Welding stainless steel pipe

Production conditions

The starting material for pipes of carbon steel is cold-rolled strip (the strip) 24−1400 mm, and for stainless steel pipe 50−330 mm. tubes of carbon steel, which are cold rolling mill, welded by high frequency currents. Stainless steel tubes produce TIG welding. Composed of electric welding tube mills used equipment for all welding methods. Changing only the welding part of the mill when you switch to another method.
Preparation for molding

Truboprovodnye continuous mills are used for forming tubular workpieces Ø 6 — 529 mm of coiled flat ribbon. First, stainless steel tape from a roll loading device is attached to the mechanism of unwinding rolls, spend editing, trim strips, welding the ends of the tape, deburring after welding the joints, creating a loop in the accumulator with stretching rollers. Cut edge ribbon disk cutters with cromcastle, sanded edges with a metal brush. And the last is feeding tape in truboprovodny mill.

Welding

The processed workpiece can be welded by resistance welding, RF or arc in inert gases. On the process directly influenced by the type and calibration of the working instrument, the number of blanks, and the work stands in the mill, and the distance between them, setting up camp. Hot-rolled strip after welding is not sanded.

Welding by high frequency currents

Apply current to 450 kHz, it is applied to the edges of the contact and induction methods. The most widely induction supply current using two or three of inductors. Under the action of high frequency current in the metal workpiece an electromotive force. The current passes from one contact to another in two ways: along one edge to the seam and back, as well as around the perimeter of the pipe. To reduce the current inside the pipe enter the ferrite core, this increases the inductive resistance for current that passes along the perimeter, and the current passes freely along the edges of the pipe, heating it up to welding temperature. Need to maintain minimum clearance between the core and the tube 2−3 mm (although in practice it 3−5 mm), in order to avoid electrical breakdowns. Edges to be welded of the workpiece is heated to a temperature of melting metal. After that edges are compressed crimp rolls and spliced.

Electric resistance welding resistance

The high-frequency current is supplied to edges of the workpiece. The edges are heated at points of contact to welding temperature, compressed and welded. The current supplied from the secondary winding of the welding transformer through the rings separated by insulator. At the convergence of the edges of the resistance is greatest, and in this place there is the greatest evolution of heat, and heating the joint to welding temperature.

In the welding transformer current that is supplied to the primary winding is converted into a current of greater strength. The transformation is expressed by a coefficient, which is equal to 40. In the winding of the transformer with a voltage 60−200 V, the voltage and the current gain value respectively 1.5−5 and 38000 In A. Edges are squeezed by shrinking the rolls. Then the billet enters the mill for welding stainless steel pipes, resistance in the molding rolls, in which there is a guide washer which directs the workpiece in the welding rolls. After welding the pipe on the right is ruled by the head, which is part of the electric welding apparatus.

Arc welding in inert gases

It is used for production of pipes with Ø 6−102 mm. There are countries where using arc welding are made of pipe Ø up to 500 mm, with wall thickness of 0.2−5 mm, and for the chemical industry 0,4−3 mm.

To buy, price

In stock, LLC «" always available high-quality metal. We offer welded stainless steel tubes at the best prices. It is formed taking into account technological features of production and does not include additional costs. All products are certified. The timing of orders is minimal. Wholesale buyers get a preferential discount.