An Engineering Marvel – Just Spray to Repair Engine Components
Engine manufacturing and repairs has become so advanced that with a fine spray at a low pressure, defective components can be brought back to life within minutes. Not even a hot work, it is just a cold spray at low pressure can heal engine components with long-lasting life.
MTU, a subsidiary of Rolls-Royce, has started using this latest technology of spraying a compound of metal powders to remanufacture the engine components.
The spray treatment consists of:
- A white blasting abrasive powder,
- A grey powder compound of various ductile metals and an oxide ceramic coating,
- A spray gun,
- An air compressor, and
- An extraction system with electrical power is all what you require to heal the engine components and bring them back to life.
The epoxy resin adhesives, when used over the engine components could last for a very short time and the reliability is always a question. Further, it is highly toxic and has obvious health hazards.
With the Low pressure cold spray system, the compound forms a solid layer, which can then be gently machined into the desired shape with more spray possible if need to build up the component.
- The damaged area is first cleaned and roughened using a fine-grain blasting abrasive.
- Then the selected powder, consisting of various ductile metals and an oxide ceramic, is sprayed over the damaged surface.
- The sprayed surface is machined to restore the original shape to suit the geometry, considering the impacts of origination of stress due to improper surface geometry.
“The low-pressure cold spraying process has the potential to replace the bonding techniques used here,” explained Uwe Czerney, design engineer at MTU Reman Technologies in Magdeburg.
The slightly preheated powder impacts the surface at supersonic speed and is compressed into a solid layer by the impact energy said,” Ralf Brandt
“Especially with the reconditioning of used engines and components, our remanufacturing processes in other words, it means we can offer customers quick and high-quality reconditioning of parts,” relates Brandt.
And since all the equipment fits inside a case, it is very portable. So we could carry out repairs on very large components without having to move them several times.”
In the last six months alone MTU has reported that at least 34 crankcases have been repaired using the process in Magdeburg.
Test & Trial:
In the UK, this system was tested for over 6,000 hours on high-speed trains. The repairs done over the crankcase of the engine with surface damage was used as a test to prove the reliability. Till date all of the repaired areas have lasted. This proves the quality improvement in the latest technology where repairs can be done in no time.
The attractive advantage of this method is that the same area could be re-treated virtually any number of times.
The only disadvantage is that this low-pressure cold spray process can only be applied to very limited areas.
Source: MTU Report