How Steel Pipe and Tubing Are Used in Industry
Steel pipe and tubing play important roles in industries such as construction, manufacturing, and transportation. They serve as conduits for fluid and gas transportation and structural components.
Both are cylindrical in shape, and adhere to standardized dimensions that facilitate their compatibility across industries. However, there are some significant differences between pipes and tubing.
Manufacturing Process
Steel tubing can be made using either the seamless or welded process. Seamless pipe is created by forcing a mandrel through the center of a solid billet of steel, which eliminates the need for a seam and offers tighter tolerances. Welded pipes are typically produced from a Steel Pipe/Tube coil of raw material that is cut to length, then bent and welded together.
The process of making both kinds of tubing starts with a large piece of raw steel known as an ingot. This is heated to very high temperatures until it is malleable. Rolling machines stretch the ingot into slabs, which are thin pieces of metal with rectangular cross-sections. More rolling devices flatten slabs into blooms, which are then rolled into shorter, thinner pieces called billets. These are then sliced into smaller pieces, called skelp, that can be used to make pipes.
For seamless tube, the skelp is forced over a mandrel in a mandrel mill. This creates an intermediate tube shell with a controlled standard outside diameter and wall thickness, and then it is passed through a multi-stand stretch-reducing mill to achieve the final size. The finished tube is reheated, straightened, and subject to inspection, hydrostatic testing and heat treatment. It is then trimmed and cut to the required length before shipping. The welded tubing manufacturing process involves passing strips of stainless steel through a series of rollers until it meets the desired size, then welding them together to create the desired shape.
Diameter
The diameter of steel tubes is a key factor that determines how much fluid or gas they can convey. This is why it’s important to know the precise outside and inside diameter of each pipe. It ensures that the pipes are compatible with the fittings and connectors they’re intended to be used with. Additionally, it plays a significant role in determining their pressure rating. For example, a pipe with a smaller gauge measurement will have a thicker wall to better manage high-pressure applications.
The dimensions of a pipe are defined by its outer diameter (OD) and wall thickness (WT). These measurements are exact in inches or millimeters, and are referred to as a schedule. Each schedule has a specific wall thickness that can be varied, allowing for diverse applications with varying pressure requirements. For example, a 1″ schedule 40 tube can have an OD of 1.315″ and a WT of 0.133″, resulting in an ID of 1.049″.
Understanding the differences between tubing and pipes helps to facilitate a seamless integration within projects. With a clearer understanding of their sizing and characteristics, individuals can make informed decisions on which product to choose based on specific project needs. This translates to efficient and consistent project delivery, from transportation to construction and manufacturing. For example, the load-bearing capabilities of steel tubes are crucial for building structures and foundations through a process called piling.
Wall Thickness
The wall thickness of a tube is measured using gauge measurements. A smaller gauge number indicates a thicker wall, which increases the strength of the product.
Steel pipes have a specific range of diameters and wall thicknesses depending on the type of application. For instance, low pressure applications such as sewage or irrigation may use pipe with a small gauge wall for cost efficiency. On the other hand, high-pressure applications like oil and gas pipelines require a more robust pipe to handle the increased stress that may occur during transportation.
The precise dimensions of pipes and tubing allow for seamless integration with other components in a system. This is accomplished by high carbon steel plate ensuring compatibility between the pipe’s outside diameter and the inside diameter of other fittings and connectors. In addition, standardized sizes and schedules enable efficient fluid transportation across a variety of industry applications.
The OD (outer diameter) and WT (wall thickness) of a steel tube can be easily determined by referring to the chart below. Each measurement corresponds to a specific schedule number and pipe size, which is based on the ANSI standard. For example, a 1″ OD x 16 BWG pipe will have a wall thickness of 0.065″.
Applications
Steel pipes and tubes play a large role in countless industrial applications. From large-diameter pipes used for oil and water transportation to small-diameter tubes utilized in precision instruments, their diverse sizes and shapes make them practical solutions for many different scenarios and specifications. For instance, pipe diameters can vary based on the type of product being transported and whether or not it will be buried underground. Moreover, steel tubing can be any shape from round to square or rectangular and even triangular.
The manufacturing process and the material used also play a critical role in the performance and versatility of these essential industrial components. For instance, pipes that require a high level of strength and ductility typically choose seamless steel products while those requiring load-bearing capacities will likely opt for welded steel. Additionally, a steel tube’s wall thickness plays an important role in its ability to withstand pressure and external force. This is why tube specifications often include an outside diameter (OD) and inside diameter along with a gauge measurement.
The versatile nature of tubes also makes them ideal for use in a variety of applications, from structural support to manufacturing vehicle frames and roll cages. These sturdy pillars serve as a key component in numerous projects, ensuring that buildings and bridges can safely hold heavy loads. Likewise, they are found in vehicles and aircrafts to provide rigidity and support for crucial mechanical parts like motor shafts, landing gear and exhaust stacks.