New lines of all-American robots, chillers, mold-temperature controllers.

New Lines of All-American Robots, Chillers, Mold-Temperature Controllers

As we reported briefly last month (p. 85), Sterling, Inc. of Milwaukee kept several major announcements quiet until last week's NPE show in Chicago. One was the introduction of its first line of U.S.-designed and built Sterltech parts-removal robots and a new line of sprue pickers; another was the formation of a new Sterlcool division to sell a broad line of process-cooling equipment (Sterling's first); and the third was the first major overhaul in a decade of its workhorse Sterlco line of mold-temperature controllers. Below are more complete details on these new developments.

In addition, Sterling's Ball & Jewell Div. introduced four redesigned granulators, which are covered in the Materials Handling section of our post-show report in this issue.

NEW ROBOTS & PICKERS

Sterling's Sterltech Div. has been associated throughout the 10 years of its existence with injection molding robots from Star Seiki of Japan, which Sterltech first introduced to the U.S. (see PT, Nov. '81, p. 15). So it's a major move for the company to have now replaced that line with its own domestically made robots and a line of sprue pickers made in Taiwan.

(Star Seiki robots, by the way, are now available from the Japanese firm's new U.S. subsidiary, Star Automation, Inc., which is moving this month into a facility in Menomonee Falls, Wis., where it will begin manufacturing Star robots.)

Sterltech's new STR Series robots with low-profile design come in five sizes for horizontal presses of 200 to 1250 tons. Each model is available in two versions, one with pneumatic drive on the strip and vertical axes and electric servo drive on the traverse axis, and one with servo drive on all three axes. Multiple-stop positioning with servo drive facilitates parts delivery to secondary equipment, such as degating systems, weigh scales, hot stampers, or conveyors. Even with pneumatic drive, slow-speed descent at the product drop end of the cycle aids in precise part placement.

All models come with a Sterltech RMC-1000 programmable microprocessor controller, which consists of a free-standing floor console and a hand-held pendant attached to it by a coiled cable. The pendant has a keypad and 80-character, four-line LCD display, that shows I/O status, mode selection, timer and counter data, and diagnostic messages. The latter messages include identification of the fault and the corrective action required. The pendant can be used to "teach" the robot a sequence of motions at slow speed, which the robot can then repeat at full production speed. Operation sequence and setup parameters are saved even if power is shut off.

Other standard features include palletizing function on all-servo models, venturi vacuum with parts detection, parts and sprue grip with detection circuits, low-air-pressure detection, adjustable parts release at either operator or rear side of the machine, quick-disconnect pneumatic and electrical connections for end-of-arm tooling, SPI robot/molding machine interface, and one-yr warranty on robot and controller. Available options include degating, rotating wrist, quick-change tooling, mold-release spraying, insert loading into either mold half, product extraction from either mold half, defective product rejection circuit, and a second vertical arm. Minimum dry-cycle take-out times are 2.3-3.3 sec, depending on model, and minimum overall dry-cycle times are 10-17.5 sec.

The all-servo Model STR-1100S displayed at the show, with 43-in. vertical stroke and designed for 350-500 ton presses, costs around $50,000. (CIRCLE 1)

In addition, Sterltech introduced seven air-driven sprue pickers sized for machines from 25 to 700 tons. Larger models have two-stage cylinders to maintain a low profile. These pickers are said to boast some of the fastest take-out times available: 0.7-1.4 sec dry cycle, depending on model, with overall dry cycles of 3.4-4.4 sec.

Like the traversing robots, the pickers have a hand-held microprocessor programmer with nine selectable standard preset sequences plus "teach" mode, SPI interface, and ability to remove runners to front or rear side of the machine. Other standard features include ability to swing the entire unit out of the way during mold changes, self-lubricating oil-less cylinders, shock absorbers for smooth deceleration, and runner verification self-contained in the gripper jaws. Options include wrist rotation, vacuum generator, vacuum switch verification, and tooling to remove parts and/or runners. Pickers have a one-yr warranty, plus a five-yr warranty on the controller. A small unit starts at around $4800. (CIRCLE 2)

CHILLERS & COOLING TOWERS

In a second major move, Sterling created a new process-cooling division called Sterlcool. Long known for circulating hot-water and oil temperature-control systems, Sterling now also offers a wide range of chillers, cooling towers, and pump-tank systems.

