ASME/ANSI B18.2.2 Hex Slotted Nuts Supplier In China

ASME/ANSI B18.2.2 Slotted Nuts and Castle Nuts are designed for threaded connections where the nut needs to be mechanically secured after tightening. Their defining feature is the series of slots formed around the top of the nut, which allows a cotter pin or similar locking device to pass through the nut and the mating bolt or stud. This provides a positive mechanical locking method and helps prevent the nut from rotating away from its installed position under vibration or repeated movement.

Unlike a standard hex nut, the slotted or castellated top is an integral part of the nut design rather than an additional locking component. The nut can first be tightened to the required position and then aligned with a cross-hole in the mating fastener so that the locking pin can be installed through the slot. This configuration is particularly useful for assemblies where the connection must remain mechanically retained while still allowing later removal during maintenance.

The appropriate nut size, thread series, material, and mechanical grade should be selected together with the mating bolt or stud and the required locking method. Carbon and alloy steel versions are suitable for many mechanically loaded connections, while stainless steel options can be selected where corrosion resistance is important. The slotted or castellated configuration makes these nuts especially valuable for joints where vibration, rotation, or serviceability are important considerations.

Specification of ASME/ANSI B 18.2.2 Hex Slotted Nuts:

ASME/ANSI B18.2.2 Slotted Nuts and Castle Nuts are manufactured with an external hexagonal body and a slotted or castellated upper section designed to accommodate a locking pin. The nut geometry is coordinated with the applicable inch-series thread dimensions so that the nut can be installed using a standard wrench or socket before the locking device is fitted.

The specification includes the nominal thread size, thread series, width across flats, nut height, slot configuration, and material or mechanical grade. Carbon steel, alloy steel, and stainless steel can be selected according to the required strength and service environment. Surface treatments such as plain, zinc plating, black oxide, or other protective finishes may also be specified according to the material and application.

Dimension Chart of ASME/ANSI B18.2.2 Hex Slotted Nuts:

The ASME/ANSI B18.2.2 dimension chart provides the main measurements required to select a slotted or castle nut for an inch-series threaded connection. In addition to the conventional nut dimensions, the slot geometry is important because the slots must align with the cross-hole in the mating bolt or stud to allow the cotter pin to pass through the completed assembly.

The principal dimensions include nominal thread size, width across flats (s), nut height (m), width across corners (e), slot width, and slot depth. The thread size determines compatibility with the mating fastener, while the width across flats determines the required wrench or socket. Nut height and slot dimensions affect the position of the locking pin and should be checked together with the cross-hole location of the bolt or stud.