Breakthrough System And Pipe Bending Technology For LSAW Steel Pipe
The breakthrough system lsaw steel pipe, improving concentration and repeated construction is a major cause of overcapacity. For example, in the seamless steel pipe industry, as of the end of 2012, China had about 144 sets of hot rolling mills with world-class levels, and its production capacity accounted for 62% of the total production capacity of seamless steel pipes. Among them, there are 30 sets of rolling mills with a capacity of 12.59 million tons; 59 sets of precision rolling mills with a capacity of 8.93 million tons; and 45 sets of three-roll mills with a capacity of 6.46 million tons.
In the welded pipe industry, there are 34 sets of straight seam submerged arc welded pipe units, 400 sets of spiral submerged arc welded pipe units and 2000 sets of high frequency straight seam welded pipe sets. The overall number of sets is large and scattered. In recent years, many new steel pipe units have intensified the contradiction of overcapacity, resulting in the imbalance of the structure and product structure of the steel pipe industry, the disorderly competition in the market, and the low efficiency of enterprises.
The straight seam submerged arc welded pipe is produced by using a single steel plate as a raw material, and is combined with other welding processes by JCO or UO molding, submerged arc welding or submerged arc welding. Commonly available are X70, X80, X120 and so on. The straight seam submerged arc welded pipe has a diameter ranging from 406 to 1422 mm and a wall thickness of 8-44.5 mm. In the aspect of welding edge processing, it adopts the milling machine processing method; in terms of molding, in addition to the conventional JCO and UO technology, some manufacturers adopt more advanced progressive forming (PFP) technology and roll bending forming (RBE) technology; In terms of argon gas protection or CO2 gas protection, the automatic pre-welding machine and special multi-wire (4 wire and 5 wire) internal and external submerged arc welding equipment, and the use of square wave power supply and power wave power supply device.
The whole pipe manager adopts mechanical expansion; for inspection, it is necessary to carry out on-line flaw detection on the plate, and after the steel pipe is welded, automatic ray + automatic ultrasonic flaw detection + hydraulic pressure test is carried out, and after the diameter is expanded, secondary online or offline ray + ultrasonic flaw detection is performed. Due to the limitation of the width of the coil and the production equipment, the straight seam welded pipe which is stably produced in China is an erw steel pipe with a diameter of 580 mm or less, and a straight seam submerged arc welded pipe with a larger specification.
The elbow is bent by a set of bending dies. No matter which kind of machinery and equipment, most of them use elbows, which are mainly used for oil transportation, gas transmission, infusion, etc., which are more important in the aircraft and its engine. status. The elbow can bend various profile sections, and almost all sections of aluminum, steel, stainless steel, copper and other metal profiles, pipes (spiral pipe, straight seam steel pipe, seamless pipe) can be bent.
The bent pipe has good bending quality, and the materials such as spraying, electroplating, polishing, drawing, etc. can be directly bent without damaging the surface of the material. The material of the variable diameter elbow: cast iron, stainless steel, alloy steel, malleable cast iron, carbon steel, non-ferrous metal and plastic. Connection to pipes: direct welding (the most common method) flange welding, hot melt bonding, threaded coupling, socket coupling, etc.According to the production process is divided into: welding elbows, stamping elbows, casting elbows, etc.
An elbow is a type of connecting pipe commonly used in pipe installation for the connection of a pipe bend. Other names: 90 degree bend, right angle bend, used for two pipes with the same or different nominal diameters to make the pipeline turn at a certain angle.