Drinking straw extrusion
The raw material is measured and poured into an extruder that is fitted with a die which produces a hollow tube shape. The resin pellets are dumped in a hopper on one end of the machine and are forced through a long channel by a screw mechanism. As the screw rotates, it moves the resin down the barrel. As the resin travels down the heated channel, it melts and becomes more fluid. By the time the resin reaches the end of the barrel, it is completely melted and can be easily forced out through the opening in the die. The resin exits the die in a long string in the shape of a drinking straw. It is then moved along by a piece of equipment known as a puller which helps maintain the shape of the drinking straw as it is moved through the rest of the manufacturing process. This elongated tube is then given a water bath, which brings us to our next stage of manufacturing.
Drinking straw cool off (chiller)
At this stage the hollow tube shaped resin undergoes a simple water bath. The resin is stretched through the water bath by the puller. The water bath stops the heat conduction process and ensures that the drinking straw will maintain a specified consistency and diameter. The puller plays a big role in this important step as well.
Drinking straw cutting
After being cooled, the long hollow tube can now be cut to make individual drinking straws. The length of each cut can be determined by setting the cutting machine to a certain speed. The slower the cut, the longer the drinking straw; the faster the cut, the shorter the drinking straw. The machine can be dialed in precisely, so as to get the same cut length every time a certain size drinking straw needs to be produced. The machine itself is just a simple cutting knife. The puller (mentioned above), pulls the long hollow tube into the cutting machine through rotating wheels at the set speed and the blade makes continuous cuts. The individual drinking straws then drop into a bin for collection.
Drinking straw wrapping
Not all drinking straws need to be wrapped, but the batches that do will be placed into a wrapping machine. This packaging is widely used for applications where each drinking straw must be kept sanitary. The method of packaging involves loading the finished drinking straws into a supply funnel. At the bottom of the hopper is a wheel with drinking straw receiving grooves cut in it around its outer edge. The drinking straws drop out of the hopper and are picked up one at a time by this rotating wheel. As the wheel rotates, it moves the drinking straws along to a second wheel, which has grooves connecting to a vacuum source. Sheets or packaging material (paper wrap) are moved onto this wheel from a supply roller. The vacuum holds the paper in place while the main wheel feeds the drinking straws on top of the paper. Another layer of paper is guided under the first and the assembly then passes through a sealing roller. The two layers of paper are then crimped together with the application of pressure and sealed. The sealed sheet of drinking straws then travel along the conveyor to a punching region where a die presses down and cuts out the individual drinking straws. The cut pieces then move along a conveyor to a collection area. The individual drinking straws are then bundled together and packed in boxes or pouches for shipping.