The check valve is a shut off device, developed for feedwater piping in high-pressure boilers and pumps. The check valve opens, automatically caused by the flow of the medium and shuts due to the gravity effect of the swing plate causing counter-pressure in case of flow interruption. Thanks to the glandless fitting of the valve shaft, a trouble-free and simple operation is guaranteed. Furthermore, needing no gland, leakage is quite impossible. The check valve is basically equipped with a self-sealing cover-plate. It is also employed as a safety device to check reverse-flow in pipelines carrying superheated steam and in long distance pipes systems with highest pressure ranges.

A butterfly valve is a valve which can be used for isolating or regulating flow. The closing mechanism takes the form of a disk. Operation is similar to that of a ball valve, which allows for quick shut off. Butterfly valves are generally favored because they are lower in cost to other valve designs as well as being lighter in weight, meaning less support is required. The disc is positioned in the center of the pipe, passing through the disc is a rod connected to an actuator on the outside of the valve. Rotating the actuator turns the disc either parallel or perpendicular to the flow. Unlike a ball valve, the disc is always present within the flow, therefore a pressure drop is always induced in the flow, regardless of valve position.