Stainless steel fittings selected for water filter unit

WPL of Waterlooville, Hampshire, is a supplier of waste water treatment, rainwater harvesting and grease management systems. The company has a broad portfolio of products for market areas ranging from the major water utilities down to commercial and domestic systems.

Compliance with the standards and guidelines imposed by the regional water authorities in the UK is essential for WPL. It was while the company's engineers were weighing up the requirements for a new standalone Submerged Aerated Filter unit that they became interested in Sugatsune's specialist hardware in stainless steel.

The HiPAF (High Performance Aerated Filter) is a below-ground wastewater treatment plant that is supplied to major water authorities. Built from GRP, it is a self-contained unit that services small communities of up to 1000PE (Population Equivalent) capacity and biologically treat water to the consent standards set by the Environment Agency.

To conform to the water authorities' health and safety standards, large access covers with a maximum weight of 25kg were specified so that they could be lifted by a sole operator. Furthermore, a safety grid was to be installed to allow visual inspection but prevent personnel from falling through the access hole into the liquor within. The lid and grid had to be lockable in the open position with a positive locking stay - not a lift-to-release device. Handles were also required, but these could not protrude and cause a tripping hazard. Both the lid and the grid had to be securely hinged.

Stainless steel selected

Needless to say all of the fittings had to be resistant to corrosion, hardwearing and low-maintenance. Stainless steel was therefore the clear and obvious choice as a material, so Sugatsune became the supplier of choice due to its wide range of stainless steel stays, catches, latches and hinges, which are used by specialist equipment manufacturers around the world.

The team at WPL managed to exceed the specification and brought the weight of the lid in the final production unit down to only 13kg, and the combined weight with the grid was only 19kg.

Sugatsune's YA-2020R positive locking lid stay is sufficiently strong to only need one component mounted on the right-hand side of the lid, allowing the operator to support the weight of the lid while releasing the lock. It is made of 304 stainless steel and capable of withstanding years of service in a corrosive environment.

The handles chosen for the lids were the HK-100 folding handles, again in 304 stainless steel. These units click into the open or closed position so they can be tucked away to avoid a tripping hazard when not in use, yet they stay extended when required.

Both the lids and grids are secured with LSB-90 stainless steel butt hinges.

WPL was very pleased to be able to meet its targets with a little help from products readily available from the Sugatsune catalogue and website.