Category Archives: Compression Fittings

Compression fittings are used in plumbing and electrical conduit systems to join two tubes or thin-walled pipes together. They are also used extensively for hot and cold water faucets, as well as for toilet stop valves. Deelat’s powerful compression fittings are built to stand the test of time without any signs of wear and tear.

Compression Fittings: Uses, Types and Benefits

Commonly used in conduit systems by plumbers, electricians and in the oil and gas industry, compression fittings are used to seal connections of piping or tubing. Generally, a compression fitting is made up of several pieces, including a compression nut and a copper ring.

The copper ring, or ferrule, and nut create a water tight seal around a pipe, when joined together. Essentially, the ferrule is fitted around the pipe or tubing, and it sits between the compression nut and receiving fitting. Then when the nut is fitted and tightened onto a receiving fitting, the ferrule clamps onto the pipe, and effectively seals the space that would have been left open between the pipe, nut and fitting.

Compression Fitting Diagram
Compression Fitting Diagram

Generally, there’s no need to over-tighten the seal, because over-tightening can lead to leaks. Instead, compression nuts are recommended to be tightened by hand, and then lightly with a wrench. Then, the seal can be tested and if water seeps through the fitting, the nut can be tightened until that stops. This installation can be done with standard tools, and it is much less time-intensive compared to other types of pipe fittings.

Compression Fittings: Common Types

There are two main types of compression fittings which are both readily available: Standard compression fittings and flared compression fittings. These two types are used in different applications, and they both provide advantages. The standard compression fitting is used most commonly by plumbers or in compressed air applications and they are slightly less robust compared to flared fittings.

The biggest difference between the two is that standard compression fittings do not require the pipe to be altered. With flared fittings, the tubing has to be altered to match the flare of the fitting. This flared joint creates a tighter, more reliable seal, which is why these compression fittings are more commonly used in oil and gas pipelines and chemical piping. In these applications, a more reliable fitting is necessary for added protection against costly or dangerous leaks.

Deelat Compression Fitting for Copper Pipe
Deelat Compression Fitting for Copper Pipe

Compression Fittings vs Soldering Fittings

Cost and ease of installation are two of the biggest advantages of using standard compression fittings. First, they’re generally a low-cost item, depending on size and materials used. A standard compression fitting made of durable copper may cost just a few dollars or less, and thus, it’s a low-cost solution for creating a reliable seal. Compared to soldered fittings, the ease of installation for compression fittings is also much simpler. There is no need for a heating element, and they can be installed using standard tools. That makes compression fittings ideal for application in areas where a hot solder presents a danger, i.e. in gas pipelines, and it makes disassembly much easier.

Deelat Compression Fitting - Female Elbow
Deelat Compression Fitting – Female Elbow

The biggest concern for a compression fitting is in durability and reliability. They provide extremely tight seals, but in some applications where the joint is prone to flexing, a soldered fitting will likely provide a sturdier fitting. Yet, on the other hand, soldered fittings are more time intensive and they can be more costly.

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