Product Details/PRODUCT DETAILS

characteristic:

1. It refers to a stretching machine used in the production of biaxially oriented films

2. Most stretching machines are only used for horizontal stretching of films, while vertical stretching is first completed by a set of stretching rollers in front. A few machines can simultaneously complete longitudinal and transverse stretching in one step.

3. It is divided into four stages: preheating, stretching, shaping, and cooling.

Process purpose:

1. The main key components are two sets of guide rails, a transmission chain, and many clips fixed in the chain. Two sets of parallel guide rails open at an expansion angle with the centerline in the stretching section, and the angle size is related to the stretching rate. The distance between the two guide rails after expansion and then parallel is the width of the finished film, which depends on the required stretching ratio that varies depending on the material. The clamp clamps the film and guides the tool along the guide rail until the finished film cools down before detaching.

2. During the stretching process, it is required that the clamp has sufficient tension, does not fall off, has self-locking effect, and becomes tighter as pulled. It should run smoothly at a temperature of 100-280 degrees. Clips are divided into two types: self tightening sliding clips and rolling bearing clips

3. The former has a low cost but is not suitable for quick adaptation, and has the disadvantage of lubricating oil contamination. The latter can be used at high speeds without pollution problems, but the cost is high

4. Stretching needs to be carried out at a constant and uniform temperature. The whole machine is placed in a box and heated by hot air circulation to complete both horizontal and vertical stretching at once. The clamp spacing continuously expands during horizontal stretching, which can be achieved by using a folding ruler type scaling mechanism or different pitch screws to achieve vertical stretching for the production of biaxially stretched polypropylene, polyester, and polystyrene films.