Recirculating Loop Application in Synchrotron Particle Accelerator
This application note provides an overview of the successful use of mechanically sealed centrifugal pumps for the recirculation of raw water in a government research application.
THE INDUSTRY
Diamond Light Source is the UK’s national synchrotron science facility. The synchrotron works like a giant microscope, harnessing the power of electrons to produce bright light that scientists can use to study anything from fossils to jet engines to viruses and vaccines.
The machine accelerates electrons to near light speeds so that they give off light 10 billion times brighter than the sun. These bright beams are then directed off into laboratories known as beamlines. Here, scientists use the light to study a vast range of subject matter, from new medicines and treatments for disease to innovative engineering and cutting-edge technology.
Whether it’s fragments of ancient paintings or unknown virus structures, scientists can study samples with a machine that is 10,000 times more powerful than a traditional microscope.
THE APPLICATION
Diamond Light Source is undertaking an improvement project to upgrade the machine to a 4th generation Synchrotron. This upgraded machine will offer the scientific community the opportunity to exploit much brighter photon beams and an increased coherence over a large energy range. The design increases the electron beam energy from 3.0 to 3.5 GeV. As part of this upgrade eight new RF solid state amplifiers are being installed and their associated dummy loads and circulators have a requirement for water cooling.
THE INDUSTRY
Diamond currently has a closed loop raw water system installed which is used primarily in Beamline Hutches and Laboratories as cooling water, and the operating conditions of this system match the cooling water requirements for the associated new components.
To account for the increased duty required in the raw water circuit, Diamond has replaced its previous centrifugal raw water pumps with two new units from Dickow Pumpen, selected and supplied by Michael Smith Engineers.
THE PUMP SOLUTION
Two Dickow NCL i h 125/250 series mechanically sealed centrifugal pumps long coupled to variable speed motors. The centrifugal pump solution is the ideal choice to handle high volume transfer of low viscosity liquid, and the Dickow pumps’ balanced impellers ensure continuous smooth flow without excessive vibrations. This is key, as any vibrations could be transmitted to the Synchrotron and would have a negative impact on the particle accelerator.
The new pumps provide Diamond with a raw water flow rate of up to 105 l/s at a differential head of 63 metres.
To keep disruption to a minimum and continue to provide the facility with raw water, the new pumps ideally had to fit on the existing concrete inertia bases and connect to the existing pipework infrastructure with minimal modifications. To achieve this, the new pumps were specified to run up to 2950 rpm as opposed to the original restriction of 1450 rpm. The pump bodies and impellers are manufactured from stainless steel to maintain the cleanliness of water that Diamond requires.
The two pumps will operate as duty/standby with only one pump running at any one time and the other providing critical backup (pumps are also generator backed to tolerate power outages). ABB inverters have been installed on the 90kW IE4 motors to provide speed control.
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FEATURE |
ADVANTAGE |
BENEFIT |
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Centrifugal technology |
Pulse-free flow |
Continuous flow, low noise, low vibrations |
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Low viscosity handling |
Reduced wear risk for non-lubricating fluids |
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Mechanically sealed |
Cost saving compared to magnetically driven |
Reliable sealing on different operating conditions |
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Compliance with ATEX |
Adheres to all site regulations |
Safety and compliance |
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316 Stainless Steel construction |
Excellent corrosion resistance |
Suitable for use with a wide range of chemistries |
