Industrial production of large straight seam welded pipe by forming different ways can be divided into the following categories.
1, UOE process
The so-called "UOE" process is the first U-shaped steel plate, and then by O forming and expanding, it with three hydroformed to open the tube, and then sent to the welding process. The steel plate is firstly longitudinally edged and chamfered on both sides, and positioned and soldered on the four fillets, and then sent to the crimping machine to progressively press the two sides into a curved shape along the longitudinal direction at first, and then to the hydraulic press flat steel plate pressed into U-shaped, and then transported to O forming hydraulic press, pressed by the upper and lower semicircular die into an open tube. The pressing process is carried out in a precise hydraulic control, giving the open tube a consistent tolerance of tolerance. UOE unit maximum production capacity, product quality, is the world's production of high-precision pipeline steel pipe lsaw pipe unit.
2, RBE (three roll bending plate) process
Similarly, the edge of the board is also trimmed and chamfered on both sides in the longitudinal direction first, then the flat steel plate is repeatedly rolled into a circular open pipe body on a three-roll plate bending machine, the pipe body enters a plate edge roller press, rolling the curvature and diameter match. This molding method limits the thickness of the forming tube and the possibility of producing small diameter and thick walled tubes.
3, JCOE (compression molding) process
The prepared steel plate is transported to the molding machine, and the operating plate is used to move the steel plate to a pressing station, wherein the steel plate is pressed into the pipe body through a series of steps by an arc-shaped die pressing head. The hydraulic press is operated by two manipulators, which are first pressed to form a semicircle, that is, "J" shape, and the second manipulator transforms the steel plate to form the other half of the bend. The thickness of the stamper affects the roundness of the open tubular body and the thickness is preferably kept to a minimum. Edge rolling and three-roll process is similar.
4, C pressure molding process
The C-pressure forming process was first used by Pont-A-Mousson SA in France and is an effective method for producing large longitudinal welded pipes, especially for thick-walled pipe. Molding depends on high control accuracy and large pressure. After preloading of the plate by the roller bending machine, the plate was fed to the C pressure molding machine. Also, two operators were involved in forming the half of the plate on the first C press and then the other half on the other press, that is the first pressure into a "C" shape, and then pressed into "O" shape, so that the formation of an open circular tube. Both the tool and the platen hydraulic pad and stable suppression of small arc, while ensuring the length of the neat.
5, CFE (roll forming) process
Roll forming a full-roll molding and semi-roll forming of the points. The so-called semi-roll forming is only the general roll forming machine drive roller frame (that is, flat roller frame) between the idler roll row of small rollers instead to improve the molding conditions. Small roller can adjust the position for a range of pipe size, do not have to change. The whole row of roller molding is in addition to leaving a general roll machine in the first drive roller rack, the other rack all on behalf of a small row of rollers, small roller, especially outside the small roller, applicable to all Steel pipe, do not have to be replaced, so this method is beneficial to increase productivity.