* Portable chillers: These reportedly feature "operator-friendly" microprocessor controls with PID auto-tuning and easy-read fault indicators, accurate to [+ or -] 1 [degree] F; easily removable top and side panels for access to internal components; long-life, hot-gas bypass valve rated for 5 million cycles; overload component protection; optional NEMA 12 or JIC construction; and warranties of one year on the chiller, three years on controls, plus optional four-yr extended compressor warranty. SPI communications protocol is optional.

"Compact" models are available air-cooled with 1,2, or 3 hp (0.7, 1.7, and 2.7 tons capacity), or water-cooled with 2 or 3 hp (1.9 or 3.2 tons, respectively). These have a 15-gal corrosion-resistant plastic reservoir. (CIRCLE 3)

Portable chillers also include six larger air-cooled models from 5 to 25 hp (5-23 tons) and seven water-cooled models from 5 to 30 hp (6-27 tons). These have 40-gal, insulated plastic reservoirs, and pad-mounted "discus"-type compressors. (CIRCLE 4)

* Central chillers: Available in 21 air-cooled models from 15 to 280 tons and 15 water-cooled models from 15 to 160 tons (larger custom models can also be supplied). All are supplied in compact, ready-to-run construction, with cylinder-unloading capability for energy efficiency under reduced-load conditions. (CIRCLE 5)

* Cooling towers: Available in 21 models from 10 to 175 tons, with corrosion-resistant galvanized or reinforced-plastic construction. Towers are preassembled for low-cost installation, and include plastic fill, drift eliminators, and louvers; induced-draft, cross-flow design; and stationary, removable plastic nozzles for balancing water distribution. (CIRCLE 6)

* Pump-tank assemblies: Include six chilled-water versions from 40 to 950 tons and six cooling-tower models of 30-750 tons capacity. All include centrifugal pumps with cast-iron housings, bronze impellers, and mechanical seals; metal reservoirs with epoxy interior lining and enameled exterior; and automatic make-up valves for hands-off level control. (CIRCLE 7)

TEMPERATURE CONTROLLER REDESIGN

The first major redesign in 10 years of its circulating water temperature controllers was also big news from Sterling's Sterlco Div. (Redesign of hot-oil units is in progress.) One key feature is their new "Muscle-Flow" design, which is said to maximize water turbulence for best heat transfer. Less piping, one-third fewer fittings, and vertically machined ports are said to eliminate flow restrictions. The centrifugal "Muscle Pump" has twin casings for easier seal replacement. Panels on three sides and top can be removed for access to internal components.

New controls in microprocessor and analog versions feature large, bright displays for easy reading. Solid-state analog type continuously displays delivery water temperature, while selector switches provide readout in [degrees] F or [degrees] C, high or low heat, setpoint, and return water temperature. Microprocessor version has two-line, backlit LCD display and status indicators, auto calibration sequence on power-up, auto vent sequence, menu-driven prompts, and simultaneous display of set and delivery temperature, with return temperature and [Delta] T displayed at a touch of the keypad.

Sterling is also proud of what it calls "the industry's most advanced electrical protection package." As local electrical codes and OSHA safety standards grow tougher, Sterling says it has gone beyond standard industry practice to protect both operators and the user's plant wiring by isolating possible electrical problems within the Sterlco unit itself. Standard features include UL-recognized components, NEC electrical code conformance, NEMA-1 standard construction (NEMA-12 optional), operator disconnect switch on the outside of the cabinet, heater fusing, transformer primary fusing, motor fuses, grounded control circuit, and environmentally safe contactors. Sterling has also upgraded the previous one-yr warranty to three and seven years on various components. (CIRCLE 8)

PHOTO : STR Series robots (right) have numerous features to increase reliability and versatility.

PHOTO : Among a broad range of sprue pickers, models for larger machines (left) have two-stage cylinders for long reach while maintaining a low profile.

PHOTO : Seven models of water-cooled portable chillers (above) are just a few of the many process-cooling systems from the new Sterlcool Div.

PHOTO : Sterlco water-temperature controllers (right) have been completely redesigned with new controls, fewer parts, and an advanced electrical protection package.