Brushed DC motors are at the heart of the new Apex2 personal air sampling pumps for providing worker air quality monitoring in hazardous industrial environments.
In a move to reduce the health hazard to workers operating in dusty environments, Casella has launched the new Apex2 range of personal air sampling pumps to monitor personal exposure to dust, fumes and vapours in high risk occupational sectors and to safeguard the future health of workers against serious respiratory disease.
The pumps are used to collect a dust or vapour sample in a working environment and the Apex2 personal pump is a small, robust appliance that an individual wears on the body. It draws air through a filter, or sorbent tube, where the hazardous substances are deposited. The filters, or tubes, are then processed in a lab to determine the levels. An occupational hygienist will be able to calculate the level of exposure to the individual using data from the pump, such as the flow rate and the volume of air drawn through the filter and the amount of hazardous substance from the lab results. Companies can use this data to ensure their workers are operating within the exposure limits for that particular substance.
When choosing a suitable dc motor for the pump, Casella approached 3 companies in the UK and all 3 motors were rigorously tested. After this testing, Casella chose the A-max 22 brushed DC motor from Maxon Motor due to its high efficiency and low current. The efficiency of the motor at a working load means less power is required and, as the pump is battery operated, the battery life is prolonged (>45 hours). This results in extended run time of the product, ie the pump will run for an entire shift without recharging. The low inductance of maxon motors helps mitigate low spark ignition, so they don’t ignite gases or dust, which is vital for some high risk industries which require their equipment to be intrinsically safe. The maxon motor was customised with an extended shaft and an added front bearing.
Aamir Qureshi, Technical Lead Design Engineer, commented “We had used maxon DC motors in our previous sampling pumps, so we had confidence in the products from the start. We have always experienced excellent support from maxon. The company has improved delivery times and speeded up the process to help us with our work on hazardous area certification. Maxon’s service included a strip down and inspection after a set amount of running hours and a comprehensive report was produced. This included photographs of the worn motor components after testing. From this report we are able to estimate how many more running hours were achievable.’
As well as personal exposure monitoring in industries such as pharmaceutical, oil and gas, manufacturing and mining, the Apex2 sampling pump is also used for area and environmental monitoring. For instance, it is incorporated into boundary monitoring equipment for construction and demolition sites or open cast mining, to ensure that the surrounding communities are not affected by the dust created from the sites. There are also applications within asbestos clearance for both personal and area monitoring.