What is the difference between a ball valve and a gate valve?

Ball valves use a rotating sphere with a bore to control flow — they open and close quickly (quarter-turn) and are ideal for on/off applications. Gate valves use a sliding gate to stop flow and are better suited for fully open or fully closed service in larger pipe sizes where slow actuation is acceptable. Collins carries both types in a range of materials this includes carbon steel, stainless steel, and chrome-moly.