Punch tool helps pool component fabricator escape
July 12, 2005
Hayward Pools improves punching of pool heaters using DuraBlade parting tool.
|Hayward Pool Products manufactures heaters and pumps for both inground and above-ground residential and public pools. The 400,000-BTU/hour heater heats a 25,000- to 100,000-gallon pool, according to the company.|
Hayward Pool Products, Elizabeth, N.J., produces all of the metal fabricated components for its swimming pool and spa heaters and pumps in its 60,000-square-foot Nashville, Tenn., facility. The company ships finished goods to two warehouses, one located in the eastern U.S., Clemmons, N.C., and the other located on the West Coast, Pomona, Calif. The company also has a strong presence in the Canadian and European markets.
The 82-year-old company manufactures heaters for both inground and above-ground residential and public pools. The heaters for inground pools have capacities from 150,000 to 400,000 BTU per hour and are about the size of a residential HVAC unit. The 400,000-BTU-per-hour heater heats a 25,000- to 100,000-gallon pool, according to the company.
The 100,000-BTU-per-hour-input induced-draft heaters are designed for above-ground pools and spas. The company also makes a 5.5-kW and a 11-kW spa heater.
The material the company uses to fabricate the equipment ranges from 0.032-inch galvanized steel; to 0.075-in. aluminized steel, as well as black and platinum prepainted. The prepainted material is used to fabricate the outside jacket components of the 100,000-BTU above-ground pool heater and the 5.5- and 11-kW spa heaters (see Handling Prepaintbelow).
The prepainted metal is used on our above-ground pool and spa heaters. We do a lot of nesting, and when the guys knock a part out of a nest, we were seeing a lot of scratches across the part. We had to have our vendor put on a protective, peelable polyurethane coating. We didn't want it so thick that we'd have to change the back clearance. It's just a real thin coating—1 millimeter thick. It adheres just enough so it won't peel off when it's in the punching and bending stages. When they are finished, they will remove the protective coating from the parts, and after that the parts will go straight to the assembly line.
Johnny Jones, Hayward Pool Products
The company runs four turret punch presses and 12 press brakes. "We do a lot of forming here," said Johnny Jones, CNC programmer. "We do outsource a small amount of our jacket work, our extremely high-volume parts, but everything else runs across these machines."
Hayward was having trouble keeping up with the rapidly growing demand for its pool heaters, said Jones. The company was plagued with low production rates, step marks on the metal, and other problems, especially while punching some types of material. "The situation we were having on one of our new machines—we were punching 0.075-inch aluminized, and before we punched an entire sheet, we noticed step marks all along on the part," Jones said. "Say you're drawing a straight line, and someone hits your hand while you're trying to draw—that's what it looked like," he explained.
The heat pumps and heaters sit on the exterior of the pools, so any flaws or marks on the metal are visible. "It looked horrible. We have a pretty stringent QA department; they'd kick it back in a heartbeat."
The step marks adversely affected the downstream operations too. "It's critical that the outside edges of the parts are straight before the parts reach the press brakes. If you've got stairstepped parts, when it comes time to forming them, you're going to get inaccurate parts," Jones said. "You could circumvent the problem by grinding the edges, but who wants to sit there and grind down 1,000 parts?"
Plus, the operators were having to shim the parts, but the shimmed parts would be out of tolerance when they went to another operation, because the steps were in a different place, Jones said. The halted production rates created the need for overtime. "We had a lot of downtime, and our punch rates on certain machines were way down. I'd ask, "How come you punched only 150 sheets last night?' and the operator would tell me, "Well, I had to pull a tool out, load a new one into the housing, put it into the machine. Then I'd have to go over and sharpen another one up.'
"We do a weekly scrap report, and we were going through about $500 in scrap per week. So we were losing dollars in downtime, losing dollars in production, high scrap rates, and working these guys every Saturday—I mean, it was just killing us," Jones said.
At first the company's search for the source of the problem was a little like wandering in the desert. "The first thing we do [when we check for problems] is take out the alignment tool and check out the spatial alignment, but the alignment tool just dropped right in, so we knew the machine was fine," Jones said. "The second thing we do is build a complete assembly, put in a new punch, a new stripper, a new die, slow the machine down, and check the X and Y axis alignment. They were both properly aligned. We then punched some parts and checked again, but it looked like a dull tool, and it was stepping again. We also were having a problem pulling the sheet out of the clamps."
Jones said he called Strippit, the manufacturer of the punching machines, to relay the problems they were having and the steps they had taken to locate the problem. "So the Strippit tech comes out, he looks at the machines, and he does exactly the same things—he checks the punch and die alignment, plus he actually looks at the gears, under the assumption that it could be the actual sun gear—which is the entire upper and lower turret—that is what all of your tools drop into. It was going to be a major overhaul," Jones said.
Jones said that would create major downtime for them, so he wanted to troubleshoot the problem some more. He contacted his local Wilson Tool International® Inc. rep, who suggested he try the company's new parting tool.
