There are many types of tools that will cut steel. Band saw blades cut steel bars ad billets into pieces to be fabricated. End mills, gear cutters and lathe cutting tools fabricate the steel into some sort of tool or part. These blades, cutters and tools are usually made from some type of high speed steel. Common grades include M-2, M-4, M-48 and T-15. These steels are formed into a cutting tool with many different cutting configurations, but all of them will include some sort of tooth or cutting edge that has been fabricated to a sharp edge and heat treated to withstand high temperatures created by the friction between the tool and the work surface.
For a more in-depth explanation of high speed steels, their uses and heat treating, see the related link.
Plumbers normally use pipe cutters to cut pipe. The tool is faster, convenient and produces a clean cut.
hacksaw
A simple hack saw will get the job done.
A pipe cutter is the best tool to cut PVC pipe.
diagonal cutting pliers
We use a die of the proper size to cut threads on steel pipe. This pipe die can be turned by hand, or by machine. There are examples of this process in any good hardware or large home improvement store. They have pipe threaders on the premises, and they can thread most common pipe stock.
A stubber or tamper.
Cut the end of the cap off, about 1/2 inch back from the end and then cut the side of the cap. You should be able to peel the cap off of the pipe. If you have enough pipe, just cut the entire cap off and start with a clean section.
There are more than one kind of pipe. To which you want to know, is only a guess. A pipe is a tool used for smoking tobacco. It is a tubular device used for liquid flow.
A pipe
The tool used to correct internal hi-low when preparing a 4-in. steel pipe for welding is a four-inch grinder with cutting disc.
The tool you use for cutting wood is a a saw
A bread knife.