Extra-large blast machine for blast etching aerospace rings
Guyson International, the UK industrial finishing equipment manufacturer, has installed a Guyson Euroblast 2m PF (Pressure Fed) blast system into a division of a leading European aerospace company.
The extra-large blast cabinet is used to deliver a uniform etched key surface on a range of machined circular aluminium rings prior to bonding.
After blast trails performed at the company’s Skipton demonstration centre, a Euroblast 2m PF blast system (2.1m deep x 2.5m wide internal cabinet) was specially designed by their engineering team to provide a side loading and forward tilting turntable which can accommodate rings up to 1.8m diameter and a 20kg load.
The side loading scissor lift design permits the load table rails to be lowered, once the tilting turntable has been manually pushed into the blast chamber, allowing the full height cabinet side door to be tightly closed creating a seal to prevent dust and media escaping during the blast operation.
The external frame also allows components to be loaded outside the cabinet using a crane or hoist where necessary and is fitted with blast media catch trays and hopper to contain and collect any spent media, for a cleaner and safer working environment.
Blast etching of the aluminium rings takes place within the blast chamber, with the tilting turntable allowing the components to be vertically raised directly in front of the operator’s eye line. This enables enhanced parts visibility, easier manual rotation of the turntable and better line-of-sight blast access to the rings.
Internally mounted roof and forward bulkhead lighting, coupled with light coloured rubber curtain lining which provides cabinet protection and good contrast for parts visibility, ensures excellent shadow free visibility through the two operational viewing windows during blasting. Two sets of wide armhole sleeves provide the operator with a choice of operating positions; along with greater flexibility to blast all around the circular components.
A 55-litre capacity pressure pot is used to generate the blast stream within the blast chamber and when the full-width foot pedal (which can be operated by either foot) is depressed it pressurises the pot and starts the blast operation; similarly releasing the pedal de-pressurises the pot and stops the process.
Blast media is fed from the pressure vessel into the cabinet through a heavy-duty hose to the boron carbide blast nozzle. The flow of media is controlled by a manual pinch valve mounted on the cone of the pressure pot; this regulates the volume of media being released into the compressed air stream. After blasting a trigger operated air wash gun removes residual dust and blast media from the rings.
After extracting everything from the bottom of the blast cabinet, the cyclone reclamator, located in the tower above the G55 pressure pot, separates reusable blast media from dust, debris, and undersized media. By drawing the lighter particulates to the dust collection unit and returning the heavier re-usable blast media to the pressure pot, contamination by abraded particles and debris is greatly reduced, thus making the surface finish more consistent.
The whole blast system is completed with a Guyson C800 twin cartridge filter dust collector, a highly efficient unit for filtering out and collecting the dust-laden air from the blast cabinet. The heavier extracted particles being deflected downwards towards the collection bin, the lighter particles are captured on the surface of the filters. Any small pieces of debris removed by blasting are captured by perforated steel floors in the blast cabinets hoppers, thus reducing blockages in the blast hose/blast gun.