“If one worm clamp isn't cutting it, two worm clamps will.”
At the time of this writing, we carry three styles of clamps: Stainless Steel Worm Gear Clamps, Pinch Clamps and T-Bolt Clamps. Each of these are used in a similar fashion, to secure tubing or hose over a barbed insert fitting. The clamps accomplish this in a different manner unique to each clamp. Determining what clamp is right for your application is an easy task with the guide below. Links to the items mentioned in this guide will be included throughout the article.
These are often referred to as Screw Clamps or Jubilee Clamps; if you bump into one of those terms they’ll be a form of worm gear clamp. They are also referred to as Band Clamps, however band clamps can also be strap clamps.
Stainless Steel Worm Gear Clamps have a zinc coating (galvanized) for increased resistance to corrosion. They are frequently used in agriculture, automotive, and industrial applications. They are made of a steel band, one end of which contains a screw; when the screw is turned it acts as a worm drive, pulling the threads of the band and tightening it around the tubing. These types of clamps are mostly used with ½” or larger tubing.
Worm gear clamps are easy to use, remove and are completely reusable. Other than a flathead screwdriver, no additional tools are needed to install one. Worm gear clamps can loosen over time due to external forces exerting tension on the screw, so it’s a good idea to check the tightness of the screw from time to time to ensure it is tight and secure. Worm clamps can also apply uneven pressure which may not be ideal in all applications; this will cause some tubing distortion, though generally nothing severe in a low pressure irrigation system.
Though no specialty tool is required to install or remove these, Murray does produce a clamp key that can speed up installation and removal: Murray Clamp Key.
The biggest criticism of worm gear clamps is that they can loosen over time and can slightly distort the tubing/hose over time since most of the tension is on one side of the clamp.
These are often referred to as Oetiker Clamps, Ear Clamps and Crimp Clamps. These types of clamps have a protruding “ear” that is squeezed together with a crimp tool in order to close the clamp over the hose/tubing it is meant to secure. These types of clamps are more frequently used in permanent applications since they are essentially a one time use item. They also work exceptionally well in low pressure situations, such as drip irrigation. They are considered amongst the easiest to use and amongst the most effective over the long-term.
Murray, the manufacturer of our pinch clamps, uses patented design to reduce mis-crimps. They also make two different crimp tools to help with installing clamps in tighter spaces. The crimp tools are at these links: Murray Side Jaw Pinch Clamp Crimp Tool and Murray Pinch Clamp Crimp Tool.
Other than being a one time use, the biggest drawback to these clamps is that it can be difficult to get the crimp tool into tight spaces -- this is more of a problem seen in automotive applications, but it can be a problem in irrigation systems, particularly when clamping in a valve box or similarly small space.
T-Bolt Clamps are often referred to as Racing Camps or EFI Clamps. They are a good balance between worm gear clamps and pinch clamps. Unlike worm gear clamps, these provide for 360° of tension so you don’t end up with distorted hose. Unlike pinch clamps, these can be reused at any time and are easy to remove from tubing and hoses.
The biggest drawback to T-Bolt clamps is generally only in their price, as they do cost a bit more than the other two clamp styles we carry. It has been reported that these can also lose a bit of tension over time like worm-gear clamps, but without the associated distortion of the tubing.
If you have an odd size tubing for which there are no available clamps or need a special sized clamp for a particular application, Murray produces a create-a-clamp kit that allows you to create a custom sized worm gear clamp. The kit comes with 10' of banding, adjustable fasteners and band splices. The kit is available at this link: Create a Clamp Kit.
Clamp Features Chart
*can be difficult if space is tight
Clamp Specifications and Compatibility Charts
Below are some specification charts for our clamps. Included are the open and closed diameters of various clamps and the sizes of tubing, oval hose, layflat, and FlexNet they are compatible with.