In many cases, many safety accidents of the prefabricated directly buried thermal insulation materials buried underground are caused by the unsealed exposed parts of the thermal insulation materials during the construction process. Due to the lack of sealing, water enters the insulation layer and damages the insulation structure, leading to the fall off of the external protective layer of the insulation joint, and steel pipe corrosion eventually leads to pipeline leakage and safety accidents. To avoid risks, we need to pay attention to various details during construction. Now Jinan Color Steel Sandwich Panel Factory will explain it to you.
Polyurethane insulation materials must ensure the sealing performance of the pipeline during construction. During joint construction, if water enters the insulation layer from the joint, the water vapor will carbonize the insulation layer during the high-temperature operation of the pipe network. In the joint, the water in the joint will gradually destroy the sealing effect of the external protective layer of the joint. Once the joint seal is broken, external water will enter the insulation layer, causing the insulation layer to continuously carbonize and extend to both sides. The direct contact between underground water and steel pipe will quickly corrode the pipe, thus affecting the service life of insulation materials and the safety of the pipe network.
Special fittings, such as end sleeves and shrink end caps, can be used to seal the exposed locations of blind ends and walls and make them waterproof through the insulation materials of directly buried insulation pipe systems. The corner of the buried pipeline has a great impact on the safety of the pipeline. In the process of pipeline installation, if there is temporary bending, the stress of the pipeline at the corner will change. Before continuing the construction, the design unit shall recalculate and determine the force range, and take corresponding measures.
During winter construction, lower ambient temperature will affect the quality of interface insulation and foaming, so winter construction should be avoided as much as possible. If it is necessary to construct in winter, the surface of the working steel pipe, outer protective pipe and foaming raw material can be heated in advance before foaming at the joint, and then insulation and foaming can be carried out.
If the soaked insulation materials are not removed, the residual water in the insulation layer will evaporate due to the rising temperature of the pipe network during the high-temperature operation of the pipe network, which will lead to the carbonization of the insulation layer and damage of the insulation layer.
The overlapping length of the outer protective layer and both sides of the thermal insulation material shall not be less than 100mm to ensure the strength and tightness of the outer protective layer of the joint. Especially for hot-melt welded joints, the welding area of the outer protective layer shall be completely overlapped with the outer protective tube of the thermal insulation material to ensure the quality and sealing of the fusion welding.
The above are the details that should be paid attention to in the construction of polyurethane thermal insulation materials. I hope it can help you understand the steps and matters that should be paid attention to in such construction projects, and do a good job in the acceptance of each link, so as to obtain reliable quality assurance for the thermal insulation project. If it is helpful, you can come to our website http://www.jnhscg.com Share your experience!