European Gate Valves Ltd have completed a number of contracts for the supply of their double flap gate valves for use on roadstone coating plants. These valves have successfully overcome premature wear and performance problems which beset rotary valves previously fitted, and have extended valve MTBF operating life on asphalt plants from an average of only two months to in excess of two years.
The valves are installed on pneumatic conveying systems carrying filler fines from a bag filter to storage silo. Despite rotary valves being specified as abrasion resistant, they have still developed loss of performance within a few weeks. This includes accelerated wear leading to leaks and lower throughput, necessitating costly overhaul and repair with eventual complete valve replacement required.
The abrasive action of the conveyed material on the casing, combined with the wiping action of rotary valves, increases clearance between the rotor and casing. This enlarges leak paths available to the conveying air, bypassing the rotor and compromising performance, with a growing reduction in the volume of material being transported. Plant throughput diminishes with corresponding increasing levels of maintenance and costs. Downtime for valve replacement also affects output production.
The EGV double flap valves successfully eliminates this continuous expensive process of maintenance/replacement/repair because sealing is achieved through the mating of two flat ground surfaces. No rubbing or wiping action is involved, which minimises the potential for moving parts wear. Due to the design, double flap gate valves also offer further savings. Replacement of any wear parts can be easily carried out through access covers, without the valve being disconnected or removed from the process line.
EGV can supply products tailored to suit the particular thermal, abrasion and pressure requirements of specialised applications, including the requirements of gasification, pyrolysis, energy recovery from waste incineration and mineral processing etc.
European Gates Valves Ltd, Ash Street, Bradley, Bilston, Wolverhampton WV14 8UN
Telephone:01902409590 Fax: 01902 409736