Seamless steel pipe is alos called CDS pipes (Cold drawn seamless pipe). It’s is used widely in maching parts, shafts, bearings, cylinders having strength of 75000 PSD tensile. It is a solid carbon steel rod which is pushed on to the mandrel to form the shape of tube. It is availabe in different sizes.
Seamless steel pipe are ubiquitous and can be found underground and within residential walls, laboratories, and commercial and industrial structures. Seamless steel pipe transport fluids including water, natural gas, waste and air. Three manufacturing methods exist to produce steel pipes. Seamless steel pipes are produced using an extrusion mold. Welded steel pipes are produced by rolling a sheet of steel into a tube and welding the seam. Seamless steel pipes are less expensive. The third method is casting. Molten steel is poured into a casting mold. This is not very common today.
Increased Pressure Ratings of Seamless steel pipe
The largest benefit to using seamless steel pipe is the increased pressure ratings. When steel pipe is rolled and welded, the weakest point in the pipe is the welded seam. A seamless steel pipe does not have a seam, so the tensile strength is uniform around the entire circumference of the pipe. Steel pipe has nominal pressure ratings that are based on the tensile strength of the alloy (mixture of metals) and the wall thickness of the pipe. Using seamless steel pipe is more expensive but allows for smaller wall thicknesses and pipe weight, which can affect design and costs.
Uniform Shape of Seamless steel pipe
Because seamless steel pipe is a continuous extrusion of the alloy, it takes advantage of true roundness of the circumference. Welded seam pipe invariably is not as round in the cross sectional area as a seamless steel pipe because the welded pipe is wrapped around another form before welding. The welding adds heat, and the equipment adds stress to hold the pipe together. This process introduces variables that allow for warping of the roundness. Seamless steel pipe maintains the round cross-section, which is important during installation and the addition of pipe fittings.
Strength Under Loads of Seamless steel pipe
Although seamless pipe is the most expensive steel pipe, it is the most reliable with the fewest failure points. Because of this, pressure calculations are easier to perform because the weld quality is taken out of the equation. Another advantage to using seamless steel pipe is its strength under loading. Empty pipe has a certain weight that must be supported over long spans. When that pipe begins transporting material, the weight of the material must also be taken into account. Seamless steel pipe has strength benefits compared with welded pipe. Most pipe failures and leaks take place at the welded seam.