Gone are the days when pipes were welded mechanically. This is because pipes now have a far wider scope today and will have to be able to hold tough in a wide range of conditions. From high vacuum to heavy pressure, pipes must operate under stressful conditions and successfully transport gas or oil or water or whatever you intend to use them for. For this, we use the Arc Welding, Tig Welding, MIG Welding and other advanced electric arc or oxyacetylene welding methods.
This is where we cut the pipes to fit your length requirements. Cutting pipes 101 is to be straight when you cut. The cut must be a true circle and must be cut in a plane perpendicular to the centreline of the pipe. The pipes must be cut with any of the following: a strip of heavy paper, cardboard, leather belting, or sheet gasket material with a straight edge longer than the circumference of the pipe to be welded.
Clean demarcations, clear understanding of the requirement and good craftmanship is required. We at Pothigai Engineering Works can take care of all the three. Pipe with a wall thickness exceeding 1/8 in. (3.2 mm) should be cut first with a straight cut, then beveled with a hand torch to a 30 to 35-degree angle, leaving a shoulder of approximately 1/8 in. (3.2 mm).
For the weld to be proper, it is important to first clean the pipe and remove any rust, dust, dirt, scale, or any other foreign material on the pipe or in the vicinity of weld inside the pipe. We’ll do it with perfection, and we keep it simple. We use a file, wire brush, grinding disk, or another type of abrasive. I we’d used oxyacetylene cutting to bevel the pipe, then the oxide formed will be completely removed before welding.
From boiler tubes to sand blasting, we used multiple methods to clean the insides of the pipe as well. Taking extra care to clean the scarf surface and make sure that the pipes are completely cleaned can help save a lot of cost and effort afterwards.
This is a very important step. Based on plans and design, we’ll have decided which two pipes are being welded together. Depending on the method of welding and whether there’ll be backing rings, the distance between the pipes is set, and they’re mounted on a pipeline up clamp or a makeshift setup using the pipe sections and jigs. Our methods are precise, and we take immense care while setting things up before starting to weld pieces together.
We then will decide which method and means to use to weld. This purely depends on the needs for the weld. Where are the pipes going to be? Is it a closely packed space? What will the pipes be carrying? There are all considered before settling on the position of the weld, and what tools to use. Usually, manual oxyacetylene process and manual shielded metal-arc process are used. Automatic & semiautomatic submerged arc, inert gas metal-arc.