What Is a Locating Ring?
A locating ring is a vital component used to align the molding machine with the mold. Typically, two or four rings are attached to the mold to ensure precise alignment between the nozzle of the molding machine and the mold’s sprue. Proper alignment is crucial to prevent leakage of injection material and defects in the molded product, which can occur due to misalignment between the mold’s sprue bushing and the injection nozzle of the molding machine.
Uses of Locating Rings
Locating rings are mounted on the top of the mold to align the injection nozzle of the injection molding machine with the entrance of the sprue bush and the hole in the fixed side mounting plate of the mold. Their use not only ensures high-precision positioning between the injection molding machine and mold but also facilitates the mounting of the mold to the machine.
Types of Locating Rings
There are four main types of locating rings: Type A, Type B, Type AJ, and Type BJ. The AJ and BJ types differ based on the inner shape of the rings, with the AJ type having no taper and the BJ type having a taper. This differentiation likely originated from the need to facilitate mold fitting when locating rings were first used in aligning injection molding machines with molds. In the field of machining, tapered connections have long been used to ease machine fitting. The revised Type A is now defined as a tapered type, while Type B is defined as a type without an internal hole.