Caterpillar Is Back on the Coatings Prowl

A company doesn’t earn more than $60 billion (yes, with a B) a year in sales by watching the rust grow on its equipment.

 

That’s why for more than 35 years Caterpillar has been developing and applying advanced wear coatings to extend the service life and performance of its machine components, whether new or remanufactured.

 

Now the same Cat custom coatings are available to other equipment manufacturers and users of large industrial equipment, including some new options the company has developed for hard-chrome replacement.

 

The Cat Reman network—short for Cat Remanufacturing—includes turnkey coating and finish marketed by Shermco Industries of Irving, Texas, a provider of testing, repair, maintenance and analysis of rotating apparatus and electrical power distribution systems.

 

“The strength of the Caterpillar research and development capabilities enables us to identify and validate a solution efficiently, and our network of state-of-the-art remanufacturing facilities allows us to apply the solution, all within our organization,” says Tony Zampogna Jr., commercial manager of Industrial Solutions Advanced Wear Coatings for Caterpillar.

 

“The marketing agreement with Shermco leverages their understanding of industrial customers to identify the best opportunities for Caterpillar technical capabilities to solve problems, and in the end to reduce costs for the end user—the same thing we do with Cat heavy equipment,” he says.

 

The metal deposition wear coating processes performed by Caterpillar include laser cladding, twin wire arc spray, high-velocity oxygen fuel (HVOF) thermal spray, plasma transfer arc weld, cold spray and bore spray.

 

 

Part of that process is Cat’s chrome-replacing HVOF coating and finishing technology, a process that applies a flame-sprayed coating to a special steel, creating a very durable and smooth coating without the use of toxic chemicals.

 

Cat calls it Caterpillar Advanced Surface Technology (CAST) and says that before going away from hard-chrome it used more than 52,000 lbs of chromic acid at its Joliet, Ill., assembly plant. The plant also used 14 million gal of water and 1.3 million kW hours of electricity a year, and required more than 12 million gal of water to be treated on site each year. More than 727,000 lbs of solid hazardous waste was generated in the hard-chrome process.

 

Those numbers have been significantly reduced, according to Otto Rajtora with Caterpillar’s Reman division. He says the HVOF process begins with a grit blast of the component to produce a clean, rough surface.

 

A 0.010-inch-thick proprietary alloy powder is sprayed on at high velocity with a combusted oxygen and fuel mixture, followed by a diamond grind to a coating thickness of 0.005 inches. A diamond polish is then used to prepare the final surface to rub against seals, and then it is off to assembly.

 

Rajtora says the HVOF spray includes air, nitrogen and fuel such as propylene, methane and kerosene. Oxygen is added with the HVOF powder flow, and combining the right velocity, temperature and flux results in a dense HVOF coating of about 1,000 Knoop on the hardness test.

 

“The benefits of the HVOF coating is that it has an RC 90 hardness rating, it generates no hazardous waste, has about 200 percent seal life and has superior corrosion resistance,” Rajtora says. He adds that the AST process has reduced hazardous waste at Cat’s Joliet plant by 85 percent.

 

Zampogna says field and lab tests have demonstrated that CAST can extend component life by up to three times that of traditional coatings.

 

“The process is fast and efficient,” he says. “CAST has become the standard coating on a large range of cylinders across the majority of equipment direct from the factory.”

 

Zampogna says last year Cat Reman took back more than 2.2 million end-of-life units and remanufactured more than 161 million lbs of material. Once a returned part arrives at a Reman facility, it is disassembled down to the smallest parts. Each element goes through a cleaning process and is inspected against strict engineering specifications to determine if it can be effectively salvaged. Accepted worn out components are then converted into production-ready material through advanced salvage techniques which use the same rigorous engineering process that goes into new Cat machines.

 

In 2011, Caterpillar announced that it plans to significantly expand its remanufacturing facility in West Fargo, N.D., saying the increased capacity will help meet the strong demand for remanufactured and newly coated drive train components for large off-highway trucks and other mining equipment, including final drives, transmissions, torque convertors and steering clutches.

 

The $50 million investment includes a 225,000-sq-ft addition that will house increased production capacity for high-tech machining and metal additive processes, as well as a state-of-the-art metallurgical lab. The expansion will also increase the facility’s production of new and remanufactured piece parts and advanced wear coatings. It is anticipated Caterpillar will add roughly 250 additional workers over a three-year period, bringing the total workforce to approximately 550 in West Fargo.