As a complement to its range of butterfly valves the KSB Group, with branches in North and South America, has launched a special version for fire protection applications. The new BOAX-B FM valves, painted in red, are fitted with a specially designed gearbox. Suitable for an operating pressure of up to 16 bar, the valves are available from DN 40 to DN 300. The abbreviation FM stands for Factory Mutual, an international set of requirements for fire protection applications in industry and building services.
KSB’s design and the liner quality used ensure that the liner does not move, also under pressure, thus providing permanent and lasting tightness. The spherically machined valve disc and the liner, which is moulded accordingly, make for a tight shut-off at the stem passages preventing the stem from coming into contact with the fluid. The elastomer liners also provide sealing at the flanged line connections.
To enable power transmission between the blowout-proof stem and the valve disc, the engineers opted for a positive connection. The valve is actuated by a manual gearbox which is painted in red, too. A yellow flag of 100 x 100 mm, which is also visible from a distance, indicates if the butterfly valve is open or closed. A chain fastened to the gearbox prevents unauthorised actuation of the handwheel, and a locating device ensures that the manual gearbox is mounted in the correct position.