Bardons & Oliver’s CNC turning machine simplifies hydraulic cylinder workflow

July 2012 -  One benefit of specializing in hydraulic cylinder manufacturing is the diverse marketplace for the piston-powered product. Whether for construction cranes or earthmoving equipment, original equipment manufacturers need well-built hydraulics for machines requiring mechanical actuation. For these steel cylinders, OEMs turn to HDM Hydraulics LLC, Tonawanda, N.Y.

With access to this huge end-user base, HDM must rely on efficient cylinder tube-processing systems. It currently operates six 2-axis CNC Cylinder Tube Systems made by Bardons & Oliver, Solon, Ohio, two of which the company installed at the end of 2011. Depending on the job, each CNC turning machine can be configured with appropriate tooling to process outer hydraulic cylinders and their accompanying piston rods.

Bill Anderson, vice president of Ligon Industries Hydraulic Cylinder Group, a part of Birmingham, Ala.-based Ligon Industries, an umbrella company encompassing seven hydraulic cylinder companies including HDM, says Bardons & Oliver has supplied the group with machines since 1995. As of May, HDM’s affiliate company, Hydraulic Technologies Inc., Galion, Ohio, has one more on order.

“We’re a strong advocate for their equipment as it plays an important role in our manufacturing and our success,” he says.

Aside from processing both cylinders and rods, the machine’s power-driven live tooling can finish the tubes per specification in one automatic operation. The 12-station turret houses both static and live tooling, which, for example, drills port or bleeder holes for hydraulic fluid, generates spotfaces or chamfer edges for welding on ports and makes slots for ID or OD snap-ring grooves. Loading tables and finished part unloaders free up operators to monitor the next job. Material handling integrated with complete cylinder processing yields a finished part in one step.

Simple workflow

HDM mainly processes cylinders in 1-inch to 5-inch bore sizes. HTI has two Bardons & Oliver CNC turning machines and can accommodate diameters up to 8 inches on the tube machine and 5 inches on the rod machine, says Anderson.

“The equipment and processes are basically the same but HTI’s equipment can accommodate larger diameter material for their applications,” he adds.

The machine systems are massive: Each one is about 60 feet long and about 14 feet wide. The adjacent bar-feed system is approximately 30 feet long to accommodate the tubes and bars. As of May, HDM is expanding its 44,000 square feet of production space to 66,000 square feet.

“They’re well-built, very powerful machines,” says Shawn Meckes, manufacturing engineer at HDM, referring to the 10 horsepower on the live tooling and 40 horsepower to 60 horsepower on the spindle motor.

The streamlined workflow begins with loading bundles of cylinders onto the bar feeder with a crane. HDM primarily uses 1026 DOM steel tubing for the cylinders and occasionally some 6061 aluminum tubing. The tubes arrive in 24-foot lengths then get pushed into the lathe with the bar-feed pusher, according to Meckes. Next, an operator will call up a program on the Fanuc 30i series CNC control.

“We use collet pads and sleeves to accommodate the different diameter materials,” he says. The height of the bar-feed rollers is adjusted hydraulically to feed the material into the machine collet.

The live tooling drills holes for ports and performs other required machining, which can be placed anywhere along the cylinder’s length and in any radial location. After processing, the tube is cleaned before any subsequent processing and assembly.

“Historically, we would take a tube and cut it to length on a saw and then place one end in a lathe to machine that end,” he says. “We would then flip the tube around and machine the other end and then take it over to a machining center to do any milling or drilling operations required.

Once completed, the integrated finished-parts unloader drops off parts instead of requiring an operator to handle them, making the work cycle automatic, says Meckes. The reduction in material handling allows the operators to run other machines and improve productivity.

Live tooling

Bardons & Oliver’s live tooling in its CNC turning machines is focused on processing the tube and performing all necessary machining in one step. Brian Lane, vice president of sales at Bardons & Oliver, says all turning operations, including boring, threading and weld preps, can be completed on tubes. Any drilling and milling required for manifolding or porting also can be done.

“Those things aren’t necessarily turning operations we’d associate with a lathe, so we added live tooling, which then brings features similar to a machining center where they can do secondary operations,” he says. “That eliminates additional handling for the customer.”

The X and Z are the standard travel axes on the lathe. However, each tooling spindle brings its own dimension of travel because the tooling can rotate and be positioned according to the desired function, says Lane. Live tooling gives HDM more flexibility in terms of wrench flats, cross-drilled holes and large ports.

“Folks are always wanting to do something bigger and heavier, and that’s what we try to build these systems for,” Lane says. All of Bardons & Oliver’s machines are built in the United States, he adds.

When HDM runs any of the CNC turning machine’s programs, it typically holds ±0.001-inch tolerance, Meckes says. The tooling’s interchangeability lends itself to the scale and scope of the production at HDM, which runs three shifts five days a week. If needed, each machine could be configured to run the same operation.

Sometimes, operators will run two CNC turning machines or more, depending the job. “In many cases, we have them teamed up with other pieces of equipment,” says Meckes. “Component pieces will be running on the machines next to them.”

If the manufacturer ever has a problem, Meckes says Bardons & Oliver can troubleshoot over the phone. “Their service guys are great,” he says.

From bundle to completed part

Ultimately, HDM derives most of its value from Bardons & Oliver’s cylinder equipment from the ability to take a bundle of material and get a complete part with both tube and rod. “For HDM, basically, we go from raw material to a finished part in one operation,” Lane says. “From raw to finished part, the materials maybe travel 15 feet and they’re ready to go to assembly.”

Linked to that advantage is the reduction in the amount of scheduling and material handling, which is important for productivity.

The larger the part, the more important material flow becomes. When manufacturing smaller parts, operators can handle the tubes easily. Lane says as the bore size increases and the cylinder stroke increases the length of the tube, the fact they come out of that system ready to use without any additional processing or handling in the shop is “really a big deal.”

HDM’s advantages help it meet the needs of its OEM customers, which install hydraulic systems in material handling, forestry, agricultural and snow removal equipment.

“To efficiently process the different cylinder components required, you need to coordinate the scheduling and flow of product. In addition, the manufacturing processes can require significant material handling,” Anderson says. “The opportunity to have equipment that allows us to process in one step a complete tube assembly and rod assembly is of significant value to us as it simplifies the product flow and significantly reduces the material handling.” MM

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