Open Pinch Valve The open body construction is designed for applications with relatively low pressures and low temperatures when the flowing medium is non-hazardous. The open body construction is light and it is very easy to access for service. The available valve diameters begin with 80 mm. The standard body material is mild steel, but AISI316 bodies can also be delivered upon request. The open body features with the advantage of being able to tolerate misalignment and vibration.