Characteristics Of Automatic Welding Equipment For LSAW Steel Pipe

The West-East Gas Pipeline Project is a national key project, and it is also an unprecedented large-diameter lsaw steel pipe and high-pressure long-distance natural gas pipeline project in China. In order to ensure the welding quality, reduce the labor intensity of the welder and increase the welding speed, all-position automatic welding should be widely used in the project.

In order to meet the market demand, many factories ordered the M-300 automatic welding machine from the US CRC company. After the test welding of the pipe used in the West-East Gas Pipeline Project, the non-destructive testing of the weld, the mechanical properties and the mechanical test, satisfactory results have been obtained, which proves that the automatic welding has wide application prospects in pipeline construction.

1 Welding equipment1.1 system compositionThe M-300 consists of a welding trolley and a power junction box. Guide rails, cables, power supplies, protective gas regulating valves and flow meters are auxiliary components.The welding trolley is 559mm long, 584mm wide, 381mm high and weighs 20kg. The car is available in both clockwise and counterclockwise versions. They are mirror images of each other and can be welded simultaneously on both sides of the track on the same rail. The nose is connected to the trolley via a pivot and locking structure. The equipment attached to the handpiece includes a wire feed mechanism, a torch, a gas feed system, a forward sensing head, and vertical and horizontal adjustment devices. Under the combined action of these devices, the machine head can perform the following welding operations:1.) feeding welding current and shielding gas to the welding torch;2.) Provide appropriate wire dry elongation by adjustment;3.) Provide shielding gas for the arc and the molten pool;4.) continuous wire feeding to keep the filler metal welded in the weld bead;5.) Provide positive induction constant voltage control means;6.) Allow the operator to correct or improve the torch center position and arc length by horizontal or vertical adjustment.

All automatic control functions of the M-300 welder are performed by the control box, which includes various operations, fault diagnosis and release, servo and interconnection control circuits required to control welder travel, swing, wire feed, shielding gas and current.

Characteristics of high frequency straight seam welded pipe automatic welding equipment unit:The power junction box provides 28V DC to all working circuits of the M-300 welder. It includes a gas solenoid valve and a power contact relay. The power junction box has two operating voltages, one is 115V and the other is 220V. Depending on the country or region, plug the power supply box into the corresponding voltage position, you can choose 115V or 220V working voltage.

1.2 System FeaturesThe system is simple for the welder, except that the arc voltage is controlled by the power source, and other welding parameters, including welding speed, swing frequency, swing, wire feed speed, left and right dwell time, pit time, burnback time, etc., are all Control box control fixed on the trolley. The control box on the trolley can store four sets of welding parameters. Each set of welding parameters includes swing frequency, swing amplitude, wire feed speed, left and right dwell time, arc-extinguishing time, and arc-extinguishing time.

Only the welding speed cannot be stored. It is adjusted by the welding speed knob according to the actual needs of the welder and the welding procedure. Before welding, the required stored parameters can be directly used up through the menu; in the welding process, according to the weld bead, torch position, molten pool and other factors, through the increase and decrease buttons on the trolley control box The longitudinal and lateral adjustment devices, welding speed knobs, etc. modify the welding parameters in real time.

A worker from a steel pipe company, which is located in China.