Updated: May 24, 2019
1. Gathering Raw Materials – The first procedure in the production line is to gather the raw materials necessary. Polyethylene (PE) is the most common polymer in the world due to its wide range of uses. Depending on the melting point, PE is divided into three difference categories, low, medium, high and ultra-high, depending on the type of industrial applications. It occurs in the following forms high density polyethylene (HDPE), ultra-low-density polyethylene (ULDPE), Linear low-density polyethylene (LLDPE), medium density polyethylene (MDPE), high molecular weight polyethylene (HMWPE), and ultra-high molecular weight polyethylene (UHMWPE). The type of polyethylene we use for our bags is LLDPE.
2. Film Blowing – The second procedure in the production line is the blown film extrusion process. The small plastic pellets are blended then melted at 176°C under controlled conditions until they are molten and pliable. They are then extruded to form a continuous tube of plastic. Using this form of co-extrusion technology, we are able to produce the bags using three layers of polythene film compressed into one layer, a lot of mail bag suppliers only use two; We believe this extra layer is very important to guarantee strength. Whilst the film is still in its molten state, the film is then inflated and stretched to the desired thickness (50-60 microns when we manufacture the grey mailers). After this the film goes through a cooling process before being cut into the desired shape and size.
3. Cutting Bag Process – The next procedure is to cut the film into the desired shape and size. The rolls of film are cut using a heated blade which melts the film on cut resulting in the edges being sealed, this is repeated until all of the rolls of film are cut into the desired size.
4. Packing – Once all the bags have been cut into the according size, they are all packed into packets of 100 units. Once they have been individually packed these packs of 100 need to be placed into cartons/boxes with the size of bag determining the quantity per box. Once this is completed the full boxes are then placed onto pallets ready to be dispatched.