COIL AS 1343998 - Caterpillar

Masking Aids
Masking is required to protect critical surfaces and holes from the effects of the grit blasting and thermal spraying. Any type of material that can withstand the effects of either operation is considered a suitable masking material.The mask can be permanent sheet metal or a temporary material. Temporary-type masking materials are:
Hard Rubber
High temperature silicon rubber
High temperature fiber type materials
Several layers of duct or masking tape
Cloths
LiquidsSpray Booths and Rooms
Any thermal spraying process generates some amount of dust and fumes. The arc spray process also generates an extreme amount of noise. The generated noise is above 116 dB.For environmental control and personnel safety, an enclosed soundproof area is appropriate. Dealer Support, Research, and Oerlikon Metco can recommend various dry cartridge exhaust and soundproof rooms to meet your local safety standards and regulations.Rotational/Traverse Equipment
Rotating cylindrical components should be accomplished in a lathe or other dedicated rotational device. An example would be a floor-mounted turntable. The rotational device controls should provide variable rotational settings to relatively high revolutions per minute (RPM) capability. Specially designed rotating systems can withstand the dusty spray environment, yet provide the part rotational requirements.The rotational requirement for specific parts is provided in the individual Arc spray reconditioning procedures documents. The following formulas can be used to calculate either RPM or SFPM (surface feet per minute) for a part.(3.82 * SFPM) / coating area diameter (inches) = RPM0.262 * RPM * coating area diameter (inches) = SFPMFor a traverse motion of the arc spray gun, the following guidelines should be used to apply an even coating deposit:
Flat work (non-rotating): Traverse the arc spray gun at a rate of 15 - 75 cm (0.5 to 2.5 in) per second, making 6.3 mm (0.25 in) gun position increments per pass.
Round/Rotating Work: Traverse the arc spray gun at 6.3 - 12.6 mm (0.25 - 0.50 in) per revolution.Equipment
Illustration 4 g02723954
Smart Arc by Oerlikon Metco
Illustration 5 g03507371
Praxair TAFA 8830 MHU
For the Cat dealer program, dealers will have a choice of using either TAFA 8830 MHU, TAFA 8835 MHU, or Smart Arc by Oerlikon Metco technology.Recommended arc spray operation consists of the following equipment:
3.66 x 3.66 m (12.000 x 12.000 ft) arc spray room
3.05 x 3.05 m (10.000 x 10.000 ft) grit blast room with either portable pressure blaster or blast system with elevator and separation system, storage hopper, and media recovery
Exhaust for grit blast and arc spray rooms
Exhaust hood and ducting
Either Smart Arc by Oerlikon Metco, TAFA 8830 MHU, or TAFA 8835 MHU wire arc technology
Floor installed turntable
Tank wheel positioner
Head stock/tailstock
4AC air cleaner
Recommended safety devices
Recommended consumablesSuccess of arc spray salvage of piece parts is dependent upon the following steps:Pre-machineChamfer edges to a number 2 break [ 0.05mm (0.002 in)] in thickness. Premachining may include machining to make outside/inside diameters concentric.DegreaseAll piece parts must completely grease free to avoid contamination and to prevent bond failure.MaskingUse of metal masks, rubber plugs, tape, or anti-bond shield areas of a component from being grit blasted or arc sprayed.Grit BlastingBlasting is used to prepare the surfaces for the arc