Since the size of extubation die hole is smaller than the outer diameter of the capillary before drawing mill (removal of expansion outside), so as to make the front end of the capillary smoothly through the draft holes, so that the chuck jaws can pull trolley system folder live capillary head before pulling the capillary system will need to head to jump the queue (grind fine wool pipe ends to make it smaller than the outer diameter of the orifice size) to this end, the capillary should be heated in a certain length of slotted tube furnace end, generally 150 ~ 200mm, wall thickness depending on the heating temperature is between 750 ~ 900 ℃. Followed by 75 to 300 kg of air hammer jump the queue, grind fine fur head tube, usually in 22mm or less in diameter capillary available rotary hammer or roll forging machine grinding tip. Precision seamless tube defects and improve in order to clear before pulling the plastic system subjected to heat treatment and pickling, pickling remove residual acid but also for washing and drying. You can also use mechanical methods such as shot blasting, sandblasting and other alternative pickling to remove oxide scale. In order to reduce friction between the tool surface and precision seamless tube extubation time, in order to reduce tool wear and prolong its service life and reduced energy consumption, so as to ensure the quality of precision seamless tube, cold drawn capillary prior to smear lubricant.

Processing methods of lsaw steel pipe are following belows: 1. Steel casting: use forging hammer pressure reciprocating impact force or press the blank changed our desired shape and dimensions of a pressure processing approach. 2. Kneading: the steel metal placed in closed kneading Jane, applying pressure at one end of the metal is extruded from the die hole in the rules obtained had the same shape and dimensions of the products processing approach used for the production of non-ferrous metals sheet steel. 3. Rolling: the metal blank of steel through the gap (of various shapes) a pair of rotating rollers, due to roll crunch reduced cross-sectional data, the length of the added pressure processing approach. 4. Pullout steel: now rolled metal blank (type tube, products, etc.) through a die orifice dial into reduced cross-section length of the pull-added processing approach used mostly cold.

LSAW steel pipe heat treatment methods to treat First Skills mold plan planning should be reasonable, not too poor thickness, shape to be symmetrical with respect to large deformation mold deformation to master the rules, set aside allowance, portfolio planning on large, sophisticated messy mold can be used. For some messy precision molds can be used pre-heat treatment, aging heat treatment, quenching and nitriding to control the accuracy of the mold. When mold repair blisters, porosity, wear and other defects, selection of cold welding and other heat-affected small correction device to prevent the onset of deformation during repair. Precision messy mold to pre-heat treatment, machining process to eliminate the remaining episodes of stress. Precision messy mold, when conditions allow, try to use cryogenic vacuum heating process and hardening after quenching. Mold hardness in ensuring the premise, try to use pre-cooling, grading cooling or quenching temperature quenching techniques. Rational use of information. Precision messy mold material should choose a good micro-deformation of steel on steel carbide segregation serious mold should be a reasonable casting and heat treatment quenching and tempering, solution heat treatment on a large double refining and casting mold steel can not be carried out. Reasonable choice of heating temperature control heating rate, on messy precision molds can be heated slowly, preheating and other methods to reduce the mold uniform heating heat deformation.

Carburizing process for seamless steel tubes , steel pipe can be enhanced HRC hardness. Carburizing, is a method of metal surface treatment, carburizing mostly low-carbon steel or low alloy steel, the specific method is placed in a workpiece having active carburizing medium heated to 900--950 degrees Celsius single phase austenite region after holding sufficient time to make the carburizing medium decomposition of activated carbon atoms into the steel surface, thereby obtaining a high carbon surface, the center remains the original ingredients. After grinding the surface of the carburized layer was caused by softening phenomenon, known as tempering grinding process produces. This is because the fast grinding feed rate, wheel size and hardness or speed improper selection, or the grinding process cooling is not sufficient, it is easy to produce such defects. This is because the heat when grinding the surface softened sake. Grinding flashback defective parts wear is reduced. Hexagonal surface cracks, it is because the surfaces are too hard grinding wheel, and due to heat. Also with the lack of tempering heat treatment, residual stress too much about. After etching with an acid, any defective parts of the black, with no distinction between the defect at the open. This is generating heat tempering grinding. Making the horse so that body into Troostite organization's sake. In fact, after the grinding crack the naked eye can see.

304 stainless steel seamless pipe to prevent pitting corrosion method ① Avoid a halogen ion concentration. ② Ensure uniformity of oxygen or an oxidizing solution, and the solution was stirred to avoid the liquid is not flowing to small areas. ③ Increase the concentration of oxygen or to oxygen. ④ Increase the pH value. Compared with neutral or acid chlorides, pitting apparent alkaline chloride solution resulting in fewer, or no (hydroxide ions act as anti-corrosion agent). ⑤ Work at the lowest possible temperature. ⑥ Added passivating agent in corrosive media. Low concentrations of nitrate or chromate is valid (preferentially inhibiting ion adsorption on the metal surface, thereby preventing corrosion caused by chloride ion adsorption) in many media. ⑦ Cathodic corrosion protection. There is evidence that use of low-carbon steel, aluminum or zinc electrowinning corner stainless steel combination cathodic protection in seawater will not cause pitting. Molybdenum 2% -4% 304 stainless steel seamless pipe having good resistance to pitting corrosion. 304 stainless steel seamless pipe containing molybdenum can significantly reduce pitting or general corrosion, corrosive media such as sodium hydride, sea water, sulfurous acid, sulfuric acid, phosphoric acid and formic acid.