Aviaservices, a specialist maintenance, repair and overhaul company approved by the European Aviation Safety Agency, has upgraded its facilities with the installation of a self-contained Hodge Clemco blast-room with integral abrasive recovery and dust extraction systems.

The blast-room has been located in the wheel shop at the 9000m² premises, which has the capability to maintain almost any type of wheel assembly on current aircraft. The main work-load at present involves maintenance, repair and overhaul of Boeing 737, 747, 757 and 767 and Airbus A300 and A310 wheel assemblies. Wheels can be up to 43cm wide x 70cm diameter.

At the Aviaservices facility wheel assemblies are stripped and the wheels themselves are NDT-inspected and repaired in accordance with the manufacturers’ maintenance manuals. When the wheels are overhauled, they are re-painted, which requires the existing finish to be removed and the surface prepared. This work was previously carried out by the use of a hot acid bath and wet-blasting, which was a slow process and involved the use of hazardous materials that required special handling and disposal.

Surface preparation is now carried out in the containerised Hodge Clemco blast-room, which has an ATEX-approved dust collector attached to the rear, providing a completely integrated unit that can be moved in a single operation, if required. This design has provided good access to the dust collector for maintenance and easy disposal of waste media, while maintaining a blast-room floor area measuring 2.4 metres wide x 3.7 metres long. The design also allows reverse-pulse cartridges to be used on the dust collectors, which are more convenient and efficient than conventional dust bags.

Plastic media suitable for the aluminium wheels is projected by a 2040 SGV blasting machine via a 5/16in. (8mm) ID silicon-carbide-lined nozzle fed from an external abrasive storage hopper. The blasting system includes a fail-safe dead-man’s handle, water separator/air filter and convenient dial-type air pressure regulator.

Abrasive is recovered by means of a sweep-in hopper in the floor of the blast-room linked to a storage hopper mounted above the blast machine via a cleaning system that separates dust and large particles from re-usable media. Large particles are screened out by a sieve, while dust is drawn into a pleated cartridge that is cleaned by an intermittent pulse of air. Dust drops into a removable bin, while re-usable abrasive passes into the storage hopper, which automatically re-fills the blast machine.

The ventilation and dust-extraction system provides the equivalent of 2.5 air changes per minute, ensuring good visibility for the operator. A pair of protective gauntlets and a viewing window fitted to one side of the blast-room allow operators to work outside the chamber, so they do not need breathing apparatus or protective clothing.