Filtration
Fumes are removed from the laser at varying rates of flow using one or more high-pressure turbines. The contaminated air is drawn through a series of up to three layered filters. These filters capture, absorb or neutralise the contaminants within the air removed from the machine. The resulting clean air is expelled from the filter unit into the room usually at a temperature slightly higher than the ambient room temperature. Over a period of time the filter components require replacement to ensure safe and effective performance. The frequency of replacement depends greatly on the type and volume of contaminants generated by the laser cutting and marking process.
High-end filter devices are capable of measuring and displaying to the user the condition of the filter components, the quality of the air in and the quality of the air out of the system.
The advantages of this system:
- Very little workspace is required to site a filter device.
- Zero installation costs.
- No need to change infrastructure or make holes in walls and roofs.
- Quiet running.
- Aesthetically pleasing.
- Very fine control at low flow rates.
- No smells expelled to atmosphere.
- Can be automatically started and stopped on a job-by-job basis.
- Completely mobile, so the machine can be quickly and easily moved to another location.
- The system can usually operate from a domestic power supply.
The disadvantages of this system:
- Generally, the rate of airflow is only just adequate, which can result in lower productivity and higher laser system maintenance. Filters with higher rates of flow are available but they are generally very expensive to purchase/operate.
- A filter system requires frequent monitoring to ensure safe and effective operation.
- Filter components require regular replacement that can amount to significant running costs over time.
- In case of filter failure the system cannot be used at all until a replacement is acquired.
- There are various different configurations of filter media. If the application varies significantly then more than one configuration of device will be required.
- Supply of replacement parts are limited to the system vendor products only.
- Inappropriate use (using the system knowing that the filters are contaminated/deteriorated) can be hazardous and inappropriate filter changes can result in unnecessary premature filter failures.
- The turbines are usually quite expensive to replace.
- A filter device uses workspace close to the machine which can be a problem where space is tight.
- In work environments where ventilation is restricted the filter device can significantly increase the ambient room temperature.
- Although reasonably quite running, the device does add some noise to the work area.