What are the differences between Globe valve and Gate valve?

Gate Valves have a large slab that lowers down into a cavity at the bottom of the valve. They care sometimes fitted with a drain so you can bleed the cavity dry to prove that the valve is sealing correctly and no flow can by-pass it. This is useful for when you have to do work on a tank and need to be sure no product will go into the tank through that valve. Gate valves also open fully and can allow a pig to pass unobstructed.

Glove valves have a plunger like assembly that lowers down into a sealing face. They are usually used where flow control is required and you do not need to pass a pig through the line.

Here is a picture of a globe valve

and a Gate Valve

Drew