Welding of stainless steel pipes
Manufacturing conditions
The starting material for carbon steel pipes is cold rolled strip (strip) with a width of 24-1400 mm, and stainless steel pipes are strip with a width of 50-330 mm. The carbon steel tubes, which arrive at the cold rolling mill, are welded with high-frequency currents. Stainless steel pipes are welded by argon-arc welding. Equipment for all welding methods is used as part of tube electric welding mills. Only the welding part of the mill is changed when changing to another method.
Pipe forming mill
Continuous tube-forming mills form tube billets Ø 6 - 529 mm from coiled flat strip. First the stainless steel strip from the coil is attached by a loading device to the coil unwinding mechanism, straightening, trimming of the strip, welding of the strip ends, removal of burr after welding at the joints, creating loops in the loop forming machine with pulling rollers. The belt edge is trimmed with disc cutters with an edge cutter, the edges are cleaned with metal brushes. And the last thing is the feeding of the sliver into the tube forming mill. The supplier guarantees high quality in accordance with GOST and international standards. Buy today. Price is optimal.
Types of welding
Machined billet can be welded by resistance welding, radiofrequency or arc welding in an inert gas environment. The process is directly affected by the type and calibration of the working tool, the number of idle and working stands in the mill, as well as the distance between them, and the setting of the mill. Hot-rolled strip after welding is not deburred.
High-frequency welding
Apply current of up to 450 kHz, it is brought to the edges of the workpiece by contact and inductive methods. The most widely used is an induction current, using two or three inductors. Under the influence of high-frequency current in the metal of the workpiece, an electromotive force arises. The current flows from one contact to the other in two ways: along one edge to the joint and back, and around the perimeter of the pipe. To reduce the current, a ferrite core is inserted inside the pipe, increasing the inductive resistance for the current to flow around the perimeter, and the current flows freely along the edges of the pipe, heating it to the welding temperature. It is necessary to keep a minimum clearance between the core and the pipe of 2-3 mm (although in practice it is 3-5 mm) in order to avoid electrical breakdowns. The edges of the welded workpiece are heated to the melting temperature of the metal. After that the edges are pressed together by means of crimping rolls and spliced.
Contact Electric Welding
A high-frequency current is applied to the edges of the workpiece. In this process the edges are heated at the contact points to welding temperature, pressed together and welded. Current is supplied from the secondary winding of the welding transformer through rings, separated by an insulator. At the point of convergence of the edges, the resistance is greatest, and in this place there is the greatest heat generation and heating of the joint to the welding temperature.
Transformer
In a welding transformer, the current that is supplied to the primary winding is converted to a current of greater strength. The transformation is expressed by a coefficient, which is 40. In a 60-200V transformer winding, the voltage and amperage take on a value of 1.5-5V and 38,000A, respectively. The edges are squeezed by squeezing rolls. Then the workpiece is fed into the mill to the forming rolls, which have a guide washer. Stainless steel pipes are welded on the welding rolls. After welding, the pipe is straightened on a straight head that goes into the pipe welding machine.
Inert gas arc welding
It is used for pipes with Ø 6-102 mm. There are countries where arc welding is used for pipes up to Ø 500 mm, with wall thickness of 0.2-5 mm, and for the chemical industry 0.4-3 mm.
Furnizor
Are you interested in welding of stainless steel pipes? Stainless steel pipe welding from the supplier "Auremo" meets GOST and international quality standards. We offer to buy stainless steel from the specialized warehouses of the supplier "Auremo" with delivery in any city. Wholesale customers the price - preferential. Buy today.
Buy at a discounted price.
Auremo supplier's warehouse offers the widest selection of stainless steel tubes. Always in stock welded pipe, the price is due to the technological features of production without the inclusion of additional costs. Buy stainless steel pipe today, the price is optimal from the supplier. We are waiting for your orders. We have the best price-quality ratio for the entire range of products. In touch with experienced managers - will promptly help you buy stainless steel in bulk or in installments. Regular customers can buy stainless steel with a discount discount, the price - the best in this segment of rolled products. Supplier "Auremo" is a recognized expert in the market of rolled tubes. Buy stainless steel tubing today. Wholesale customers the price - preferential.
