Connector Nuts

Trojan Special Fasteners Ltd routinely manufactures connector nuts to customer's requirements in multiple material and finish combinations. We manufacture a range of sizes of connector nuts in almost whatever length you require.

Connector nuts are also known as connecting nuts, connection nuts, coupler nuts, extension nuts, joining nuts, long nuts, studding connector nuts and coupling nuts. Such nuts are longer than normal nuts and are used to couple two male threaded rods (studding) together. The outside of the nuts is usually a hexagon so that a spanner can be used to hold it.

Trojan special fasteners can manufacture connector nuts which can mix two different sizes or even types of threads. Sight holes can be machined onto flats so that you can see the length of engagement. It is common for one side of double ended coupling nuts to be left handed and the other right handed. Coupling nuts where two different thread sizes and profiles are used are typically called reducing coupling nuts or simply hex reducers.

Coupling nuts can be used to tighten a rod assembly inward or to press a rod assembly outward.

They are typically available in two forms, one with a hexagon profile and one with a diameter profile:

Round Connector

Typically they are 3 times the length of the inner diameter, but we can machine other sizes, just ask! We can manufacture these in a limited number of sizes with a square profile if needed - but these are extremely rare. We can make almost any combination of internal and external diameter or profile you're looking for within available material specifications and finishes. At times customers ask these to be partially threaded on each end, sometimes with mixed thread sizes, pitches and a combination of left hand on one side and right hand on the other. Typically these are known as reducing coupling nuts.

Please be advised that the DIN 6334 standard that is often quoted is incorrect. This was a draft standard in 1943 but was never published as a standard and probably fell into disregard during the war. In various catalogues DIN 6334 is still used today by mistake or as a "sales argument". It must be noted that for this reason no official 'Grade' can be offered or marked for this fastener type and so whilst Trojan Special Fasteners Ltd manufactures these types of coupling nuts in metric thread form, we will always quote the material used.

In addition to standard preferred sizes, we also manufacture non preferred sizes and non standard or special thread and nut forms.

Trojan special fasteners can build additional features into fasteners, like collars, castellated, slotted portions and also cross drill and tap these:

Hex Connector or Coupling Nut with 3 points tapped for grub screws.

Reducing Connector Nuts

Reducing connector nuts or reducing coupling nuts are often used when we need to step down (or step up) from one size to another. They are used to connect two externally threaded parts. For example when one male thread is M16 and we need to couple it with an M12 bolt. This is easily achieved by us - we can mix and match whatever sizes, pitches and fit you prefer. All we ask is that you consider the spanner size that is most appropriate for you and also the overall length, because this determines the amount of thread engagement you will have.

Adapter Nuts

Adapter nuts are typically connector or coupling nuts used when we are changing the thread type from one fastener to another. For example we recently made a nut for a customer who had an 11/16 whitworth threaded bolt to which he was attaching a mount for a machine. The problem was, the newly manufactured mounts only came in a metric thread and it was too expensive and difficult to modify the male threaded part on the mount. Our solution... manufacture a connector nut in EN16T (605M36T material) with an 11/16 BSW thread on one side and M16 coarse thread the other side. We did this in just a few days. Our customer was very happy with the end result.

We can manufacture to the following specifications:

We can machine connector nuts to your dimensions, drawing or sample in a multitude of sizes, materials and finishes.