Wilson's HP Dura-Blade™ parting tool turned out to be just what Hayward needed to solve its troubles. The parting tool is designed specifically to address the most common problems encountered in parting applications—tool wear and punch tip deflection, according to the manufacturer. The tool is engineered with a replaceable, fully guided blade insert made from the company's patented Ultima™ premium tool steel to extend tool life. The tool assembly uses a close-clearance stripper to provide more support at the tip of the punch. This design eliminates deflection, facilitating a higher level of accuracy.
|The fabricator had difficulty punching an entire sheet of 0.075-in. aluminized steel without wearing out the punch tool.|
Jones ordered a 1/4- by 3-in. tool and ran the same material using the new tool. It punched for a full two shifts without needing sharpening. "I came in the next morning and said, "Hey, how's that tool, what's it look like?' and they said it ran fine. I said, "Hold on, let's run it again.'"
The operators ran it successfully for two weeks straight without sharpening it, even while punching 0.075-in. aluminized. "Still no stepping. No resharpening. Perfect punches. With these Dura-Blade tools, they were banging through this stuff with no problem," Jones said. "So I called up and ordered three more."
Jones said the setup, breakdown, and reassembly of the tool are simple, and that he can do these tasks in about two minutes. "You get your guide assembly, your stripper plate, and your punch insert. First you take your punch insert, put some lubricant on it, and load your insert into the guide assembly. Then you make sure your insert is locked in place. You put on your stripper plate, hold the guide assembly in place, apply the correct amount of torque to it to lock them both in, and that tool is together. There's no shimming whatsoever." The tool is equipped with a quick push-button length adjustment.
The only problems Hayward has now, Jones said, are related to the galling nature of the aluminized steel. Aluminized, or aluminum-coated, steel tends to flake. The flakes tend to adhere to the lubricant and build up between the punch and the stripper cap. "You'll get a little binding between that tool and the stripper, because we do have some tight tolerances. It does tend to dull the tool a little bit faster, because that galling will stick to that punch face and sides. So the only thing we have to do with that particular tooling is pop the stripper plate weekly to clean it."
Jones said he attributes the success of the parting tools, in part, to their fully guided capabilities. "These Strippits, they're highly accurate, and we do a lot of autoindexing, so we assume that when we were indexing these older holders and guides, the machine was indexing the tool, but it was not in the proper alignment, and it would punch regardless. But when we went to these fully guided tool assemblies—it's just unbelievable right now."
"The problems went away, and we're all very happy," Jones said.
Fewer Tools. Jones said he has been able to order fewer punches, and less often. "Usually you order a few tools. Now when I call, I'll say, "I need one punch, one die, one stripper plate.'"
Zero Scrap Rate. Jones said that in their last weekly scrap rate report, the turret operators reported zero scrap. "I would say right now, we might scrap, at the most, about 1,000 per month. We actually consider that pretty high, and that's from a bend out of sequence or a bad press brake setup. But as far as the turrets [are concerned], the only time we might get a scrap part is when they load the wrong tool, not from the actual punching.
"So the scrap rate has gone way down, and tool maintenance has gone way down, because you no longer have to pull a tool out of a machine, sharpen it, fill another one up, and drop it in," Jones said.
Overtime Is Over."We were having to pay more man-hours to make up for lost production time. Now overtime is a thing of the past," Jones said.
Throughput Tripled. Jones said that one way he measures throughput is by the number of blanks that are processed. Before getting the parting tool, the company processed 200 to 275 blanks per night per shift. "Now these guys are pumping between 600 to 700 sheets per night per shift across these four punching machines—three shifts per day, four operators per shift, five days per week. These guys are doing an outstanding job right now," he said.
The company is producing 335 of the inground models per day, four days per week; 125 per day of the above-ground unit, four days per week; and 80 of the 5.5 kW and 11 kW spa units, one day a week. "So we're cranking it out," Jones said, adding that the company is trying to increase throughput rates even more to meet the rising demand.
Jones said demand shows no signs of a slowdown. "It's been a phenomenal year," Jones said.
Hayward is poised to meet the demand. "We've got so many things going on right now. We just launched our heat pump line this year. We'll fabricate the coil end supports for it, and at the end of this year, we'll make the coils for those also. We're going to introduce a new force draft heater, and we're doing a redesign of a complete cabinet assembly, so we're just constantly expanding. We're also looking to add some more machinery to support these new product developments and releases."
Jones added, "As long as the weather stays nice, you build the pools and we'll build the heaters."
Kit and Caboodle
We try to run out parts in kits. The sheets come blanked-to-size. Our largest presized blank would be about 46 inches by 32 inches. Our largest sheet size will run 49.1 by 55 inches—nothing too big. We don't have any loaders at all. Everything is hand-fed into the machine. We don't want anything too big for these guys. We try to keep the sheet size to a minimum.
Hayward Pool Products Inc., 900 Fairmount Ave., Elizabeth, NJ 07207, 908-351-5400, fax 908-351-5675; 2935 Sidco Drive, Nashville, TN 37204, 615-255-3111, firstname.lastname@example.org, www.haywardnet.com
Wilson Tool International® Inc., 12912 Farnham Ave., White Bear Lake, MN 55110, 800-328-9646, fax 800-222-0002, www.wilsontool.com
Strippit Inc., 12975 Clarence Center Road, Akron, NY 14001, 716-542-4511, fax 716-542-5957