Wall outlet elbows are used to connect water supply lines to plumbing fixtures such as shower heads or faucets. The design requirements for wall socket elbows in terms of diameter depend on several factors, including the type of fixture it is connected to and the water pressure in the supply line.

In general, the diameter of the wall outlet elbow should match the diameter of the fixture to which it is attached to ensure optimum water flow and pressure. For example, wall outlet elbows for attaching standard shower heads are typically 1/2" or 3/4" in diameter, while wall outlet elbows for attaching bathtub sprayers may be larger, 1" in diameter.

In addition to the diameter of the fixture to be connected, the diameter of the wall outlet elbow should be sufficient to accommodate the water pressure in the supply line. A larger diameter may be required to prevent pressure drop and ensure adequate water flow to the fixture.

Additional design requirements for wall outlet elbows may include the angle of the elbow, the material used, and the type of connection, such as threaded or welded. The diameter of a wall socket elbow is an important consideration in its design and should be selected according to the specific needs and requirements of the plumbing system and fixtures it is connected to.