Coliter ® Top Mounted Eccentric Hemisphere Valve – Hard-Sealed, Online Maintainable for Slurry & Scaling Media
DYQ3/6/940F/H/Y Top Mounted Eccentric Hemisphere Valve – Double Eccentric Design with Metal-to-Metal Sealing for Zero Leakage in Harsh Industrial Environments
The Coliter® DYQ3/6/940F/H/Y Top Mounted Eccentric Hemisphere Valve is a robust quarter-turn valve engineered for demanding applications involving abrasive slurries, scaling fluids, solid-laden media, and corrosive chemicals. Featuring a double eccentric structure, the metal ball crown is offset from both the sealing axis and rotation center. This design ensures that during opening, the spherical core immediately disengages from the seat—eliminating friction, reducing operating torque, and preventing seal damage. When closing, the hardened alloy ball crown gradually contacts the floating metal seat, generating a shearing action that cuts through scale, fibers, or particulates to achieve bubble-tight shut-off (Class IV–VI). Both sealing surfaces are surfaced with wear- and corrosion-resistant alloys such as Stellite or tungsten carbide, enabling reliable performance at temperatures up to 600°C and in aggressive environments. A standout feature is its top-entry, online maintenance capability: after system depressurization, the valve cover can be removed to lift out the ball crown and support body for inspection or repair—without disconnecting the valve from the pipeline, minimizing downtime. Available in ductile iron, carbon steel (WCB), or stainless steel, with sizes from DN50 to DN2000 and pressure ratings of PN10–PN40 (1.0–4.0 MPa), it complies with GB/T 12237, GB/T 13927, and API 6D. Widely used in power plant ash handling, metallurgy, mining, chemical processing, and wastewater treatment, the DYQ series delivers exceptional durability, tight sealing, and serviceability where conventional valves rapidly degrade.
Installation diagram
Product Description
Top mounted eccentric hemisphere valve is a new product developed successfully by absorbing and digesting the advanced technology at home and abroad. It is a new type of valve that the metal ball crown is fixed on the eccentric ball. Through the 90 degree rotation of the eccentric crankshaft, the valve can be opened and closed. The metal seat in contact with the sealing surface of the metal ball crown floats in the axial and radial direction to compensate the coordination between the ball crown and the valve seat. The valve is used in petroleum, chemical, electric power, metallurgy and other industries. The valve structure adopts the eccentric wedge tightening principle, and achieves the purpose of locking, adjusting and closing through the transmission mechanism. The sealing ring and ball crown are metal face ring with hard surface contact seal. When the double eccentric structure valve is opened, the ball body is hidden in the valve cavity, with large flow section, and the valve is not scoured, and the flow resistance is small. When the valve is closed, the valve core will not be washed. When the valve is closed, the spherical surface of the valve core will gradually move along the valve seat. It has the shear function, which can effectively remove the scaling obstacles and achieve reliable sealing. It is especially effective for medium transportation which is easy to scale. The hemisphere of the valve is to fix the metal ball crown on the eccentric ball. Different alloy ball crowns are installed on the ball. The valve seat is also made of corresponding surfacing alloy. After special treatment, the sealing surface is assembled into various types, such as anti-corrosion, wear-resistant, high temperature resistant, etc., to meet the needs of different occasions. The valve seat and the ball crown have compensation. When the valve seat is worn, it can be reliably sealed and the service life can be prolonged by turning a little when it is closed. The biggest feature of the valve is that the valve can be inspected and maintained online after the pressure relief of the device system under working conditions. During the maintenance, it only needs to open the valve cover to lift out the ball crown and support body, and does not have to unload the whole valve from the pipeline.
| Nominal pressure PN(MPa) | DN | Size | |||||||
| L | D | D1 | D2 | b-f | Z-Φd0 | TORQUE | Reducing | ||
| H DYQ340Y1.0 F | 50 | 178 | 165 | 125 | 100 | 18-2 | 4-18 | 57 | 38 |
| 65 | 190 | 185 | 145 | 120 | 18-2 | 8-18 | 90 | 49 | |
| 80 | 203 | 200 | 160 | 135 | 20-2 | 8-18 | 122 | 62 | |
| 100 | 229 | 220 | 180 | 156 | 22-2 | 8-18 | 192 | 74 | |
