What is a pipe fitter?
What is a pipe fitter or pipefitter? You could also add steamfitter, sprinkler fitter, gas fitter, and more to the mix. There are a lot of definitions of pipefitter or pipe fitter on the web. I am going to ramble in a quasi-definition because there is no simple answer. When unaware people are asked what a pipefitter might be, they often guess a plumber because they know a residential plumber uses pipe in his or her work. Add to that the UA is a combination of pipefitters and plumbers in the same union so that too make it easier to mash them all together. Then you have the pipe welders, who also can fit pipe as well as weld it, so some say that they are a pipefitter too. Some welders would agree. Some pipe fitters would not agree.
Many say that pipefitters do large welded pipe only. Many fitters would prefer to do the larger welded pipe only, but there is a thing about being "Home" and being a "traveler". A pipefitter will work a lot of types of pipe to stay home that he would not touch if he was on the road (being a traveler). Pipefitters often do prefer larger pipe because they can prep and fit the pipe, the welder tack it, then the welder takes over, pulls down his hood, and go into his world focused on the little white light and the time it takes him/her to complete a larger weld will give the fitter and apprentices time to get more stuff prepared.
Another reason what is a pipefitter is a difficult question to answer because there are so many kinds of pipefitting. There is quite a difference between mechanical pipe fitters and industrial pipe fitters. Mechanical pipefitters work on heating and cooling systems for the comfort of people. They pipe up smaller boilers and chillers plus the air handling units and components inside buildings. The term smaller can be confusing here because large buildings can have pretty good size boilers and chillers but industrial boilers can be the size of large buildings.
There is sometimes a mixture of pipe fitters on the same job. You can have a large industrial job going on with hundreds of industrial pipefitters on it and the contractor subcontracts to a mechanical company to put in a small boiler and chiller for heat and cool control rooms. They will bring mechanical pipe fitters with them. There are also animal processing plants that have mechanical, refrigeration, and industrial pipe fitters working there.
Industrial pipefitters work on industrial plants that may or may not include boilers and chillers but these boilers and chillers are for heating and chilling products or materials and not people. These boilers can be huge and the really big ones produce steam that runs the generators that provide us with electricity. Nuclear plants have lots and lots of pipe and so do the conventional power plants. Chemical plants are full of pipe moving fluids and gases to mixing vessels. Gas separation sites move natural gas through separation levels at different temperatures to change the state of gases to a liquid so they will precipitate out of the natural gas and be pumped to a different tank.
There are a lot of pipe fitters in the petrochemical industries. Besides refineries, you also have pipelines and a different group of welders that are called rig welders because they have their own trucks that are rigged up with all the tools they need to move along the pipelines welding it. Sometimes they have pipe fitters in their crew: Sometimes not.
Another aspect of piping is that you can move different states of matter through pipe. You can actually pump corn and plastic pellets through pipes. Corn and pellets are solids. We have already mentioned gases and liquids. So that is all three states of matter— gases, liquids, and solids going through pipe. Slurries, which is solids suspended in liquids, can also be through pipe.
There is another group of specialty pipe fitters who do something called high purity piping. I can't tell you what that really means except the final results is really pure. Now let's throw types of pipe in here because there are lots of types of pipe including carbon steel, various types of stainless steel, fiberglass, glass, plastic, flanged steel with plastic interiors. monel, incanel, plus titanium and more. I say they are specialists but when that work runs out, they will work as regular pipefitters until another job comes up. I'm sure there are more specialties around too. The pipe fitters doing jacket pipe could be considered as specialized. A jacketed pipe consist of a pipe surrounding another pipe. The interior pipe will contain a material of some kind that has to be kept at a certain temperature and the outside pipe contains a heated medium to maintain that temperature. If the system ever breaks down and the temperature in the inside pipe drops too low, the material inside will turn to a solid and it cannot be return to a liquid state. At great expense, it will have to be cut out and re-piped.
Then there is the part about how the pipes and fittings are fastened together. They can be butt welded, socket welded, screwed, soldered, brazed, glued, fused, compressed, etc. Each type of connection requires different training or understanding. Knowing one way doesn't always mean that you have a leg up on the other ways. That brings us to the pipe fabricator and there are curves to this category too. Pipe fabrication is making all the turns and intersections using the pipe itself. The pipe fabricator cuts miters or mitres to turn at different angles and they can use two or more pieces to make the turn. You can have a two piece 90° miter or a seven or eight piece miters turns and anything in between. Fabricators can make True Ys. Bull head plugs, Orange peel caps, 90° laterals, odd angle laterals, dummy support legs, pipe saddles, concentric reducers, eccentric reducers, and more from a piece of pipe. Shipyards is another place you will find lots of pipe fitters.
You might be surprised to know that there is quite a bit of trash talking that goes on about what and who is a pipefitter. Some have been put off their game when others have talked trash about their work. As you can see by all the different ways that pipe can be fit, there can always be a surprise at the next job. And there is always someone who says, And you call yourself a "pipefitter."
Yeah, the simple definition is pipefitters fit pipe together but. . .