The Differences Between Welded and Seamless Pipes

Stainless steel piping utilizes an economical cross-section of steel to create a common and important product in manufacturing and construction industries. Industrial pipes are widely used in architectural applications and civil engineering projects ranging from sewage to oil and gas and compressed air systems. However, stainless steel piping is also used to make stair railings, window guards and contemporary furniture. Whatever your project, you will find stainless steel piping to be a strong and durable product.

The two common types of stainless steel used in industrial piping are 316 and 304, along with welded and seamless variations determined by the application, which production method is best adopted.

In this blog we will look at the difference between welded and seamless stainless-steel piping and how each product benefits their industry applications.

  1. Appearance

The most striking difference between a stainless-steel seamless pipe and a stainless-steel welded pipe is appearance.

Welded stainless steel is polished and mirror-like, while seamless stainless steel is matte and off-white. You may decide to choose one material over the other based on their appearance value.

  1. Seamless Stainless-Steel

The stainless-steel seamless pipe is a long strip of hollow steel that is free of joints. Thick seamless stainless-steel is economical and durable, with a wide range of applications, while thin seamless stainless steel comes with a higher price tag and usage limitations.

Stainless-steel seamless pipes are made through a process of cold rolling, cold drawing or hot extrusion, where there is no welding point on the tube. Generally, seamless stainless-steel has uneven wall thickness, low brightness, a high production cost around sizing, along with plenty of pits and black spots on the inside and outside that are hard to remove. However, where appearance is not important, seamless stainless-steel makes a superior product that is for high pressure and high strength applications.

  1. Welded Stainless-Steel

Welded steel pipes, also known as welded pipes or tubing, are longitudely welded after being rolled to a precise diameter in a continuous process.

Welded steel pipes have a straightforward production process, and come in many varieties and specifications, but as a material the strength is less than seamless steel. That said, the quality of welds is being continuously improved, and the variety and specifications of welded steel pipes are only increasing, making this steel material applicable in more and more industries, including high-pressure environments and sanitary tubing.

  1. Performance and Price

Seamless pipes perform better than welded pipes in terms of durability and pressure and high temperature resistance. The manufacturing process of welded piping is constantly improving, resulting in mechanical properties that in many cases match or approach the benefits of seamless pipes. However, for the time being, the more complicated production process still results in a more expensive pipe. For some applications, seamless pipes may also lack the appearance value of welded pipes. If you are having trouble deciding, consider the following factors:

(1) A welded tube is generally preferred as a decorative tube, product tube and sanitary tube, or wherever a project demands a good surface effect.

(2) For low pressure fluid transportation, you can also depend on the material characteristics of stainless-steel welded pipes.

(3) For large scale pipelines, as well as pipelines that require high temperature, high pressure, and high strength properties (such as important industries like oil refineries and nuclear power plant boilers) stainless steel seamless pipes are the obvious choice.

Speak to the Experts

Air Energy supplies a comprehensive range of industrial pipes and air compressors, as well as industry-specific specialist and ancillary products. Our professional products are supported by 20 years of experience across a wide variety of technical industries across Australia. We offer fast, dependable, cost-effective solutions to suit your project specifications. Should you need assistance, please do not hesitate to  contact us today.