What is the minimum size coach screw rod needed for a 3-inch pipe?

The minimum size coach screw rod required for a 3-inch pipe is indeed 3/8". This specification is rooted in the need for adequate strength and stability when supporting the pipe. Coach screw rods, which are often used in mounting and securing pipes, must be able to handle the weight and potential stresses placed upon them.

For a 3-inch pipe, a 3/8" screw rod provides sufficient tensile strength and load capacity to support the piping system correctly. Using a size that is too small could lead to failure under load, which poses serious safety risks and compliance issues with installation standards.

While smaller sizes exist, such as 1/4" and 5/16", they do not meet the necessary strength requirements for a 3-inch pipe. Similarly, a 1/2" rod may be more than is needed, potentially increasing costs unnecessarily and complicating the installation process. Therefore, the choice of 3/8" balances both safety and efficiency in fittings and supports for a 3-inch pipe.