Category Archives: Case Studies

Prison Complex in Middlesex

Background : The site had experienced multiple failures on the outgoing boosted pipework to the fire hydrant system causing major loss of water and loss of the fire hose-reel system to the prison.

Issues : On investigation it was found that the flexible pipework connector was operating at the limit of its pressure rating and had been installed in such a way as to cause the connector to rub against a raised edge on the PVC flange and cause premature failure of the connector. A temporary repair was carried out to enable the system to operate.

Solution : With the assistance of a specialist manufacturer we specified and installed a custom designed, 25.0 Bar rated, stainless steel flexible connector and also replaced a 2.5m length of PVC-U pipework with 25.0 Bar rated stainless steel. The new pipework was reinsulated and trace heating refitted to match the existing pipework.

London Borough of Redbridge – Fullwell Cross Leisure Centre, Ilford

Customer approached Acorn to advise on solution of underground water course running in leisure centre main boiler plant room. Following site meeting below works were agreed:-

Employed vacuum tanker/jetter unit to remain onsite throughout duration of works to empty pump chamber & keep level down to minimum whilst works are being carried out.
Confined space man entry into well to clean out main side of pump chamber.
Removed 5 bucket loads of silt/debris.
Drilled pump stools to base of chamber.
Cut out & removed existing pumps & pipework/non-return valves.
Installed new pipework & non-return valve.
Connected to existing external pipework.
Measured & cut guiderails, secured.
Installed 2no. new submersible pumps.
Supplied & installed 4no. new float switches & set levels accordingly.
Installed & connected new upgraded control panel.
Setup & commissioned unit into system.
Alleviating flood issues & protecting new boiler installation.

Rain Water Harvesting For Salisbury Cathedral

Aquatech Pressmain supply rain water harvesting system for the new visitors centre “Little Paradise” at Salisbury Cathedral.

Little Paradise is first permanent new build at Salisbury Cathedral since the fifteenth century. A purpose designed building providing new toilet facilities supplied via the rain water harvesting unit, it marks a significant milestone for the cathedral as it looks to deliver a long term programme of improved facilities for its congregation and visitors to the Cathedral and surrounding Close.

The building combines timber, glass and stone to blend perfectly with the historic environment around it, and has minimal impact on the fabric. It replaces temporary toilets, enhancing the appearance of the south side of the building and simultaneously returning the south cloister, which had become an over-flow storage area, to its original beautiful and reflective space. The project has been made possible through donations, legacies and pledges from the Friends of Salisbury Cathedral and other generous supporters.

Portman Mews pump station

This pump station is a foul water facility located in the basement. The well had alarmed over the previous weekend in a highly contaminated state with massive amounts of accumulated fat which had solidified onto the control floats and thus made them too heavy to tip.

The floats were cleaned of fat and returned to the well. Standard checks for fully auto operation were carried out together with load checks’ all parameters and operations found to be normal. The fat accumulation in this well was a direct consequence of the effluent containing a large volume of waste from a restaurant located in the building. The cooking style relies greatly on a product that is essentially clarified butter and the residues from the cooking utensils, plates etc. will find their way into the waste stream regardless of any recycling mechanisms that the restaurant uses for waste oil.

The well required jet washed and then emptying by vacuum tanker. This operation would then need to be carried out at a regular frequency to keep the condition of the well in an acceptable condition.

Office Building – Stevenage LTHW Expansion Vessel

We were called to investigate a repeated history of expansion vessel diaphragm failures. An Ultrasound examination of the vessel thickness revealed thinning of the metal and a subsequent internal examination showed severe corrosion with a sharp edge puncturing the diaphragm. The thinning of the vessel represented a risk of vessel failure and the safe option was to replace the vessel.

Office Block – London Cold water booster set

The hydro-pneumatic accumulator fitted on a cold water booster set in a roof top failed due to hydraulic shock caused by a lack of regular maintenance. The fact that the vessel failed was bad enough but the ensuing flooding of the top two floors caused £1000’s of damage. Routine regular maintenance would have avoided this situation.

166 apartments in Manchester

Flow meter readings were obtained from a block of 166 apartments which measured a peak demand of 2.0 litres per second. National guides widely used in the industry calculated a duty flow requirement of 30.0 litres per second, over sizing the pump set by fifteen times! Subsequently over sizing the delivery pipe work system and electrical supply.

The energy consumption of the original 3 pump fixed speed booster set over a one week period was 924kWh. The pump set was replaced with a 5 pump variable speed booster set with each pump being much smaller than the original fixed speed pumps used. Power consumption over a week for the new pump set was reduced to 134kWh, a saving of 790kWh per week of wasted energy! This equates to a saving of over 18 tonnes of CO2 per annum, and saving £3,000 per year on the electricity bill.

Acorn completed a £128,000 contract for a University on Merseyside

install-case-2-1b — AquaTech Pressmain HY9 variable speed booster set

Acorn completed a £128,000 contract for a University on Merseyside. The project involved the installation of a bespoke AquaTech Pressmain HY9 variable speed booster set.

As well as supplying the HY9AV, an 8” ABS ring main (approx. 100m of pipe was installed, much of it at high level) around the Hydraulics Laboratory with various ‘take offs’ to run a selection ofexperiments where the movement of water is required. These vary from powering both Francisand Pelton turbines, to supplying water to experiments where wave patterns are used to create an ‘hydraulic jump’ to simulate the effects of a tsunami.

The work was completed over a ten week period, with commissioning taking place at the end of the project.

The Tate & Lyle Estate – East London

After – Aquatech Pressmain HY3AV Variable speed booster Set

Acorn was called to the Tate & Lyle Estate in East London after their incumbent pump maintenance contractor failed to solve or respond to an emergency situation on a Pullen Hydropak water booster set. The water booster set had a catalogue of faults including burnt out and leaking pumps, a failed and leaking accumulator and non functioning controls.

The unit was also over sized for the application and beyond economical repair. As the estate had no water a temporary supply was connected, whilst a new Aquatech Pressmain HY3AV 10-6 booster was built and then installed just seven days from receipt of an order, normally this would take 4 or 5 weeks.