Skip to main content

What Pipe to Use for Your Shop's Compressed Air?

Many people use Schedule 40 PVC pipe and that choice is - OSHA ALERT - potentially dangerous. Under pressure, PVC can explode when it becomes brittle with age or exposure to UV light or when struck by an object. But there are a lot of shops piped with Schedule 40 PVC. If you choose to use it against all advice, at least consider the stronger Schedule 80 pipe and fittings, keep the pipe protected from things that may fall on it and don't hammer near it. PVC is smooth inside which means less pressure drop from friction.

There are ABS pipes, Dura-Plus and Chem-Aire, that are rated for compressed gas use. The cost is roughly twice that of Schedule 80 PVC. Dura-Plus comes in a metric size (colored blue) and an industrial size, colored gray; the blue pipe cannot be threaded for standard pipe threads. Chem-Aire pipe is green.

Schedule 40 black iron pipe is a popular choice and is very sturdy and durable. It's also heavy and awkward to install and will rust inside, not only adding scale to the air, but increasing friction and causing increasing pressure drops over time. Galvanized Schedule 40 is a better choice, but more cumbersome to work with and also requires some specials tools.

Copper pipe is lighter and easier to install, and comes in three types. Type L is identified with blue markings and Type K is identified with green markings; both are strong enough to use. Type M is marked red and is not recommended since it is only rated for 125 PSI; that won't leave much of a margin for error. Copper is smooth inside which means less pressure drop from friction; this matters for long runs of pipe.

Of course, you could always use stainless steel pipe and compression fittings or even the very cool (but ridiculously expensive) Garage Pak system which uses a coated aluminum pipe and special fittings. All that expense does buy a product that is easy to use.

There is also Compressed Air Systems which sells coated aluminum pipe. This looks like what I saw at Harbor Freight.

Comments

Popular posts from this blog

WTF is a Franzinator?

Sometimes the most useful things have the oddest names. Take the Franzinator, for instance. Named after Franz©, its curmudgeonly inventor, the Franzinator is a device used to separate moisture from compressed air. Having moisture in compressed air is not a a good thing, especially in painting where it contaminates the painted surface, or in media blasting where it causes the media to clump and not work as well. As well as causing rust in the air tanks and air tools, moisture is best removed. A number of methods have been developed from expensive refrigerated driers used to pre-condition air before it gets to the compressor, to simple mechanical separators that sit in the air line between the tanks and the air tool. Here is a tank that uses a chemical desiccant to dry the air. There are also ways to install the air lines that are intended to either cause moisture to condense or collect before it is sent to the air tool. A non-mechanical separator causes the moisture in the hotte

Keeping Your Compressor Quiet

Air compressors are noisy machines. The two most commonly used ways to quiet them down are to locate the air intake outside (not good for the neighbors) or to build some type of enclosure with sound deadening material inside; that usually causes overheating problems due to poor circulation. The best solution is to construct a silencer that uses the same principles as a gun silencer. But isn't that illegal? Only if you use it on a gun. We're using it on an air compressor. Still, this topic seems to be controversial, mostly by people who have a bury-your-head-in-the-sand approach to security and safety. Here are the materials: Pipe the same size the air compressor port will use, 16"-18" long. Some exhaust pipe, the same length as the other pipe. Some washers you have to make with a hole saw, enough to put one on each end and one every 1-1/2" that will fit around the air compressor intake port pipe and fit inside the exhaust pipe. Steel wool to fit betwe

Retrofit Hydroboost Brakes

Traditional power brakes have used engine vacuum to reduce the physical effort required to stop a car. Some high performance engines, because of the design of their camshafts, do not produce enough vacuum to used vacuum-powered brake power boosters. One alternative is to add a vacuum pump to the accessories driven by the engine. Another is to use the hydraulic pressure supplied by the power steering pump to power the brake booster. This device is called Hydroboost and it replaces the vacuum-operated brake booster. It provides more than twice the pressure than a vacuum diaphragm booster. There are commercial kits to use a hydraulic booster, like Vanco . They offer kits to match the car you are modifying. The most complete kits provide the Hydroboost unit, a new master brake cylinder, a power steering pump and the appropriate hoses with fittings and they are priced at around $900. You can see the parts of the kit by visiting this link . A nice step-by-step installation of the Vanco h