Cast Iron Bellows Valve Type VG234 — Hermetically Sealing Valve for Steam and Heat Transfer
The cast iron bellows valve type VG234 is a bellows sealed valve PN40 with hermetic stem sealing and non-rising stem. Its body comes in three materials: grey cast iron EN-GJL-250, ductile iron EN-GJS-400-18-LT and cast steel 1.0619 (GP240GH). Disc and stem consist of 1.4021 (X20Cr13), the seat of stainless steel.
The metal bellows in X6CrNiMoTi17-12-2 seals the stem passage leak-free. It is certified to TA-Luft according to ISO 15848-1. The packing rings consist of graphite. The bellows valve with flange covers nominal sizes DN15 to DN250. It is available in pressure ratings PN10, PN16, PN25 and PN40.
Flange connections conform to EN 1092-2 (PN10 to PN25) and EN 1092-1 (PN40). In addition, the face-to-face length follows DIN EN 558 Series 1. Tightness is tested to EN 12266-1 Class A. The maximum operating temperature ranges from 300 °C to 450 °C, depending on body material. FERGO supplies the bellows valve high temperature ex stock.
Technical Data and Connection of the Cast Iron Bellows Valve
The cast iron bellows valve is available in nominal sizes DN15 to DN250. Pressure ratings cover PN10, PN16, PN25 and PN40. Flange connections conform to EN 1092-2 for PN10 to PN25 and EN 1092-1 for PN40. Furthermore, the face-to-face length follows DIN EN 558 Series 1. Actuation is by steel handwheel with non-rising stem.
The maximum operating temperature depends on the body material. It reaches 300 °C for EN-GJL-250. For EN-GJS-400-18-LT, 350 °C is possible. The cast steel version 1.0619 handles up to 450 °C. Therefore, the bellows globe valve ductile iron suits steam and high-temperature applications. It also covers varying pressure requirements.
Materials and Approvals of the Flanged Bellows Valve
The body is available in grey cast iron EN-GJL-250, ductile iron EN-GJS-400-18-LT or cast steel 1.0619. The choice depends on operating conditions. Disc and stem in 1.4021 (X20Cr13), together with the stainless steel seat, ensure wear-resistant shut-off. They also withstand thermal stress.
The bellows in X6CrNiMoTi17-12-2 seals the stem passage hermetically. It is certified to TA-Luft according to ISO 15848-1. As a result, fugitive emissions at the stem penetration are eliminated. The graphite packing serves as an additional safety seal. Moreover, the bellows valve TA-Luft meets the requirements for low-emission valves. It suits environmentally regulated installations.
Applications and Ordering of the High-Temperature Bellows Valve
The cast iron bellows valve protects steam lines reliably. It also protects hot water circuits, thermal oil systems and industrial process pipelines. The hermetic stem seal provided by the metal bellows prevents fugitive emissions. This gives a decisive advantage in installations subject to strict environmental regulations. In addition, the three body materials allow targeted selection. This depends on medium, temperature and pressure requirements. For custom solutions, project quantities or technical advice, the FERGO team is available.
