Neftekhim equipment supplier is STARLINGER GmbH (Austria). It is a world leading equipment and process supplier for AD*STAR® woven plastic bags, developer of innovative products and new technologies aimed at maximum customer benefit.
The production of woven polypropylene bags begins with manufacturing of oriented flat tapes.
The tapes are produced by processing pelletized polypropylene. An extrusion stretching line is used for this purpose. The line makes it possible to produce strong, high-quality tapes with specified parameters which ultimately determines not only the strength characteristics of the packaging but also its excellent appearance.
The line includes:
- film feed unit;
- cutting unit, hot air oven;
- tape stretching and orientation unit;
- loosening unit;
- tape bobbin winding unit.
In the extruder under the influence of temperature polymer undergoes the stages of melting, mixing with additives, homogenization and molding of the film through a T-die.
Then the tapes pass through the stretching unit, as a result the internal structure of the tape is changed (molecular chains are pulled along one line), the tape acquires the necessary physical and mechanical characteristics and geometrical parameters. The tape becomes oriented.
Next step is producing fabric with circular weaving looms.
A further step of processing the woven fabric is its coating. Coating makes applying a thin layer of melt composite of polypropylene and low density polyethylene to the woven fabric.
Coating serves to strengthen the bag material and seal it, providing the necessary level of air and moisture permeability.
Coating is possible on both sides of the polypropylene sleeve due to a special system of guide rollers and pulleys.
After coating the fabric is printed.
The finished printed coated fabric is transferred to a machine for cutting the bottom of the fabric and its stitching, where a convection line is used to give the fabric a form of a block bottom valve bag.
The final pressing process makes it possible to significantly reduce the overall dimensions of the bags which is very important for storage, transport and handling operations.
Technical and quality control of manufactured products is performed at each stage of production process.