Datrex makes safety and survival equipment, including food for emergency ration kits. These are used for marine escape vessels and supplement disrupted supplies during natural disasters.
Responding to rising demand, Datrex began upgrading its food bar packaging line in mid-2011. The line makes bars that provide enough calories and nutrition to sustain one person for three days.
Datrex selected Conflex to design a shrink wrap solution and Shuttleworth to engineer an automated conveyor and wrapper infeed solution.
Higher throughput capability
They maintained the existing wrapper and added a second higher-throughput capability wrapper, integrating two continuous motion form-fill-seal wrappers. The film is able to feed at a higher speed on the newer line.
After the food bars are formed, they are conveyed in single-file through a specialized accumulation conveyor with low back pressure, called Slip-Torque.
An automated diverter feeds a preset number of bars into the slower, original wrapper lane, then feeds a larger quantity of bars into the lane with the faster wrapper.
This cycle is repeated continuously, so each wrapper is fed a proper proportion of food bars relative to the wrappers’ speed.
Virtually eliminates product damage
Slip-Torque allows for precise product placement and virtually eliminates product damage, claims Datrex.
Should the line need to slow or stop, the conveyor can continue to take food bars from the upstream line for a specified period of time instead of stopping the line.
A low-pressure accumulation buffer absorbs production flow irregularities and provides smooth, even motion.
Slip-Torque uses individually-powered rotating roller shafts and loose-fit rollers, which become the conveyor surface, powered by a continuous chain.
The size and weight of the food bars determines the driving force. When the product stops on the conveyor surface, the segmented rollers beneath it also stop.
Conveyors with Slip-Torque have the ability to modulate the speed of different sections of the conveyor via a central control unit.
As food bars move down the line, the rollers at the back end of the conveyor can be moving faster than the ones at the front. The products can be moving at variable speeds on different sections of the conveyor as dictated by throughput requirements.
Shuttleworth’s Servo-SmartFeed technology measures the leading and trailing edges of bars. It then adjusts the product speed to synchronize the release of food bars into the wrapper without stopping the product flow.
The shrinked food bars from both wrappers then exit on separate conveyors utilizing Slip-Torque technology, move through a common shrink tunnel, and are packed, ready for shipping or storage.
Having monitored the performance of the packaging lines since the system was completed last year, Datrex executive vice president, operations Mills declared: “With the installation of the new packaging system we have increased our production capacity by more than 125% compared to what we were previously running.”