Why You Should Consider Using Grooved Clamp Couplings On Your Compressed Air Lines And How To Install Them

Posted on: 3 June 2015

Compressed air is sometimes called the fourth utility due to its importance to industrial production. Unfortunately, this valuable resource is also wasted due to indiscriminate use and leaking. While controlling use is more a matter of policy and procedure, leaks can be eliminated through rehabilitating or replacing existing pipes and fittings. One time-tested, effective means of reducing compressed air leaking is using grooved clamps to join pipes. If your facility uses compressed air, then you should consider refitting it with grooved clamp couplings. Below is more information on this technology as well as how to install a grooved clamp joint:

Why grooved clamp coupling is better

Traditionally, compressed air pipes are joined using threaded connections or welds. While these are sufficient in many environments, they both possess various weaknesses that often make them less-than-ideal for use. For example, threaded connections are notorious for permitting air leaks, even when sealed with dope and thread tape. Welded connections are permanent and difficult to remove, as well as requiring skilled workers for installation.

Grooved clamp coupling, on the other hand, possesses the advantages of both threaded connections and welded connections without the disadvantages of either. Grooved clamp couplings can be removed quickly, yet they also offer a strong, leak-proof seal that can be installed by nearly any worker in a facility. Installation is fast and simple; it only requires a few tools and a minimal amount of training.

Installing grooved clamp coupling – tools and materials needed

  • Grooved clamp coupling
  • Gasket
  • Grooved pipe
  • Socket set
  • Torque wrench
  • Mineral spirits
  • Shop towel

Installing grooved clamp coupling – step-by-step procedure

1. Choose your grooved clamp coupling and gasket – the most time-consuming step in installing grooved clamp coupling is making sure you are choosing the correct coupling and gasket for your compressed air pipe. Once the pipe is in in-place, grooved and ready to be coupled, you will need to select a coupling and gasket that satisfies the following characteristics:

  • Properly sized coupling and gasket – this requires knowing the manufacturer's recommendations about sizing the coupling based on pipe and/or groove diameters. Most couplings will be about a size larger, diameter-wise, than the pipe, but always consult product literature to be certain.
  • Appropriate gasket material – gaskets come in a variety of materials including EPDM rubber, silicone and nitrile rubber. For compressed air applications, it is important to know the content of vaporized oil and other contaminants; some materials, such as EPDM, will break down in the presence of petroleum products. Other considerations when choosing gasket material include heat exposure and uncontrolled environmental factors such as humidity and ultraviolet radiation.
  • Rigid or flexible coupling – couplings are available in both rigid and flexible design. If your compressed air system is exposed to vibration or other shock hazards, then a flexible design may be ideal for your usage. However, be sure to weight the cost and benefits since rigid couplings are generally less-expensive.

2. Align the pipe ends, and install the gasket – the gasket must be placed on clean, oil and dirt-free metal to provide a complete seal. Thoroughly clean the pipe ends with an appropriate solvent, such as mineral spirits, to remove any contaminants. In addition, if your pipe has burred or sharp edges, be sure to remove them with a deburring tool, grinder or file before installing the gasket.

Once the pipe ends are cleaned and deburred, slide the gasket over one end of the pipe, and move it back away from the end of the pipe to protect it from damage. Once the gasket is on the pipe, align both ends of the pipe so they abut one another. Keeping the pipe ends aligned, carefully slide the gasket over until it rests directly above the joint. Center the gasket, and be sure it is perfectly aligned around the entire circumference of the joint.

3. Install the coupling – after positioning the gasket and pipe, open the coupling so its jaws are extended and place it in position over the joint. Align the jaws so they will drop down into the grooves, then close the coupling. With an appropriately-sized socket, tighten the fasteners holding the jaws in position; be sure to tighten both sides evenly, and don't over-tighten. Consult the product information to determine how many foot/pounds of torque to apply to the fasteners, then torque the fasteners accordingly.

4. Inspect and test your installation – once the clamp is installed and properly tightened, inspect the joint for potential problem points such as kinked gaskets or uneven fasteners. Introduce a light flow of compressed air through the line, and listen for hissing. Provided the installation passes the inspection and test, you are now ready to place the line into full operation.