Using CAD to optimize molding floor layout

About ten years ago, Brightwell Dispensers of Newhaven, England created an in-house molding division, Ferryfield Moldings, to counteract price increases from suppliers. That decision has worked out well. Ferryfield has grown steadily and finally outgrew its original quarters in Brightwell's main plant. A bit more than a year ago, management decided to find Ferryfield a home of its own. Happily, a nearby facility was found that fit the requirements. That left Brightwell facing a classic problem succinctly described by Managing Director Neale Pybus.

"You need more space because you are busy," he says, "but when you are busy, your senior managers have more than enough to do without taking on the planning of a new facility." Just as obviously, the planning has to be done by those who know the needs of an injection molding business first hand. An architect was needed for the physical work, certainly, but there was a much greater need for someone wise in the ways of parts take-out, material handling, and the real working space needed for chillers, dryers, air and water lines, and so forth. Pybus says, "We were faced with having to spend time moving cardboard cutouts of machines on an architect's drawing and then connecting them with services." It had to be done right the first time, but as noted, everyone was already busy.

Machine Supplier as Architect
Since first taking its molding business in-house, Brightwell has had a strong working relationship with Sandretto and its U.K. Technical Center. All its machines, except for a few that were outside the company's range when acquired, are Sandrettos. Thanks to this close relationship, Brightwell was aware of Sandretto's recently developed, computer-based factory planning system. It seemed like a possible solution, and fortunately, that is just how it worked out. Brightwell/ Ferryfield's managers were able to give their requirements to Sandretto's specialists, and in about a week they were looking at a layout, complete with machines, peripherals, and all services, neatly printed from a CAD file.

Two locations in the new Ferryfield factory were designated for molding machines: one for the three largest machines and a second for the eight smaller units. Between these areas had to be accommodated assembly, packaging, and storage of vehicle loads that leave daily for the nearby Brightwell factory and customer factories elsewhere in the U.K. Though primarily a captive operation, Ferryfield is run according to very strict JIT principles. There is never more than a one-day inventory of molded parts in the plant.

The Ferryfield staff gained considerable experience in positioning molding machines as the previous location became severely cramped. Despite that, Works Manager Richard Tutt recognizes there was a real benefit gained in drawing on Sandretto's CAD facility. "Final machine positioning was completed to within a centimeter of the drawing, together with all the service runs, and it even left us room for future expansion," he says. The task was not a simple fitting job. Substantial refurbishing of the new facility was needed. All but the curtain wall, steelwork, a mezzanine floor, and foundations were removed to make way for a purpose-built factory, which the local authority is now using as a case study in its promotional literature. The old plant's low ceilings meant mold changes required considerable muscle and skill in the use of floor cranes. In the new facility, overhead cranes of 7 and 2 tons span the two molding areas, and there is provision for more. The company Rack Engineering installed a storage system to hold up to 300 molds on a floor area less than 65 by 13 ft. The chilled water system and compressors are out of the way on the mezzanine floor, and an octabin/daybin system handles over 85 percent of the resin consumed.

Plant Design, Product Design, Growth
The design had to account for all molding being automatic. There are robots on the 300-, 500-, and 1000-ton Mega machines in the first area, and gravity is used on the smaller machines in the second area. Conveyors run alongside machines, or under the clamp units of the Series Eight machines, for close machine positioning. Tutt says Ferryfield and Sandretto engineers worked together to optimize the space because, "Between machines we only need work space for setters and engineers; all assembly and packing is done away from the molding area. The CAD system made it possible to install eight molding machines-two 60s, an 85, a 95, a 135, a 250, and two 270s-in an area measuring 46 by 53 ft with space left open for a few more." Some machines have already been added, and a few more large ones will follow.

When Tutt joined Brightwell 10 years ago, it was producing four types of soap dispensers from 12 molds. Brightwell has extended its range of both products and markets. There are now more than 220 active tools producing more than 30 laundry dispensers, a variety of liquid and chemical dosing systems, and soap and towel dispensers well known throughout the U.K. The latter are printed in-house with customer logos. This family-owned company also applied its design and engineering expertise to various internal components, first for hand pumps and more recently for gear trains in its electrically driven pumps. A while ago, Tutt investigated nylon and acetals to replace the metal used by other pump manufacturers. The result: "We now mold and assemble our own pumps. Our success can be measured best by the fact that our designs are being copied."

Tight Moving Schedule, Big Payoff

Brightwell simply could not afford much downtime for moving. Pybus says Tutt and his crew were asked to stop production in the old facility on the final day of May 1998 and to have all machines in the new plant fully back on line by June 15. They started bringing up the machines in the new plant on June 10, and by the target date all 15 machines were running through the company's two day shifts. "Richard and his crew deserve a lot of credit for that job," says Pybus. He refers to the new plant, with its overhead cranes and purpose-specific design, as a dream compared with the old space. Restricted headroom there caused the Mega 1000-ton machine to be equipped with Sandretto's automatic tiebar removal system so large, multi-cavity molds could be used. Tutt notes that although not needed, strictly speaking, at the new shop, the easy removal of the tiebar remains a timesaving benefit.

Brightwell invested more than £1 million ($1.6 million) in the new facility. Thanks to good planning and the use of Sandretto's CAD planning system, it is paying off. Pybus says Ferryfield has doubled its capacity with a small increase in the number of machines. He says the Sandretto CAD system and support definitely saved time, both on the calendar and in terms of their own staff's investment. It is not automatic, nor should anyone expect it to be. "You have to apply your experience to the output," he notes. Both Brightwell and Sandretto expected changes during the process, and there were, but a spirit of cooperation produced a good end result.-Robert Neilley