Durco was founded as the Duriron Casting Company in 1912. Its long history set the standard for ANSI chemical process pumps and robust plug valves. The brand is known for its durable designs, ease of maintenance, proven reliability, wide array of features and an extensive global support network. Complementary seals and seal systems are also available, enabling single-source convenience.

Highlights of Durco’s innovative history include the engineering and manufacturing of the world’s first Teflon® sleeve plug valve in the 1950s. The company has created unique materials, including Durimet-20 (Alloy 20) high alloy austenitic stainless steel — developed and patented in a joint effort with Ohio State University — and Durcomet 100 (CD4MCuN) duplex stainless steel in the 1960s. During the same decade, Durco introduced the first plug and butterfly valves fully lined with Teflon.

In 1997, Durco merged with BWIP, creating Flowserve Corporation.

Flowserve has supplied thousands of Durco G4BZ-HF Marathon Sleeveline HF alkylation valves to refineries throughout the world. Engineered for high-cycle, low-emissions service, this non-lubricated plug valve offers an extra measure of positive stem sealing reliability. It can be used with confidence in applications where tight shutoff and emissions containment are unconditional requirements to ensure safety.