AS9120B, ISO 9001:2015, and FAA AC 0056B ACCREDITED

What are Well Nuts and their working?

A well nut is a removable rivet nut that is composed of two parts. One part consists of a flanged rubber section made of EPDM Neoprene, and the other part is a brass insert nut. Well nuts only necessitate one end of the hole to be exposed, allowing operators to use them for blind fastenings. Well nuts, or rubnuts, rubber nuts, or rawlnuts as some may call them, are fasteners employed in applications that require an element to be connected to a surface. Versatile in function, well nuts can be installed very easily.

Well Nut Installation

First, a hole with the same diameter as the rubber portion of the insert must be drilled into the installation material at hand. Then, the insert can be slid into the hole wherein the flange is the only part of the nut that is exposed. A hole should be drilled into the material you want to attach the well nut to if it has not been done already. You can now slide a washer onto the machine screw. You must use a washer to apply pressure onto the flange portion of the well nut, preventing the well nut from loosening during installation. At this point, you can line up two holes and push the machine screw that matches the threading of the well nut through the holes. As you drive the machine screw into the threads, the well nut tightens and the rubber portion will begin deforming, creating a stronger hold. 

Well Nut Properties

One of the most advantageous qualities of well nuts is their water resistant characteristic. During installation, the rubber portion that deforms over and into the hole creates a waterproof barrier, completely sealing the surface. However, there are several factors that may affect a well nut’s ability to create a waterproof seal.

If the rubber on the well nut dries out, it may cause the well nut to crack, creating leaks that will eventually necessitate the replacement of the entire assembly. Salt water environments reduce the service life of the rubber portions. Under pressure, the rubber may further deform, loosening the seal on the hole. Lastly, the screw may loosen on the nut, which may lead to accidental shocks and vibrations on the assembly. When the screw loosens, the rubber takes on its original shape and breaks the seal on the hole.

Where Are Well Nuts Found?

Due to their water resistant qualities, they are often found in a variety of applications. They can also be used to mitigate vibrations and shocks that are typically imposed on industrial machinery. Well nuts also serve as insulators between materials to prevent galvanic corrosion, a type of corrosion wherein two distinct metals are submerged in water and corrode. 

While diverse in function, well nuts are not everlasting components. As such, it is important to routinely check well nuts and their corresponding parts to ensure that your assembly is properly working. If you find yourself in need of a reliable distributor for all your procurement needs, you can steadily depend on Fastener Orbit Services.

Fastener Orbit Services is a premier supplier of NSN parts, connector components, and other related items, all of which have been subjected to rigorous quality assurance measures, tests, verifications, and assessments. Due to our steadfast commitment to quality, we proudly operate with AS9120B, ISO 9001:2015, and FAA AC 00-56B certification and accreditation. Peruse our ever-expanding inventory at your leisure and fill out an RFQ form when you find an item that meets your operational requirements. As you complete the form, we ask that you provide as many details as you can regarding the parts you wish to purchase. Kickoff the procurement process with a competitive quote for your comparisons and within 15 minutes, a dedicated representative will reach out with a sourcing solution that keeps your unique needs in mind.


February 1, 2022

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