glass frit used to pad the way, that is, before kneading the glass mat is placed between the mold and the billet. To ensure the continuation of glass mat can soften the appearance of conflict, the demand of glass mat shape and mold Kong imports cone and match the shape of the blank ends. Glass mat tube diameter typically smaller in diameter than the kneading 3 ~ 5mm. Glass mat is less than or equal to the diameter of the hole diameter of the die hole. The thickness of the glass mat is usually taken blank length of 4% to 8%.

(2) kneading the smooth tube and the mandrel: kneading a smooth tube and the mandrel should be used in low softening point glass frit coated small particle size within the bore of the billet and the outer appearance. In addition, it is possible to wrap wrapped with a glass cloth and the appearance of the blank of the glass cloth of the way around the mandrel.

(3) appearance of the glass film tube removed: as conching glass lubricant used, kneading the exterior appearance of the residual steel having a thickness of 20 ~ 50μm glass film, the nature of the hard and brittle, detrimental to future processing and use, it is necessary to eradicate. Eradication measures have mechanical and chemical methods. Mechanical methods are blasting, water-cooled and tensile straightening and other methods. Elimination of the use of chemical glass film, since the appearance of the pipe lubricant residue on the glass has a high chemical stability, elimination of which needs an alkali solution or acid solution used. Inadequacies of pickling of various steel materials is that the erosion of large, the appearance may happen pickling steel, especially for larger carbon steel pipe erosion, and thus the utilization was limited. Currently selected pH joint eradication method.