Putting Heads Together To Master Chip and Coolant Recovery
Rexnord Corporation's Seal Operation in Wheeling, Illinois, manufactures mechanical shaft seals used in a variety of applications. They are key components, for example, in hydraulic pumps for military and commercial jet aircraft engines, in air conditioning compressor units for buildings of all sizes and in refrigeration units designed for over-the highway trucks.
For efficient machining operations, Rexnord has arranged their 45 machining centers, turning centers and grinders in cellular configurations. Raw materials, which range from aluminum to steel and exotic alloys, are brought to the cells for virtually complete stock-to-finish machining operations. To combat the problems associated with buildups of chips, fines, swarf and coolant contaminants, the plant's maintenance department had turned to shop-type vacuums as a multi-purpose remedy.
According to Mr. Steve Kiefer, Rexnord's Manager of Maintenance and OSHA Compliance, "We use the vacuums to evacuate chips and swarf from hard-to-get-to machining areas of the machine tools and to vacuum out the coolant sumps of each machine. A lot of fines get through the screens at the bottom of the catch basins and fall into the sumps. Contaminated coolant is bad not only for the machine tools, but also for our operators. A clean plant really is synonymous with a healthy plant."
"The variety of vacs we tried," says Mr. Kiefer, "worked in principle, but most had the same setbacks."
Basically, they had single motors with not particularly strong pickup action. Many of the components of these vacuums were plastic, which were attacked and damaged by the various oils and coolant fluids. This problem also applied to the hoses and accessories, such as nozzles and crevice tools. A stock of hoses was required since each vacuum went through about 3 hoses a year. Moreover, metal fines and swarf were getting into and destroying the motors, resulting in downtime and costly motor repair and replacement. The average lifetime of these shop-type industrial vacuums was about 4 months before major service requirements. The process worked, but called for vacuums that could handle Rexnord's tough shop environment. "We knew we were on the right track," says Mr. Kiefer, "now we just had to find the right vacuum."
After reviewing the specs of different brands of heavy-duty vacuums available, the Maintenance Department ordered a model VAC-2 wet/dry industrial vacuum from Goodway Technologies Corp. in Stamford, Connecticut. The trial period for the VAC-2 industrial vacuum was most satisfactory. The 2 2/3 HP of the twin motors provided 198 CFM air displacement for strong chip-removing suction and 83" static water lift for the coolants. A reusable triple inside filter assembly protects the motors, while a sturdy metal deflector plate protects the interior of the unit from the pelting power of suctioned-up chips. An automatic fluid shut-off prevents overflow of coolant and other liquids.
Satisfied that they had their machine tool maintenance answer, Rexnord ordered 5 more VAC-2 industrial vacuums from Goodway and assigned them to strategic locations in the machining cells. One of the units was placed in the coolant recycling room to siphon off hydraulic and way oils during decanting. This procedure, formerly done with a dedicated skimmer unit in about an hour, is completed in only 5 minutes with the VAC-2.
The VAC-2's at Rexnord's Seal Operation in Wheeling, now at 8 units total, have been in constant use for three years. "During this time," according to Mr. Kiefer, "they have required no service and have experienced no downtime. All machine tools are vacuumed thoroughly at an average of 3 times a week. Even the filter bags have not had to be changed, nor have the interiors required flushing. The VAC-2's are simply emptied as needed and allowed to dry until the next use."
On several occasions, Rexnord's maintenance supervisors talked directly to Goodway's sales personnel and engineers to convey ideas for an even better chip handling vacuum. The first result was a much longer stainless steel crevice tool, that allowed the operators to reach far inside the machine tools for easy access to all chip-clinging areas.
These conversations between Rexnord and Goodway soon led to the development of a new, heavy-duty industrial wet/dry vacuum dedicated to the metalworking industry, dubbed the "Chip-Master." Among the many benefit-oriented features is a trap for small fines and swarf and a change in the filter material, that lets air in while keeping oil and coolant mist out to eliminate fungus and mold growth. The new angular hose entry design causes a cyclone effect to "swirl" the entering chips "around and down" into the vacuum's drum with maximum efficiency. The chips go into a large basket that can be lifted out by a hoist, or forklift, equipped with a hook and dumped into a 55-gallon chip barrel. Steel, aluminum and alloy chips are segregated whenever possible to increase scrap value.
The 30-gallon tank of the Chip-Master holds more chips and coolant than a standard VAC-2, with a petcock at the bottom to drain fluids, which go directly to the recycling room. As for the chips, machining operations for the seal components produce "curls" up to 2 1/2" long, up to 5/8" wide and .080" thick.
According to Mr. Kiefer, the Goodway Chip-Master handles these large chips with ease and has proven to be the ideal industrial wet/dry vacuum for all their chip and coolant recovery requirements, in addition to "housekeeping" the floors in and around the machining cells. "This is a good, solid machine," says Mr. Kiefer. "It handles every job we throw at it and seems to be asking for more. It pulls out chips, gulps coolant and cleans machining areas better than any industrial vacuum we've ever seen. This vac is what I'd call a real winner of a workhorse."
On the bottom line, the Chip-Master bears witness to the solutions that can be achieved when manufacturers and their customers listen and work together to satisfy an industry's needs.