Valves in high-pressure piping systems can comprise a primary valve body and a bypass. When a valve is closed, a valve member, such as a gate, a ball, or a disc, can seal a bore of the valve, thereby preventing passage of fluids such as liquids or gases through the bore. When a closed valve is subjected to a high pressure differential, a large unbalanced force acts on the valve member of the valve. The unbalanced force can make the valve difficult to open due to friction acting on the valve member. The effect can be exacerbated as the cross-sectional area of the valve bore and the pressure differential increase. Large-diameter valves can comprise a smaller bypass which can be opened to allow the pressure to equalize on either side of the larger valve, thereby alleviating the unbalanced force. It can be desirable for the large-diameter valve to have the bypass attached to the primary valve body, such as in applications where space and equipment clearance are limited. However, typical bypasses can be difficult and expensive to manufacture. Typical bypasses are constructed from common pipe fittings such as elbows and nipples which are welded or mechanically coupled together. The welded and mechanically coupled connections can be prone to fabrication defects, misalignment between pipe fittings, and leaking.
For example, in some applications, a pair of threaded nipples can be screwed into a pair of internally threaded holes defined by the primary valve body. The threaded nipples and the threaded holes commonly use a tapered thread pattern, such as a National Pipe Taper (NPT) thread standard. The threaded nipple must be fully screwed into the threaded hole in order to fully seal; however, depending on a depth and indexing of the internal threading, a flange of the threaded nipple may not be indexed properly to connect with an adjacent elbow. The depth of the internal threading can be cut deeper to correct for indexing of the elbow, but the depth of the internal threaded holes must be substantially similar so that the threaded nipples extend outwards from the primary valve body at substantially the same distance or misalignment can occur between the elbows. Because these variables are interrelated, properly aligning and sealing each of the common pipe fittings of a typical bypass can cause extensive rework and manufacturing delays.