(1) Wedge type single gate valve
① The structure is simpler than that of an elastic gate valve;
② At higher temperatures, the sealing performance is not as good as elastic gate valves or double gate valves;
③ Suitable for high-temperature media prone to coking.

(2) Elastic gate valve
It is a special form of wedge type single gate. Compared with wedge gate valves, they have good sealing performance at high temperatures and are less likely to get stuck when heated; Suitable for media such as steam, high-temperature oil products, and oil and gas, and suitable for areas with frequent switching. Not suitable for media prone to coking.

(3) Double disc gate valve
① The sealing performance is better than that of wedge gate valves, even if the angle of the sealing surface and the seat fit are not very accurate, it still has good sealing performance;
② After the sealing surface of the ram is worn, the metal pad at the top and bottom of the spherical center can be replaced with a thicker one, which generally does not require welding or grinding of the sealing surface. This is difficult to achieve with single rams and elastic rams.
③ There are more parts than other forms of gate valves;
④ In addition to being suitable for media such as steam and oil, it is also suitable for areas with frequent switching and media with high wear on sealing surfaces. It is not suitable for media that are prone to coking.

(4) Parallel gate valve
① The sealing performance is worse than other forms of gate valves;
② Suitable for medium with low temperature and pressure;
③ Except for the rams with fixed plates on the two rams that are not easy to fall off, the rams that are fixed with lead wire are easy to fall off and unreliable to use.
④ The processing and maintenance of the sealing surface of the gate and valve seat are simpler than other forms of gate valves.