Steel pipe is long, hollow tube that are used for a variety of purposes. They are produced by two distinct methods which result in either a welded or seamless pipe. In both methods, raw steel is first cast into a more workable starting form.
History of steel pipe
Steel pipe has been produced for about 150 years. The pipe sizes that are in use today in PVC and galvanized were originally designed years ago for steel pipe. The number system, like Sch 40, 80, 160, were set long ago and seem a little odd. For example, Sch 20 pipe is even thinner than Sch 40, but same OD. And while these pipes are based on old steel pipe sizes, there is other pipe, like cpvc for heated water, that uses pipe sizes, inside and out, based on old copper pipe size standards instead of steel.
Types of steel pipe
The two most common types of steel pipe as below:
Hot Finish Seamless Pipe (HFSM)
- Hot finish steel pipe is produced by boring out a the center of a solid steel rod.
Electric Resistance Welded (ERW) steel pipe
- Electric resistance welded pipe is produced by rounding out a steel sheet and joining the barrell of the pipe together longitudinaly with a welded seam. This is the most popular and cost effective way to produce steel pipe.
Uses of steel pipe
While this site deals primarily with pipes used for the transport of fluids, we would be remiss if we did not briefly acknowledge the importance of steel pipe as a structural memeber. Because it is hollow and has a relatively low strength to weight ratio, steel pipe can be designed by engineers and architects for many uses. It can be used on a large scale, such as the support pole of massive highway billboards. It can also be used on a small scale for everyday items such as a bicycle frame tube.
Steel pipe is often used as a fluid carrier pipe. The largest use is for “Line Pipe”. This pipe is used to convey petroleum products to their respective refineries. The most notable project of this type is the Trans-Alaska Pipeline. It consists of over 800 miles of transmission pipe with a diameter of 48″ and larger. There are also countless miles of smaller diameter ‘feeder pipes’.
Steel pipe can also be used to transport water. Although it seldomly carries water underground, it is a popular material for constructing fire sprinkler systems inside buildings. One reason for this is because it can easily be cut, groved and threaded to size on-site.
Steel pipe is often used as a casing pipe to protect water, sewer or other carrier pipes. Beacuse if it’s strength and rigidity, steel pipe can be pushed under roadways and railroads without traffic disruption. The most common method of this is called ‘jack and bore’ construction. The pipe is pushed with a hydraulic ram while an auger spins inside the pipe and carries the displaced soil back to the jacking pit where it can be easily removed.
It is also important to give steel pipe it’s due for it’s ability to be recycled. Most steel pipe, and any steel product for that matter, has high recycled content and a high reclamation rate. Industry has always been interested in recycling steel for economic purposes, but todays environmental concerns make it even more important. About 88% of all steel products and nearly 100% of steel products used in construction are recycled at the end of their useful life.