Polyurethane foam insulation pipe
Polyurethane foam insulation pipe is made of high function polyether polyol and polymethyl polyphenyl polyisocyanate through chemical reaction. Polyurethane foam insulation pipe has character of light bulk weight, high strength, heat insulation, sound insulation, flame resistance, coldness resistance, anticorrosion, no water absorption, easy and simple construction etc. It has been popularly used for heat insulation, waterproofing and leakage plugging in the field of petroleum, chemical, electric power, building, transportation, refrigeration and other industries. And it is becoming more and more irreplaceable
Presentation of structure:
The first layer: working steel pipe layer: According to the design and the client requirements, the seamless steel pipe (GB8163-87), spiral steel pipe（GB9711-88;SY/T5038-92) and the ERW steel pipe (GB3092-93) will be the chosen as the base pipe. The de-rusting grade on the surface of the pipe can reach grade Sa2 (GB8923-1988 standard) after the blasting of advanced processing technology. And the surface roughness can reach in R=12.5 micron (GB6060.5-88 standard).
Second layer: polyurethane insulation layer: Rigid polyurethane foam solution will be one time injected into the space between the steel pipe and the outside protection layer by the high pressure foaming machine that is called pipe foaming process. There are three advantages. One is waterproof, other is thermal insulation and the third is to support the net weight. When the transmission medium temperature is between -50 C and 120 C, the rigid polyurethane foam will be the choice as the insulation layer.
The third layer: HDPE protective layer. It is prefabricated into one certain thickness of black or yellow plastic pipe that is used to protect the polyurethane insulation layer from mechanical damage and the other is for waterproof and anticorrosion.
Application: it is widely used to transmit every kinds of the medium in the heat preservation and cold preservation when the temperature is from -50℃ to 150℃. And it is popularly used in heat preservation and cold preservation construction of the urban central heating, heating room, cold storage, coal mine, petroleum port and chemical industry etc.
Advantages and characteristics:
1.Reducing the cost of the project: it is reported by the relevant department the double control pipeline can reduce 25% (using the FRP as the protective layer) and 10% (using the high density polyethylene as the protective layer) of the total cost of the construction.
2.Low heat loss and energy saving: its thermal conductivity is 0.013-0.03kcal / m ·h ·OC, which is much lower than other pipe insulation materials commonly used in the past. The heat preservation effect is increased by 4 ~ 9 times, and the water absorption is very low, about 0.2 kg ·m ~ (2). The reason for the low water absorption is that the closed porosity of polyurethane foam is about 92%, and the thermal conductivity and water absorption are low.
In addition, the insulation layer and the high density polyethylene or glass fiber reinforced plastic (FRP) protective shell with good waterproof performance outside changed the situation of "wet-cotton-padded jacket" in the traditional trench laying heating pipeline. It greatly reduced the overall heat loss of the heating pipe. the heat loss of the heat network is 2% less that the international standard of 10%.
3.Anticorrosion and good insulation, long lifetime. The rigid polyurethane foam insulation layer is tightly bonded to the steel pipe surface which will cut the infiltration of the air and water then it can play a role of anticorrosion. At the same time, its foaming holes are closed and the water absorption is very small. HDPE shell, FRP shell has good anticorrosion, insulation and mechanical properties. The outer skin of the working pipe is difficult to be corrosion by the air and water.
As long as the internal water quality of the pipe is properly treated, the service life can reach more than 50 years, which is 3 or 4 times longer than that of the traditional ground ditch laying and overhead laying.
Less land, faster construction, favorable environmental protection: directly buried heating pipeline insulation does not need to build a huge trench and it only needs to bury the insulation pipe underground, so it greatly reduces the construction of land.
The amount of earthwork excavation is reduced by more than 50%, and the amount of masonry and concrete is reduced by 90%. At the same time, the heat preservation pipe is processed parallel to the field trench, and the construction period can be shortened by more than 50% if only the spot joint is required.