When you first look for stainless steel piping, whether for a desalination plant, an oil rig, or a nuclear power plant, one of the first questions you should ask yourself is: "Do I need seamless pipe or welded pipe? Both types offer different advantages and are therefore suitable for different applications and environments. Many factors should be considered when selecting the right one for a particular project. Next, the steel pipe products supplier will share with you.
Let's start with seamless pipe. As the name implies, seamless pipe is a seamless pipe without any seams or welds.
Seamless pipe can be manufactured using a variety of different methods, depending greatly on the desired diameter or wall thickness to wall thickness ratio. Typically, the process of manufacturing seamless tubes begins with the casting of crude steel into a more viable form - a thermoset billet. It is then stretched and pushed into or out of the form. The hollow tube then undergoes an extrusion process, which forces it through a die and mandrel. This increases the inner diameter and reduces the outer diameter.
Seamless steel pipe is commonly used to transport fluids such as water, natural gas, waste and air. It is also often required in many high-pressure, highly corrosive environments, such as in the oil and gas, power generation and pharmaceutical industries.
Benefits: Seamless pipe has the distinct advantage that there are no seams, and therefore no chance of weak seams. This means that seamless tubes typically withstand 20% higher working pressures than welded tubes of the same material grade and size.
Resistance: Seamless seams mean that seamless tubes can offer higher corrosion resistance because there is less chance of things like impurities and defects occurring in the weld seam.
Less testing: It goes without saying that seamless tubes do not need to be tested for weld integrity - no weld means no test.
Welded pipes come in three forms: OD welded, ID welded or both sides welded. The common denominator is that they all have seams.
The manufacturing process for welded pipe begins with rolling the steel coil to the desired thickness to form a flat bar or plate. It is then rolled and the seams of the resulting tube are welded in a chemically neutral environment.
Regarding which type of steel is weldable, austenitic steels are usually the most weldable, while ferritic steels can be welded in thin sections. Nowadays, duplex steels are considered fully weldable, but they do require more maintenance than austenitic steels.
It is believed that the technology for manufacturing welded tubes has advanced considerably in the last few years. Arguably the most important advancement has been the development of the use of high frequency currents as a welding technique. This has greatly improved the ability of welded tubes to avoid corrosion and seam failure.
While it is true that the seam of a welded tube is theoretically weaker, today the manufacturing methods and quality assurance procedures are far superior. This means that there is no reason why this performance should not be made inferior to seamless pipe in many industries, as long as the temperature and pressure tolerances specified for welded pipe are not exceeded.
Cost: A major advantage of welded pipe is that it is the cheapest of all pipe types and is more readily available.
Consistency: It is well established that the wall thickness of welded pipe is much more consistent than that of seamless pipe. This is because the manufacturing process starts with a single steel plate.
Surface quality: Avoiding the extrusion process also means that the surface of welded pipe is also smoother than seamless pipe.
Speed: Because the manufacturing process is simpler, shorter lead times are required for welded pipe procurement.
As a steel pipe products manufacturer, no matter which seamless or welded pipe you need, RENPU can supply and deliver seamless and welded pipe. If you want to get more information aboutcarbon steel pipe products for sale, welcome to contact us.