Enhancing UF Plant Reliability with GEMÜ – A Success of a Leading UK Water Company

GEMÜ Great Britain helped a leading UK water utility overcome chronic valve failure in its Clean Water sites. By establishing root causes to do with poor seal design, over-specification and inappropriate materials, GEMÜ suggested the use of R480 range butterfly valves. The replacement ensured higher reliability, better corrosion resistance and higher energy efficiency, all backed by GEMÜ's technical support and service.

The Problem

One of the biggest UK water utility companies approached GEMÜ Great Britain to rectify long-standing reliability issues at two of its Clean Water sites. The company's ultrafiltration (UF) plant was being plagued by constant valve failure, leading to costly downtime and production inefficiencies.

Two key problems were noted:

1. Stem seal leakage – Water entry and contamination of the air system were causing actuator failure, leading to costly downtime and health and safety concerns.

2. Valve corrosion – The valves installed corroded very quickly, resulting in process contamination, excessive opening torques and leakage, and all reducing system dependability.

The Investigation

Following in-depth site visits and interviews, GEMÜ discovered several causes for the failures:

The butterfly valves installed employed a single “U” cup seal design that proved ineffective when installed horizontally. This caused stem seal leaks.

The valves had been oversized to 16 bar, although the system was less than 6 bar. This over-specification unnecessarily contributed to actuator size and weight, torque requirements and caused stem stress.

The customer had also noticed a reduction in valve quality because their present supplier had altered the manufacturing process.

Corrosion problems were traced back to inappropriate material choice: a disc with nylon lining and EPDM liner, both inappropriate to the corrosive CIP solution applied on site. The valves were also not WRAS approved, further reducing suitability.

The Solution

To meet these challenges, GEMÜ provided its R480 butterfly valve series, designed to solve the issues experienced on site.

Its robust two-piece body construction provides bubble-tight sealing as per EN 12266-1/P12 and has a leakage rate of A.

Undercutting discs as low as a rating of 6–10 bar reduced actuator weight and size, increasing torque efficiency.

The stainless steel disc with a WRAS-approved EPDM liner gave excellent corrosion protection.

Aerodynamic disc design gave improved Kv values, which helped to reduce energy consumption.

Customer trust was bolstered by previous successful history: a GEMÜ D480 valve installed six years earlier had never leaked nor resulted in downtime, proving the durable longevity of GEMÜ technology compared to that of other products.

Long-Term Partnership

GEMÜ worked intensively with the customer to not only deliver a technical solution but also service and support on a regular basis. The upgrade has facilitated improved UF plant performance at several locations, increasing efficiency and reliability over the long term.

GEMÜ R481 pneumatically operated butterfly valve and the R480 butterfly valve series cutaway.

Customer Testimonial

“Membrane filtration systems are very complex, computer-controlled assets. They must have the upmost integrity to prevent pathogens and chemicals from entering the filtered water. The two main causes of unreliability are high unseating torques and stem seal leaks. Virtually all the approved valves we have used over 25 years of service have had these issues. We have trialled GEMÜ valves for over six years and found them to be the most reliable valve available for this application.” – Membranes Range Manager

Download the datasheet : GEMÜ R480 Victoria Datasheet

Tel: 01925 824044
Email: customer.support@gemu.co.uk
Web: www.gemu.co.uk