Two Way Reversible Lock Nuts
Hex Centerlock All Metal Lock Nuts
Two-way Reversible Lock Nuts (also known as Centerlock Nuts) get their name because of the distorted thread in the middle and ability to be used either top-up or top-down. The distorted internal threads increase resistance on the mating part. This creates a locking mechanism in the center of the nut, which helps it resist loosening from vibration. With the locking mechanism being at the center of the nut, centerlock nuts can be started from either side.
Having the locking portion within the hex nut offers several benefits, including versatility in application, application speed (which helps on assembly lines), and application environment versatility. All metal lock nuts can be used in high heat or highly corrosive applications where a nylon insert would not be suitable. Bolts or Screws used with Two Way Reversible Lock Nuts can also be shorter than the nut because the locking occurs in the center. For this reason, the end of the bolt or screw does not have to extend beyond the end of the nut.
All Centerlock nuts feature indentations on the nut's outside flats to mark them as center locking nuts. They would otherwise be indistinguishable from standard hex nuts.
Two-way reversible lock nuts are available in 18-8 stainless steel, 316 stainless steel, and zinc plated steel.
18-8 or 304 grades of Stainless steel are suitable for many general purpose applications, especially freshwater and non-salt water wet environments. Corrosion-resistant and durable, 18-8 stainless steel is equivalent to the A2 grade of stainless steel.
For much more corrosive environments, such as in saltwater or marine applications, 316 stainless steel is the ideal choice. 316 Stainless steel is equivalent to A4 stainless steel.
Zinc Plated Steel
Zinc is by far the most common and economical type of plating for fasteners. The zinc plating adds a protective "sacrificial" top layer against corrosion while also adding a shiny finish to the fastener. Zinc plating is ideal for indoor use where it won't be constantly exposed to harsh elements.
What is a reverse lock nut?
Reversible lock nuts are nuts with distorted threading in the middle of the nut, which causes a locking action when a screw or bolt is threaded through it. Because the distortion is in the center, reverse lock nuts can be started from either side. They are also known as two-way and center lock nuts.
What is a center lock nut?
Centerlock nuts are all-metal lock nuts with distorted threading in the center of the nut. The distorted threading increases the friction between the nut and screw being fastened through it, increasing the nut's resistance to loosening over time. Because the distortion is in the middle of the nut, it can be installed from either side. This is why center lock nuts are also known as two-way or reversible lock nuts.
How do you tighten a centerlock nut?
Center lock nuts can be tightened by turning them clockwise onto the bolt, screw, or stud they are being installed on. They are installed the same way as standard hex nuts and can be started from either side of the nut. Unlike standard hex nuts, however, center lock nuts are much harder to unfasten.
What are locking nuts for?
Lock nuts are an easy to use, cost-effective solution to protecting against vibration-related loosening. They're used to protect applications from loosening over time.
How do you use lock nuts?
Most lock nuts are used the same way traditional nuts are; by simply fastening them to the opposite side of a bolt. The locking action activates after the nut is fastened down. The exception to this is castellated nuts and slotted nuts, which needs a hole drilled into the bolt and a cotter pin to finish installation.