Smoke signals are good for peristaltic technology

A manufacturer of non-toxic smoke generators has opted for peristaltic pumps as the driving technology for a range of its generators that often have to cope with smoke being pumped for up to two hours.

Concept Smoke Systems has developed a bit of a niche market in supplying high specification non-toxic smoke generators into military, industrial and security applications. While the latter demands large quantities of smoke to be 'dumped' quickly in response to an alarm signal, applications such as fire and evacuation training require smoke to be pumped for up to two hours. Trevor Dunnington, technical director at Concept Smoke Systems told Eureka: "For tasks that call for continuous output, peristaltic pumps are preferable to the conventional piston pumps used for security applications. We knew that Watson-Marlow Bredel Pumps had established a reputation as a high quality pump manufacturer and that its products were proving extremely reliable in the field, and this is why we decided to involve the company for our Spirit 900 smoke generator range. "Every product used in the Spirit 900 is rated far higher than normal, explained Dunnington. "This is one of the reasons we now use the 313 peristaltic pump from Watson-Marlow. Its high specification and low maintenance requirements means we have fewer reliability problems in the field." Conventional piston pumps rely on the fluid media running over the pistons to provide cooling, which raises concerns regarding contamination, clogging and compromised product lifespan. However, peristaltic pumps have no valves, seals or glands and so nothing but the tube or hose touches the fluid. This eliminates the risk of the pump contaminating the fluid or vice versa. Maintenance is minimal and the reliability is much higher than conventional piston pumps in comparable applications. The peristaltic pump draws smoke fluid from its integral two-litre reservoir, forcing it into a heat exchanger where it is vapourised. On exiting the heat exchanger, the vapour condenses into a thick, white, non-toxic smoke with a consistently small particle size of between 0.2 and 0.3 microns.