Our central workshops: meticulousness and precision

At the end of 2023, our workshops completely overhauled and restored a head valve at Montbovon power station in the Gruyère region. It was a meticulous task, brilliantly carried out by the mechanical assembly teams in Martigny.

The Montbovon power station is located downstream of the Rossinière dam in the Gruyère region. Despite its advanced age of 52 years, the Group 2 safety valve had never been overhauled. However, with a diameter of 1800 mm and a nominal pressure of four bars, this valve is a key element in terms of water management and plant safety. The existing hydraulic system operates at high pressure, namely 48 bar. Consequently, regular maintenance is required to ensure the reliability and smooth operation of this head valve

Dismantling, sandblasting, machining, sealing, corrosion protection

Groupe E chose the expertise and know-how of HYDRO’s central workshops for this essential maintenance operation. Work began in September 2023. After dismantling and sandblasting the painted parts, all the components under stress underwent in-depth non-destructive testing. Wear parts were replaced by new ones, designed and machined at our Martigny site. All the seals were replaced with new ones to ensure a perfect seal for the valve. Finally, before reassembly, all the anti-corrosion work was meticulously redone according to procedure.

The pressure tests carried out in December 2023 in the presence of the customer met the latter’s approval.


HYDRO Exploitation SA
Rue de l’Industrie 10
CP 315 - CH-1951 Sion
Contact us
HYDRO Exploitation SA
Rue de l’Industrie 10 CP 750 - CH-1951 Sion +41 (0)27 328 44 11
Send us an email Contact us via the form

Cookie policy

By continuing to browse this site, you agree to the use of cookies to improve your user experience and for the generation of visit statistics.

You can customise the use of cookies using the buttons below.

Accept all Reject all My preferences