Mud gate valve repair kits: telling Demco DM 2000–5000 parts from DM 7500 parts

DM mud gate valves sit on the mud manifolds and standpipes of a great many rigs, and their seats and gates wear on a predictable cycle. The trap when ordering spares is that the line comes in two families that look alike from outside and share no wear parts. Order a kit for the wrong family and it will not go into the valve.

/01Two families.

/02Telling them apart.

The quickest test is the seat. A DM 2000–5000 seat is a single moulded piece with two pins and a slot for the gate; a DM 7500 seat is a ring insert that sits inside a separate steel wear ring in the body. The next test is the number stamped on the part: four digits and a dash suffix (1887-002, 2207-021) is the 2000–5000 family, while seven digits and a -01 suffix (2171112-01) is the 7500 family. Cameron numbering adds a J00 prefix to the four-digit parts, so J002207-021 and 2207-021 are the same seat.

/03Part numbers by size.

For the DM 2000–5000 family, the 2" seat assembly is the 1876 series in ductile iron, steel or 316 stainless with Buna-N or Viton, the 2" gate is 1887-002 (nickel-plated) or 1887-008 (316 stainless), the stem 1931-002 or -008, and the stem seal assembly 1949-001 or -006; the 4" full-port steel and Buna-N seat is 2207-021. For the DM 7500, the gates are 2171112-01 (3"), 2171267-01 (4") and 2171108-01 (5"), and the seat inserts include 2139742-01 (2") and 2139746-01 (4"). The DM 7500 wear ring sets the minimum bore: 1.97 in, 2.98 in, 3.97 in and 5.17 in for 2", 3", 4" and 5".

/04Reading a kit number.

DM 7500 kits follow a pattern that encodes the size: J025177-00X74 is a minor kit and J025177-10X74 a major kit, with X the size in inches. So J025177-00274 is the 2" minor kit, J025177-00474 the 4" minor and J025177-10474 the 4" major. DM 2000–5000 kits are in the J025216 series — J025216-13221 is listed as a 4" major kit — but the size code in that series is not consistent between sources, so confirm the valve size and series rather than decoding the number.

/05Ordering repair parts.

Send the valve size, the pressure series (2000, 3000, 5000 or 7500 psi), any number stamped on the body, gate or seat, and the elastomer the service needs. Each of our listings states the makes we can supply for that part — Demco and unbranded aftermarket on most — so say which you require. Complete mud gate valves are listed at 7,500 psi from 1-13/16" to 5" with butt-weld, flanged or union ends; the wider gate valve markings are covered in reading an API 6A nameplate.