in Vol. 6 - January Issue - Year 2005
"The Ultimate" in Metal Surface Preparation
Brian Lehane, President of Metal Processing Technologies Corp.
Automotive Drive Line Components Cleaned by the Slurry Blast Process
Heat Treated Fasteners before and after Slurry Blast Cleaning and then after coating
Interview with Brian Lehane, the President of Metal Processing Technologies Corp.
MFN, which is always on the look out to talk to interesting and successful personalities within the industries, had the chance to interview Brian Lehane, the President of Metal Processing Technologies Corp..
(?) MFN: Can you give us a little history on yourself, M.P. Tech. and what they do?
(!) B.L.: The company was founded in 1992 and is an extension of my 25 plus years involvement in the shot blasting and peening industry. Accordingly we design and build metal surface preparation machinery. We have a complete product line of airless shot blast cleaning and shot peening machinery as well as the patented “slurry blast process”. Our systems are usually custom designed, especially in the configuration of the material handling. I believe in offering the customer a complete system including all the necessary material handling equipment to complete a stand-alone work cell or to integrate the machinery into an existing process line.
(?) MFN: What do you mean by the slurry blast process?
(!) B.L.: The slurry blast process is best described as “wet shot blasting”. It utilizes a heated, water based, neutral cleaner solution, combined with abrasive media. The heated abrasive slurry is fed to the cabinet mounted rotary slurry wheels. These slurry wheels mechanically accelerate and discharge a high flow of the abrasive slurry at high velocity, in a controlled pattern, towards the objects being treated. A secondary washing cycle removes residual abrasive from the parts and insures clean de-oiled components with a white metal surface free of scale, oil, rust and most importantly, residual surface contaminants.
(?) MFN: What kinds of cleaning agents and abrasive media are most effective in these slurry machines?
(!) B.L.: The cleaning agents we recommend are water based alkaline cleaners with a low ph of between 9 and 11. Various chemistries are available to treat ferrous metals, aluminums and magnesium. Rust Inhibitors can also be included to protect from oxidation after cleaning. A wide range of abrasives are used including stainless steel shot, grit, cut wire zinc, plastic and fused zirconia beads. Naturally we need a durable media as some of our larger systems are propelling up to 800 kg. per minute of blast media.
(?) MFN: Is this a closed loop process and are you able to classify the abrasive media and re-circulate the alkaline cleaner?
(!) B.L.: In order to be economically viable we had to insure operating costs were reasonable. The systems are closed loop and the spent slurry returns to a hydraulic classifier where it is recycled and separated into the various components. The system recycles the useable media and removes the degraded abrasive and contaminants with the dirty liquid as it flows through the classifier. Various levels of filtration are available to remove these contaminants from the neutral cleaner before recycling to the slurry heads. The accumulated oils are removed by oil skimming devices. A liquid controls package monitors the liquid level, temperature and process flow. Individual valves control liquid flow for either blasting or washing. An important feature is that the system pump only handles liquid and never comes in contact with the abrasive.
(?) MFN: Are there any environmental benefits for slurry blasting as compared to shot blasting or other metal cleaning processes?
(!) B.L.: Yes there are several environmental benefits. First of all no Dust Collector is required, as it is a Dustless cleaning process, so quality of air is improved. In heavy cleaning applications less aggressive chemistry can be used as we rely on the mechanical cleaning action of the media. This is also true in chemical de-scaling where acids are traditionally used and now can be replaced by water based alkaline solutions combined with the abrasive media.
(?) MFN: What are some typical applications and benefits for this process?
(!) B.L.: Well, the applications are only limited by the imagination of the end users, as they are constantly surprising me by new uses for the process. I like to promote this process in any application where a coating or adhesive is to be applied over a metal substrate requiring profiling, de-scaling, de-burring, de-oiling etc. Due to the combined blasting and washing action, the cleaned substrate is free of all surface contaminants and can also be rust inhibited to prevent flash rusting during drying and before coating. The cleaner the base surface, the better the performance of the coating or adhesive. We also have had success in processing magnesium castings, eliminating explosive dust and fire hazards. Automotive re-builders are also very interested in this technology. The use of aluminum is growing more in the automotive industry and will continue to replace cast iron in cylinder heads and engine blocks. New cleaning technologies will be required that can deal with aluminum as burn-off ovens will be become obsolete. We feel we are positioned for this industry.
(?) MFN: Can this equipment replace all shot blasting and washing needs?
(!) B.L.: Technically yes, as the equipment can perform any shot blasting operation or washing operation. However it may not be economically suited for all processes as these multi function machines are more expensive than conventional washers or blasters. But if you consider the cost of buying a washer and a blaster and operating both, there is a considerable benefit in reduced floor space, material handling and operating cost.
(?) MFN: Perhaps you could elaborate on some of M.P. Tech’s other products.
(!) B.L.: Our core technology is in the airless shot blasting and shot peening equipment. Our product mix in this area is 50% custom equipment, 50% standard design. With our standard equipment we have a full range of machinery such as tumble blasters, spinner hanger machines, monorail equipment, wire mesh belt systems and table blasters. Our most recent model is a continuous tumble blast machine complete with an automatic loading system.
(?) MFN: How does the slurry blast equipment fit into M.P. Tech’s other product lines?
(!) B.L.: These products compliment each other very well. As our roots are in shot blasting, both families of equipment share the same rugged build quality and wear components of our shot blasting machinery. For example the same centrifugal, direct drive, blast head is used in both products, although the wet wheels are fitted with some proprietary feed parts. This rugged equipment design is an important factor and differentiates us from light duty hand blast and cabinet type machine builders using blast guns or nozzle type equipment.
(?) MFN: Have you had any help in developing the process?
(!) B.L.: Over the years of developing and testing the equipment, our customers have been one of our greatest resources. Our continuous improvement program means that we solicit feedback from our customers on areas that they feel need review. Focused research is then undertaken to critique the area under review. After review, an action plan is put in place and reviewed with the customer. The customer then decides on the next course of action. We also have some strategic alliances with media suppliers, chemical suppliers and manufacturers of specialty metal coatings. With the technical support of this team we are able to fine tune each process requirement and in some applications specifically configure equipment for dedicated cleaning applications. The correct selection of chemistry is especially important to insure proper de-oiling, rust inhibiting, no discoloration, compatibility with the machine components, foaming issues, and ability to release oils removed by the cleaning process. I guess you could say we truly have had a lot of help in making the educated decisions.
(?) MFN: What new programs and advancements can we expect to hear about in the upcoming year?
(!) B.L.: Well the results of our continuous improvement program and requests for special machine configurations are leading us into some exciting areas. We are most excited about the development of our continuous tumble cleaning system. This will be able to wet blast, wash, rinse, rust inhibit and dry bulk product on a continuous flow basis. Customers have been pushing us in this direction for the last 5 years. This is a very versatile system and will handle individual components such as brake calipers or bulk components such as fasteners. Of course, a full material handling system is offered with this package. Another area we will be concentrating on is enhanced waste water treatment of the alkaline solution. Our goal will be to research, develop and apply new technology that will provide greater environmental protection and subsequently lower operating costs. I look forward to an exciting year for M.P. Tech. and wish to thank all of our customers for their continued support and valued feedback.
(?) MFN: Thank you Brian for taking the time to provide this interview for our readers.
(!) B.L.: Your welcome, thank you very much for considering us for your interview and I hope the MFN Subscribers will benefit in some way from the article.