Training in handling compressors
Published: 01 September, 2006
Most industrial operations can take any one of several approaches to overcoming air supply problems. Some contract commercial operations to refill air cylinders owned by the company. Others may buy large storage cylinders then use stored air to do their own recharging.
If you are operating a medium-pressure compressor (2,000 psi to 2,800 psi) can buy a booster pump to convert medium-pressure air to high-pressure air (3,000 psi to 5,000 psi) required to fill cylinders.
If air cylinders are emptied regularly every month for training, maintenance or firefighting operations, there is a clear advantage for a company to purchase its own compressor and recharge its own cyclinders.
Filling your cylinders
Filled either directly from a compressor purification system (a common approach) or from a cascade system - this would normally consist of at least three 300-cubic-foot (8,490-litre) cylinders - air cylinders for open-circuit SCBA are a staple of industry firefighting and preventative maintenance.
The primary use for compressors is for breathing air applications to recharge air cylinders used for fire & rescue and emergency breathing equipment and for diving (SCUBA) requirements.
Other high pressure applications often include seismic research for oil exploration, and various specialised industry applications such as cleaning and maintenance in rigs, pipelines, storage tanks and refineries.
Basic precautions
If you’re training personnel in how to fill cylinders there are two elementary safety precautions you must take:
- ensure that the cylinder is fully charged but not overpressurised;
- ensure that the cylinders are placed in a shielded charging station to prevent injury should the hose or cylinder rupture.
Air cylinders must be filled to 90% of its rated pressure - ones that haven’t must be set aside from the fully charged ones until they have been recharged. Refilling safety precautions and operating instructions should be posted at every fill station, SCBA cylinders should be filled by trained personnel using proper breathing equipment and should be filled only with approved breathing air.
To reduce the amount of heating which can happen during the compression of air during cylinder refilling, cylinders can be filled at a rate of 300 to 600 psi/minute.
Only specially-trained personnel should recharge closed-circuit SCBA cylinders as these systems contain compressed oxygen not compressed air.
Begin at the beginning
The first and most important lessons a trainee can learn is that a complete air supply system is composed of four stages: the compressor itself, a purification system, a cascade (storage) and a charging station.
Trained personnel must be able to confirm that a compressor is working correctly and safely during operation. They must also know how to clean and maintain it - as relief valve failure and even an explosion may result otherwise.
When a reputable supplier installs and starts up a new compressor, they generally also provide on-site training for all personnel who will be operating and maintaining the equipment. The best trainers even award certificates for all who participate.
