Search results
Results from the WOW.Com Content Network
The flat film is then wound on a spool before further processing or shipping. The height of the film line is often 10 times the diameter of the blown tube or more; film lines in excess of 30 meters are possible. Once the film tube is completely cooled, it is taken up by several nip rollers.
A tube of extruded film being blown to expand. A film blowing machine involves one process used to make plastic film. Extruded tubular processing is most often used with polyethylene films but can be used with other polymers. [1] The film may be laminating film, shrink film, agricultural covering film, bags or film for textiles and clothing ...
Blow extrusion of plastic film. The manufacture of plastic film for products such as food packages, shopping bags, and continuous sheeting is achieved using a blown film line. [5] This process is the same as a regular extrusion process up until the die. There are three main types of dies used in this process: annular (or crosshead), spider, and ...
In extrusion blow molding, plastic is melted and extruded into a hollow tube forming a tube like piece of plastic with a hole in one end for compressed gas - known as a parison. The parison is captured by closing it into a cooled metal mold. Air is blown into the parison, inflating it into the shape of the hollow bottle, container, or part ...
Extruded film can be stretched, thinned, or oriented in one or two directions. Blown or tubular process forces air into an extruded ring to expand the film. Flat tenter frames stretch the extruded film before annealing. [3] [4] Calender rolls can be used to form film from hot polymers [5] Solution deposition is another film forming process.
Surface treatment systems are available for virtually any surface format including dimensional objects, sheets and roll goods that are handled in a web format. Corona treatment is a widely used surface treatment method in the plastic film, extrusion, and converting industries. [1]
The notion is important, since the higher the frost line, the more difficult to control the uniformity of the film thickness. For example, a higher frost line due to higher melt temperature and/or lower cooling rate means a longer time to solidify, and a more smooth and transparent film is produced.
Blown: the resin is melted and extruded through an annular die, it is air-cooled. This is a slower process but provides for higher cling quality. Blown film is not a consistent extrusion process, leading to inconsistencies across the film web. The cost of production is also higher due to the quantity that can be produced per hour.