The stem of a gate valve is the tool that allows the slab to move up and down, making it possible to open and close the flow of the valve.
Due to the importance of its use, the materials used for the production of the stems must have remarkable mechanical strength characteristics such as tensile strength, yield strength, elongation, reduction of area , impact test, hardness, etc., which ensure a safe position over time.
Its design assumes that, it has different levels of threaded parts, in which a locking ring called “stem head” is mounted at the end of the stem, a band with a trapezoidal pitch that determines the opening and closing distance, a short threaded part in the tail of the stem. The trapezoid thread fraction must be suitably protected during any nickel plating