| 125 | 254 | 250 | 210 | 184 | 22-2 | 8-18 | 260 | 100 | |
| 150 | 267 | 285 | 240 | 211 | 24-2 | 8-22 | 324 | 123 | |
| 200 | 292 | 340 | 295 | 266 | 24-2 | 8-22 | 647 | 150 | |
| 250 | 330 | 395 | 350 | 319 | 26-2 | 12-22 | 1105 | 200 | |
| 300 | 356 | 445 | 400 | 370 | 26-2 | 12-22 | 1502 | 250 | |
| 350 | 450 | 505 | 460 | 429 | 26-2 | 16-22 | 1946 | 266 | |
| 400 | 530 | 565 | 515 | 480 | 26-2 | 16-26 | 3164 | 303 | |
| 450 | 580 | 615 | 565 | 530 | 28-2 | 20-26 | 3793 | 334 | |
| 500 | 630 | 670 | 620 | 582 | 28-2 | 20-26 | 4769 | 385 | |
| 600 | 800 | 780 | 725 | 682 | 34-2 | 20-30 | 7529 | 487 | |
| 700 | 900 | 895 | 840 | 794 | 34-5 | 24-30 | 11420 | 538 | |
| 800 | 1000 | 1015 | 950 | 901 | 36-5 | 24-33 | 15840 | 589 | |
| 900 | 1100 | 1115 | 1050 | 1001 | 38-5 | 28-33 | 24200 | 684 | |
| 1000 | 1200 | 1230 | 1160 | 1112 | 38-5 | 28-36 | 32000 | 779 | |
| 1200 | 1300 | 1455 | 1380 | 1328 | 44-5 | 32-39 | 39770 | 874 | |
| 1400 | 1500 | 1675 | 1590 | 1530 | 48-5 | 36-42 | 60000 | 976 | |
| 1600 | 1800 | 1915 | 1820 | 1750 | 52-5 | 40-48 | 81000 | 1166 | |
| 1800 | 2000 | 2115 | 2020 | 1950 | 56-5 | 44-48 | 120000 | 1460 | |
| 2000 | 2200 | 2325 | 2230 | 2150 | 60-5 | 48-48 | 212000 | 1580 | |
| H DYQ340Y1.6 F | 50 | 178 | 165 | 125 | 100 | 18-2 | 4-18 | 68 | 38 |
| 65 | 190 | 185 | 145 | 120 | 18-2 | 8-18 | 110 | 49 | |
| 80 | 203 | 200 | 160 | 135 | 20-2 | 8-18 | 145 | 62 | |
| 100 | 229 | 220 | 180 | 156 | 22-2 | 8-18 | 230 | 74 | |
| 125 | 254 | 250 | 210 | 184 | 22-2 | 8-18 | 310 | 100 | |
| 150 | 267 | 285 | 240 | 211 | 24-2 | 8-22 | 390 | 123 | |
| 200 | 292 | 340 | 295 | 266 | 24-2 | 12-22 | 770 | 150 | |
| 250 | 330 | 395 | 350 | 319 | 26-2 | 12-22 | 1325 | 200 | |
| 300 | 356 | 445 | 400 | 370 | 28-2 | 12-26 | 1800 | 250 | |
| 350 | 430 | 520 | 470 | 429 | 30-2 | 16-26 | 2400 | 266 | |
| 400 | 530 | 580 | 525 | 480 | 32-2 | 16-30 | 3900 | 303 | |
| 450 | 580 | 640 | 585 | 548 | 40-2 | 20-30 | 4550 | 334 | |
| 500 | 630 | 715 | 650 | 609 | 44-2 | 20-33 | 5730 | 385 | |
| 600 | 800 | 840 | 770 | 720 | 54-2 | 20-36 | 9040 | 487 | |
| 700 | 900 | 910 | 840 | 794 | 50-5 | 24-36 | 13700 | 538 | |
| 800 | 1000 | 1025 | 950 | 901 | 42-5 | 24-39 | 19000 | 589 | |
| 900 | 1100 | 1125 | 1050 | 1001 | 44-5 | 28-39 | 29000 | 684 | |
| 1000 | 1200 | 1255 | 1170 | 1112 | 46-5 | 28-42 | 38500 | 779 | |
| 1200 | 1300 | 1485 | 1390 | 1328 | 52-5 | 32-48 | 47700 | 874 | |
| 1400 | 1500 | 1685 | 1590 | 1530 | 58-5 | 36-48 | 72000 | 976 | |
| 1600 | 1800 | 1930 | 1820 | 1750 | 64-5 | 40-55 | 97000 | 1166 | |
| 1800 | 2000 | 2130 | 2020 | 1950 | 68-5 | 44-55 | 145000 | 1460 | |
| 2000 | 2200 | 2345 | 2230 | 2150 | 70-5 | 48-60 | 246500 | 1580 | |
Performance standard
| Design and manufacture | Inspection and trial | Flange connection | Structural length |
| GB/T12237-2007 | GB/T13927-2008 | GB/T9113, GB/T79, HG20596, SH3406 | JD-2004 |
Main performance specifications
| Nominal pressure PN | 1.0 | 1.6 | 2.5 | 4.0 |
| Maximum working pressure at normal temperature | 1.0 | 1.6 | 2.5 | 4.0 |
| Shell strength test pressure | 1.5 | 2.4 | 3.8 | 6.0 |
| Airtight test pressure | 0.6 | 0.6 | 0.6 | 0.6 |
| High pressure seal test pressure | 1.1 | 1.76 | 2.75 | 4.4 |
| Applicable temperature | Soft seal: -40℃～200℃; Hard seal: -29℃～600℃ | |||
| Applicable medium | Natural gas, water steam, oil products, acids, alkalis, pulverized coal,coal ash Waste slag, mud, granular, fiber and other media. | |||
| Transmission form | Worm gear drive, electric drive, pneumatic drive, hydraulic drive | |||
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Faq - Frequent questions
Introduction to Eccentric hemisphere valve
Coliter®’s eccentric hemisphere valves deliver exceptional shut-off performance in abrasive, corrosive, and high-solid media such as slurry, wastewater, pulp, and mining fluids. The series includes the DYQ3/6/940F/H/Y top-mounted eccentric hemisphere valve and the PBQ3/6/940F/H/Y side-mounted type, both featuring a hardened alloy-sealed rotating hemisphere that minimizes seat wear through an offset (eccentric) design. Available with manual, worm-gear, pneumatic, or electric actuation, these valves offer bubble-tight sealing (Class IV–VI), full-port flow, and resistance to clogging. Constructed from ductile iron, carbon steel, or stainless steel with tungsten carbide or Stellite coatings, they operate at PN10–PN40 (1.0–4.0 MPa) and temperatures up to 250°C. Ideal for power plant ash handling, sewage treatment, metallurgy, and chemical processing—where reliability under extreme conditions is critical.
