Lug butterfly valve type 038 DA alu-bronze disc DN50-DN300

  Datasheet (PDF)

The type 038 lug-style butterfly valve is a ductile iron quarter-turn isolation unit supplied with a factory-fitted double-acting (DA) pneumatic actuator, giving automated bidirectional shut-off and flow modulation in demanding industrial piping installations. The body is cast in EN-GJS-400 (GGG40) ductile iron and combined with an aluminium-bronze disc and a vulcanised EPDM liner, rated for working pressures up to 10 bar across a range from DN50 to DN300, matching pipe outside diameters of 63 mm to 315 mm.

The resilient seat delivers bubble-tight sealing in both flow directions, while the disc profile keeps the flow coefficient (Kv) high and the localised head loss low. The internal EPDM boot isolates the cast body and the stem bearings from the conveyed medium, preventing electrochemical corrosion and eliminating zones of stagnation. Drive is transmitted through a one-piece stainless steel stem to DIN 1.4021 (AISI 420), machined with a square drive profile that removes backlash over repeated quarter-turn cycles.

The top flange to DIN EN ISO 5211 couples the rack-and-pinion double-acting actuator directly to the valve, with no intermediate bracket or drive extension. The actuator reacts quickly to pilot air signals and holds a consistent operating torque at low air consumption through extended duty cycles. The threaded lug body centres the valve precisely between companion flanges drilled to EN 1092-2 PN6 and PN10 as well as ASME/ANSI Class 125 and Class 150, and the tapped lugs allow dead-end or end-of-line service at full differential pressure, so downstream pipework, pumps and vessels can be serviced without depressurising the upstream network.

The face-to-face dimension follows EN 558 series 20 (ISO 5752 series 20) for standardised interchangeability. Typical duties include industrial water treatment, cooling circuits, marine ballast lines and processing plants. Corrosion protection is powder epoxy coating, minimum 250 micrometres, RAL 5015, with CE marking.