Polyurethane foam sandwiched plastic steel composite cable duct

Abstract

The invention relates to a polyurethane foam sandwiched plastic steel composite cable duct. The polyurethane foam sandwiched plastic steel composite cable duct comprises an inner duct, wherein an external thread groove is continuously formed in the outer surface of the inner duct along the axial direction of the inner duct, a polyurethane foam layer is arranged in the external thread groove, and a thermo-setting glass steel tube is arranged on the outer surface of the polyurethane foam layer and the outer side of the inner duct. The structure design is reasonable, the external thread groove is filled and leveled up by the polyurethane foam layer to form a bumped three-dimensional stressed surface, then the glass steel tube is arranged on the outer side face of the polyurethane foam layer and the outer side face of the inner duct, and the polyurethane foam layer is light, so that the weight of the whole cable duct is reduced; as the polyurethane foam layer has strong bonding force when bonded with the glass steel, the glass steel tube and the inner duct can be closely combined into one body, the friction force between the inner duct and the glass steel tube is increased greatly, the inner duct and the outer duct can be prevented from slippage; and besides, the surface of the outer duct is in cylindrical smooth arrangement, and the outer duct has uniform thickness and consistent strength, so that the rigidity is enhanced greatly and the service life is prolonged.

Description

Technical field: [0001] The invention relates to a polyurethane foam-plastic-steel composite cable conduit. Background technique: [0002] There are basically two types of pipe materials used for plastic cable protection in the market, one is thermosetting plastics, mainly fiberglass pipes, and the other is thermoplastics, mainly PVC, polyethylene, and polypropylene pipes. The advantages and disadvantages of the pipes of these two types of materials are as follows: [0003] The advantages of FRP cable protection pipes: (1) FRP pipes are light in weight, high in rigidity, and strong in compressive and subsidence resistance; (2) Large in thermal conductivity, especially when cables are operated underground for a long time; (3) Resistance to temperature differences Well, the service life can reach 50 years in the environment of -40℃~-130℃. FRP cable protection pipes are of uneven quality due to defects in the process itself and shoddy manufacturing by unscrupulous manufacture...

AI Technical Summary

Problems solved by technology

Later, after repeated development, the pipes of two different materials were tightly combined into a whole through the intermediate bonding layer. However, in actual research and development, the biggest disadvantage of producing pipes through the intermediate bonding layer is that the bonding force cannot meet the requirements. The required shear force and tear resistance requirements, it is still easy to cause the inner tube and the outer tube to split and slip when the cable is pulled

Later, a method appeared on the market to tightly combine two pipes of different materials into a whole by opening external thread grooves on the outer surface of the inner pipe. Although the inner pipe and the outer pipe can be connected together, if the outer If the pitch of the threaded groove is too small, the anti-slip effect between the inner pipe and the outer pipe will be poor after winding the outer pipe of the inner pipe with the external threaded groove to form a FRP outer pipe. , after the outside of the inner tube with external thread grooves is wound with glass filaments to form a FRP outer tube, the surface of the outer tube is uneven, the thickness is uneven, and the strength of the thinner part of the outer tube is low, which affects the service life of the entire composite cable guide. For the above-mentioned problems, there is a kind of adding quartz sand layer in the external thread groove on the market, and filling the external thread groove through the quartz sand layer, so that the outer surface of the quartz sand layer is flush with the outer surface of the inner pipe, and then the quartz sand layer The outer surface of the layer and the inner pipe is wrapped with a glass steel pipe formed by glass fiber soaked in resin, but this will greatly increase the weight of the entire cable guide and greatly increase the difficulty of pipe laying and installation.

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