The main advantages of this type of valve are:
Easy to maintain and disassemble
Optimal as a shut off valve
Bidirectional
Low cost
Can be used with slurries and viscous liquids
Available in large sizes
Inherently fire-safe (when used with a metal sheet)
The disadvantages are:
Slow open and close time
Low-pressure limitations
Erosion of the seat and disk can occur
Poor throttling characteristics
Difficult to repair
– Standard gate valves: solid wedge, flexible wedge and split wedge. – Parallel slide gate valves. – Through conduit gate valves to API 6D and API 6A. – Single and double expanding gate valves. – Bolted bonnet, pressure seal and cryogenic designs are available
