Two new developments that pack more machine into less space were among the many innovations on display at the recent 25th annual fall conference of the Association of Rotational Molders (ARM) in Atlanta. The conference also ushered in new laboratory machines and controls enhancements.
Large-part rotomolding in a small space is the concept behind the new High Volume Shuttle (HVS) machine from STP Equipment Inc., Bromptonville, Que. It integrates a linear shuttle with a rocking oven. It also features a mold-handling platform where a mold can be hung on a rotating arm that is mounted on caster wheels. The wheeled frame rolls the arm into the rocking oven, which rises, oscillates and lowers to eject the molding arm. The machine reportedly occupies up to 50% less floor space than a traditional rock-and-roll model.
The oscillating convection oven has three to five independent temperature zones to improve control in molding oversized pieces, such as kayaks, canoes, and large tanks. The available oven space is 18 to 30 ft long and 100 to 150 in. high. PC touchscreen controls permit programming all aspects of the cycle—cooling, oven angles, temperatures, and cart motion. Set-ups can be stored for quick recall. Other features include four internal air- and gas-injection lines per station.
A prototype of a new linear shuttle machine that saves production space while maximizing oven utilization was unveiled by Ernst Reinhardt GmbH of Villingen-Schwenningen, Germany. Typical machines have arms that move from station to station in a circular motion, which takes up space and doesn’t allow for molds with a shorter cooling requirement to move ahead of a mold with a longer cycle. In addition, heating and cooling chambers normally have a roughly cubical design, while the mold rotates in a spherical space. This causes poor utilization (less than 50%) of the chamber volume and changing distance between the mold and heating/air jet as the mold rotates.
The prototype unit features a linear arrangement of mold load/unload station, two cylindrical cooling stations, and a cylindrical heating station. The molds are attached to a spindle and move linearly on a track. Cooling and heating stations are elevated above floor level, so the molds move underneath them. A mold carrier lifts each mold arm into the heating or cooling station. This arrangement allows a mold with a shorter cooling cycle to move to the unload station ahead of a mold that requires longer cooling.
Mold rotation in the elevated heating section is achieved by rotating both the oven and the mold-carrier arm. Drives, gears, and other sensitive components are positioned away from the heat source. The prototype is being tested by rotomolder Rhein-Bonar in Hockenheim, Germany.
Two lab-sized machines aimed at R&D and product development are new from Plastics Consulting Inc., Palm City, Fla. The same firm introduced the industry’s first lab-scale rotomolder (Shuttle CM unit) in 1998. Its new Shuttle R&D and Shuttle PD models are larger but share basic features: a single offset arm that is DC driven with reverse-rotation capability; natural-gas burner capacity of 200,000 or 300,000 BTU/hr; inert-gas injection port; cooling fan capacity up to 700 cfm; water-cooling mist; and CRT controller. The R&D model has a 30-in. max. swing-arm diameter and a max. load of 80 lb, while the PD series has a 42-in. arm diameter and max. load of 160 lb.
Mergers and Partnerships
Ferry Industries Inc., a major supplier of carousel type machines, recently purchased FSP Machinery Co. Inc. of Winkler, Manitoba, which builds rock-and-roll and shuttle machines. The acquisition expands Ferry’s line of shuttle machines to five models in one- or two-arm arrangements, with separate oven and cooling chambers, swing diameters from 60 to 140 in., and weight capacities from 1000 to 4000 lb per arm. Ferry’s rocking-oven line expands to three models that accept mold diameters from 60 to 95 in. and mold lengths of 180 to 264 in. The purchase also gives Ferry a new line of blenders. FSP will be maintained as a separate company headquartered in Canada.
Turbo mixers produced by Caccia Engineering S.p.A in Italy will likely be sold in the U.S. by the Taylor-Stiles Div. of Littleford Day in Florence, Ky., a maker of mixers and blenders. Caccia also builds the Rotaut line of fixed- and independent-arm carousel units with swing diameters from 50 to 217 in. It also makes the Rotobox line of shuttle machines with swing diameters from 90 to 180 in. These machines are sold here by EAP Machinery Systems, Inc., Erie, Pa.
The RotoCure process-control and monitoring software offered on the Rotospeed line of machines from Ferry Industries has been upgraded to a Windows NT format. The new RotoCure 2000 System Manager is now standard on all Rotospeed models. It uses pull-down menus to ease process set-up and storage and to provide detailed process-tracking and trend data. Users can program variable-speed oven and cooling fans, multiple-path internal air flows, arm and mold positioning, and multi-step water delivery at the cooler. The unit can operate with other windows-based programs that monitor mold conditions. It is designed to link to an office computer for remote access of production data. Users can document and analyze machine and shift operation and performance.