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The closing element of a stop valve (Globe Valve) is a plug-shaped valve disc whose sealing surface is flat or conical; the valve disc moves in a straight line along the center line of the valve seat. The type of movement of the valve stem – (commonly known as a hidden stem) – also includes lift-and-rotate stem types, which can be used to control the flow of various types of fluids such as air, water, steam, various corrosive substances, mud, oils, liquid metals, and radioactive materials. Therefore, this type of stop-check valve is very suitable for cutting off, regulating, and throttling. Due to the relatively short opening and closing stroke of the valve stem in this type of valve, as well as its highly reliable shut-off function, and because the change in the valve seat orifice is proportional to the stroke of the valve disc, it is very suitable for regulating flow rate. Common faults of globe valves, causes, and methods of prevention and troubleshooting: Sealing surface leakage – Incorrect flow direction of the medium can erode the sealing surface; install the valve according to the flow direction indicators or its structural design, i.e., the medium should enter from below the valve seat (except in some designs where the medium enters on the sealing surface and exits below it). Dirt tends to accumulate on flat sealing surfaces; leave a small gap when closing the valve and flush it several times before closing fully. Misalignment of conical sealing surfaces – Proper assembly is necessary; the valve stem, valve disc, throttle cone, and valve seat must all be on the same axis. Any bending in the valve stem should be corrected. Damage or aging of the lining sealing surface – Regularly inspect and replace the lining; ensure that the closing force is appropriate to avoid damaging the sealing surface. Failure due to clogging of the needle valve – The wrong type of valve was selected, one that is not suitable for media with high viscosity. Small-diameter valves may get clogged by foreign objects; these should be removed by disassembly. Valve disc or throttle cone detachment – Valves with rolled or wire-connected closing elements should be avoided when dealing with highly corrosive media; if such elements detach, they need to be repaired, and the wires should be replaced with stainless steel wires. Damage to the internal valve stem nut or valve stem’s tapered threads – Improper selection or corrosion by the medium can cause this issue; the correct valve structure should be chosen ； The operating force should be low, especially for small-diameter stop valves and throttle valves ； If the trapezoidal thread is damaged, it should be replaced promptly. If the flow control is inaccurate or the scale is not aligned with the zero position, or if the scale is missing, it must be adjusted to be aligned with zero. If the scale is loose or missing, it needs to be repaired and replaced. If the flow control cone is severely eroded, proper material selection and heat treatment are necessary, as well as ensuring the correct direction of flow and proper operation