Fig200 API 6A Factory Best Price High-Pressure Union for Oilfield Hammer union A hammer union (also known as WECO union) is a heavy-duty, high-ressure quickc-onnect fitting for piping systems. It consists of three core parts: male sub, female sub, and a threaded hammer nut with lugs. Designed for rapid assembly/disassembly with a sledgehammer, it delivers reliable, leak-tight connections in harsh industrial environments. Hammer Unions can be used for cementing trucks, oil