Appleton Century Crofts RB250-150 IMC Reducing Bushing Conduit

Appleton RB250-150 Reducing Bushing

The Appleton RB250-150 is a chromate-coated iron reducing bushing designed for hazardous-location conduit systems. It connects 2-1/2 inch IMC or threaded RMC to 1-1/2 inch conduit. This fitting is intended for electrical contractors and maintenance teams working in classified areas where explosion-proof connections are required. It is not for buyers who need a coupling for non-threaded conduit types or larger trade sizes.

Female-to-Male NPT Thread Adaptation

The critical specification is the hazardous-location thread pattern: 1-1/2 inch FNPT to 2-1/2 inch MNPT. This female-to-male configuration only matches conduit entries and fittings cut to those exact NPT dimensions. Using it with straight-thread or metric entries will not create a compliant seal. The overall length is 1-1/4 inches, which determines the engagement depth inside the enclosure or fitting body.

Simple Threaded Installation

Installation requires hand-tightening the male end into the larger female hub and the smaller conduit into the female end, then securing with a strap wrench to the manufacturer’s recommended torque. The chromate, powder-coat and electroplated finish resists corrosion but can gall if threads are cross-started or over-torqued. The most common issue is damaging the coating or stripping threads when the bushing is forced into misaligned entries. Weighs 0.82 lb.