The 3M Gummy Glue swiftly provides a strong bond that can be easily broken for attachments.

An operator inserts a stick of the new adhesive into the 3M Polygun LT low-melt applicator, which is plugged into a standard electric system so that its internal coil will heat the material to 265°F to soften it. The operator squeezes the applicator handle to apply the adhesive to the substrate surface. The attachment is placed on the adhesive within 30 seconds or less in order to form an immediate bond between the two substrates.

For example, Hand Pack Inc., a contract packager based in Richfield, N.J., was using a cold latex glue to attach fold-out printed pharmaceutical inserts on pill bottles, before trying the new 3M adhesive, but found that it took too long to dry. "The 3M low-melt glue and Polygun LT applicator help us manage a part of our business more quickly than we could before," said Andy Griffen, owner of Hand Pack.

Another niche application that the new adhesive is filling is the replacement of predispensed glue dots on backing paper used by packagers.

One example is the 47-year-old water treatment plant that serves the city of Bismarck, N.D.

The city's engineering department planned to install a networked automation system to operate the valves that send 26 million gallons of water per day into the plant's filter beds. Engineers decided to use an Allen-Bradley PLC-5, containing a ProSoft 3100-LTQ interface module, to preside over a Limitorque DDC-100 redundant loop network. The network directs Accutronix MX electronic valve actuators, made by Limitorque Corp. of Lynchburg, Va.

Bismarck, N.D., enhanced process control at its water treatment plant by installing Accutronix MX actuators on the plant's filter bed valves.

Charlie Jaszkowiak, superintendent of the Bismarck water treatment plant, said that the new actuators' interface module eliminated the need for a proprietary master control station.

Operators at the Bismarck plant program the Limitorque actuators by touch-screen control panels that replaced bulkier pushbutton cabinets. Every control panel stands adjacent to each filter so that operators are able to change individual actuator parameters, and also view operational data in real time.

Based on the successful performance of the first seven Accutronix MX actuators, the city of Bismarck added 107 more actuators, with plans for more than 150, and a second DDC-100 network to serve new filter beds that will treat an additional 40 million gallons per day.

Quiet Flex previously relied on a drag conveying system to transport phenolic resin adhesive, a material the company used to bind together fiberglass mats in its ductwork. The rotating polyethylene disc and metal pulley in the old conveyor dragged the resin to multiple discharge points arranged along the top of a feed hopper, so that butterfly valves beneath each discharge point would spread the material uniformly across the fiberglass mat, where a spreader was used to distribute the material.

However, the resin tended to stick to the hopper inlet and discharge valves, slowing down the adhesive flow. Worse, the hopper inlet and valves would plug over time, requiring the line to be shut, and workers to clear these points. This increased production costs dramatically at the Houston plant.

Engineers at Spiroflow Systems, which specializes in manufacturing powder conveying, discharging, and filing equipment, tailor-made a materials handling system for the Houston plant consisting of ten Spiroflow Flexible Screw Conveyors attached to a common feeder. Each conveyor contains a flexible spiral, driven by an electric motor to rotate within an encasing tube to carry material forward through the length of the tube.

Spiroflow equipped the carbon steel, 4x4-foot hopper with ten 60-degree inlets spaced separately at the hopper's base to facilitate the material's even distribution. The hopper previously provided a 45-degree angle of repose, which resulted in reduced conveyed material.

In addition to increasing the angle of the inlets, Spiroflow installed two air sweeps that send powerful bursts of air to loosen resin sticking on the inside walls of the hopper.

Mullally Brothers incorporated the hermetic pumps and control valves manufactured by Hansen Technologies Corp. of Burr Ridge, Ill., into the refrigeration system that keeps the bobsled run's icy surface sufficiently cold and smooth.

The sealless Hansen refrigerant pumps prevent ammonia from leaking out of the pipeline that's used at the Lake Placid, N.Y., bobsled run.

The new run contains more than 55 miles of refrigerated piping to serve 20 curves and 490 feet of vertical drop. Several compressors provided a total of 1,900 horsepower needed to recirculate a peak design load of about 900 tons of ammonia through the piping system. The Hansen hermetic pumps have no shaft seal, which enables them to overcome the high internal static pressure of the hillside system and prevent the ammonia from leaking into the atmosphere.

Instead, engineers encased the motor of the centrifugal pumps in a stainless steel pressure envelope. The absence of a shaft seal also minimizes pump maintenance and, because the pump is lubricated by the refrigerant itself, no oil or grease is needed. An integrated Hansen Pump Guardian controller protects the pumps from abnormal conditions and automatically restarts them when conditions return to normal.

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