A Gate Valve is a sliding type of valve. In gate valves, the closing member is a metal gate. The gate slides down to close the valve. In fully open conditions, the flow area is equal to the area of the pipe and hence, there is negligible pressure drop across the valve. Gate valves should ideally be used as on-off valve, it is not advisable to use them as throttling valves because in partly open conditions, erosion of gate might take place. In partially open conditions, due to vibrations, valve is exposed to quick wear and tear. Also, during closing and opening, there is considerable amount of friction and hence, opening and closing these vales quickly and frequently is not possible. Gate valves are used to permit or prevent the flow of liquids and are typically for on/off control rather than flow regulation. Because of their ability to cut through liquids, gate valves are often used in the petroleum industry. ... Also, a partially open gate tends to vibrate from the fluid flow. These valves find their use in petrochemical industry due to the fact that they can work with metal-metal sealing. The main difference between a get valve and a ball valve is the way they close. A globe valve uses a plug (stem) that closes against the flow, and a ball valve has a gate(ball) that closes across the flow. Globe valves are good for regulating flow, whereas ball valves are better for on/off control without pressure drop.