Waveguide flange



![Figure 4. Plastic caps over disconnected flanges prevent dirt[4] and moisture entering the waveguide, in addition to protecting the face of the flange from damage.](/uploads/202502/20/Protective-plastic-cap-on-waveguide-flange3215.jpg)
A waveguide flange is a connector for joining sections of waveguide, and is essentially the same as a pipe flange—a waveguide, in the context of this article, being a hollow metal conduit for microwave energy. The connecting face of the flange is either square, circular or (particularly for large or reduced-height rectangular waveguides), rectangular. The connection between a pair of flanges is usually made with four or more bolts, though alternative mechanisms, such as a threaded collar, may be used where there is a need for rapid assembly and disassembly. Dowel pins are sometimes used in addition to bolts, to ensure accurate alignment, particularly for very small waveguides.