Operation of pipe tractor


Ningbo Fangli Technology Co., Ltd. is a mechanical equipment manufacturer with nearly 30 years’ experiences of plastic pipe extrusion equipment, new environmental protection and new materials equipment. Since its establishment Fangli has been developed based on user’s demands. Through continuous improvement, independent R&D on the core technology and digestion & absorption of advanced technology and other means, we have developed PVC pipe extrusion line, PP-R pipe extrusion line, PE water supply / gas pipe extrusion line, which was recommended by the Chinese Ministry of Construction to replace imported products. We have gained the title of “First-class Brand in Zhejiang Province”.

Single screw extruder shall be selected for the production of Po pipes. Axial slotted barrel is used in the feeding area. The screw length is 30~36d. The screw structure is two-stage deep variable pitch screw. The screw pitch in the feeding section is less than the screw diameter, and the screw pitch in the melting section and homogenizing section is greater than the screw diameter. In order to enhance the mixing effect, some screws have added mixing head elements. This single screw extruder has high output and good plasticity. For example, when a single screw extruder with a screw diameter of 90mm is used, the output can reach more than 600kg. In addition, the PO pipes of filler calcium carbonate, barium sulfate, wood flour and glass fiber generally use a twin-screw extruder.

The production of PVC pipe is basically the same as that of PO pipe. Commonly used is counter conical or parallel twin-screw extruder, dry mixed powder can be directly extruded. Their output has replaced the previous 18D screw from the 10kg/h large-diameter pipe with a small diameter of 1100kg/h, and the length ratio has been replaced from 25D. For example, the output of a twin-screw extruder with a diameter of 90mm can reach more than 300kg.

The function of the pipe haul-off is to provide a certain traction speed and traction force for the shaped cooling pipe, overcome the friction of the shaped device on the pipe, and make the pipe lead into the coiler or turnover table at a constant speed. The tractor is one of the key equipment of the pipeline auxiliary machine. The tractor shall meet the following requirements:

1.      Traction speed can be adjusted infinitely and stably, and constant speed traction can be ensured. Instability of traction speed will cause large and small changes in the pipeline. Traction speed and extrusion speed wall thickness shall be adjusted by adjusting traction speed. The slower the traction speed is, the thicker the pipe wall is. The faster the traction speed is, the thinner the pipe wall is. Selecting the correct traction speed is an effective way to ensure the dimensional qualification rate of products. At present, the designed traction speed can reach 30 m/min.

2.      A certain traction force shall be maintained, and there shall be no push-pull phenomenon, otherwise it will cause ripple defects on the pipe surface. It shall also have sufficient traction force, which will increase with the increase of contact area and sizing pressure. The traction force of small and medium-sized pipelines is generally 100~600N, and that of large pipelines is generally 800~10000N.

3.      The clamping force of the haul-off clamping device shall be able to be adjusted. Pipes of various diameters can be clamped without causing damage and deformation to the pipe surface. At present, there are multi-caterpillar type clamping devices. It consists of 2~12 caterpillars, which are evenly arranged around the pipeline. The caterpillar is embedded with a certain number of rubber and plastic clamping blocks, mostly concave or at a certain angle, to increase the area of radial pressure applied to the pipeline. The adjustment of clamping force is realized by pneumatic, hydraulic or nut mechanism. The larger the pipe diameter, the more caterpillars.

If you need more information, Ningbo Fangli Technology Co., Ltd. welcomes you to contact for a detailed inquiry, we will provide you with professional technical guidance or equipment procurement suggestions.

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