Blanking Plugs & Screws

Discover our comprehensive range of blanking plugs and locking nuts online now at Cromwell.co.uk. We stock high-quality components in a variety of thread styles and sizes to suit every task. Choose from popular, market-leading brands, like Kennedy®, SMC®, Camozzi® and more.

Why blanking plugs & locking nuts?

Blanking plugs are designed to plug or close excess production holes, protect against the ingress of dirt and moisture, or close off pipes and prevent leaks. They protect fingers against sharp edges in metal production and provide a clean finish or prevent tampering on panels and vents.

Locking nuts once fastened won't come loose when exposed to bumps and vibrations and can be relied upon to remain secure when used on pneumatic and hydraulic machinery and other similar items.

Blanking plug & locking nut types

There are a lot of styles to choose from when shopping for blanking plugs and locking nuts. Blanking plugs can also be purchased in various materials including nylon, brass and steel.

Blanking plugs

• Flanged plug   -   Featuring a round head to protect against leaks, these plugs are designed with parallel threads to allow repeated removal and refitting without threading or damage. They're frequently used on pneumatic and hydraulic machines.

• Threaded adaptor   -   These plugs are short and resemble the end of a bolt with the rest cut away. Designed for permanent closure, once in, they can be difficult to get out.

• Screw blanking caps   -   These serve the same purpose as a blanking plug, but feature a cap or head, much like a screw head to close off a hole completely.

• Blanking plug tube   -   Typically used to plug unused fittings, these plugs feature a tubed end to fill where the threaded end of a screw would normally go.

• Socket head plug   -   Designed with a tapered head for easy fitting, these plugs are typically used to close off pipe ends or prevent leaks.

Locking nuts

• Lock nuts with nylon inserts   -   Also called a self-locking nut, when tightened the insert is deformed between the surfaces of the nut and bolt to resist loosening.

• Jam nut   -   This low-profile design gets its name from the way that it is 'jammed' up against another nut to add security and resistance.

• Sawn nut   -   This type of lock nut features a slot halfway down its body to house a small screw. This screw is tightened once the nut has been closed in place to provide additional friction between the nut and bolt to prevent loosening.

FAQs

What's the difference between a lock nut and a normal nut?

While regular nuts can be loosened over time when subjected to torque or vibration, lock nuts are available in a range of styles which increase the amount of friction between the nut and bolt to prevent any loosening.

Are snap-fit blanking plugs any good?

The answer to this question depends on the application they're to be used for. Snap-fit plugs are made from nylon and aren't as strong as the metal alternative. However, they are low-cost and convenient to use and have their place when capping off unused outlets and production holes.