When a welded tee connection is created on a pipeline run, the strength of the run section is decreased by the hole that is created. This loss of strength must be compensated for in one of two ways: either by initially selecting and utilizing pipe that includes excess wall thickness in the run section and/or the branch section, or if that’s not possible, by adding additional thickness to the newly created connection. One way to add this additional thickness is to install a reinforcing saddle.
Typically fabricated using an extrusion process, a reinforcing saddle is a non-pressure retaining structural component installed over a welded tee connection to supply adequate reinforcement for the joint. Because reinforcing saddles are not designed to contain pressure, they are supplied with a “weep” hole to prevent the possibility of pressure build-up between the saddle and the pressure-containing pipe. There are two types of reinforcing saddles: Partial and Full Encirclement.
Unlike reinforcing saddles, hot tap fittings are designed to be pressure retaining. Once the hot tap is performed, the fluid pressure acts on the inside and outside of the run pipe and the fitting becomes a primary pressure boundary. For this reason, the design of the hot tap tee must include reinforcement calculations to ensure adequate thickness for the run and branch.
Typically used when the branch size is less than half of the run size, WeldFit also offers partial reinforcing saddles. Made in accordance with ASME B31.3 and B31.4 codes, we have the capabilities and facilities to make practically any common size, wall thickness, and material specification.