Yichun City polyurethane Thickness of prefabricated insulation directly buried pipe Polyurethane foam thermal insulation material is used as building thermal insulation and waterproof * * * material, and polyurethane hard foam breaks the common fault of traditional building materials with single function - no thermal insulation for waterproof and no waterproof for thermal insulation. Once the waterproof layer leaks, the thermal insulation layer will lose its thermal insulation function. And other Compared with single functional thermal insulation or waterproof materials, polyurethane rigid foam has obvious advantages:
1. The polyurethane rigid foam has the function of one material for multiple purposes, and has many functions such as heat preservation, waterproof, sound insulation, vibration absorption, etc.
2. Thermal insulation performance * * *, which is the thermal insulation material with low thermal conductivity (≤ 0.024) and high thermal resistance among all domestic building materials at present, and the thermal conductivity is only EPS foam polymer benzene Half of the board.
3. The polyurethane rigid foam has a continuous and dense skin and an interconnected wall close to * * *, which has ideal water impermeability. Spraying method is adopted to achieve continuous jointless waterproof and thermal insulation layer, forming a seamless roof and the whole External wall insulation The shell is waterproof and impermeable.
4. Super self-adhesive performance (no intermediate bonding material is required), firm bonding with roof and exterior wall, good wind exposure resistance and negative wind pressure resistance; Overall spraying construction, complete * * * "hot spot" and "cold bridge"; flexible gradual change technology can effectively prevent the waterproof layer from cracking; mechanized operation, automatic batching, uniform quality, fast construction and short cycle.
5. Stable chemical property, long service life, and no pollution to the surrounding environment; It is self extinguishing from the open fire, and only chars without dripping during combustion. The size and shape of the charring layer are basically unchanged, which can effectively block the entry of air, prevent the spread of fire, and have good fire safety performance.
Polyurethane direct burial Thermal insulation pipe It is called "pipe in pipe" or "jacket pipe" for short. It is a composite pipe that uses the excellent adhesion of polyurethane foam to skillfully combine the polyethylene shell or glass fiber reinforced plastic shell, rigid polyurethane foam plastic and steel pipe into a whole structure when foaming. This pipe is recognized as an ideal thermal insulation material at home and abroad due to its good thermal insulation performance, waterproof, anti-corrosion, long service life, simple construction and other advantages over other structures. Our company is responsible for on-site construction for users on the premise of ensuring product quality. Three layers from inside to outside
Front layer: working steel pipe layer. Seamless pipe (GB8163-87), spiral welded pipe (GB9711-88; SY/T5038-92) and straight welded pipe (GB3092-93) are generally selected according to the design and customer requirements. After the steel pipe surface is treated by advanced shot blasting, the steel pipe rust removal grade can reach Sa2 in GB8923-1988 standard, and the surface roughness can reach R=12.5 μ m in GB6060.5-88 standard.
The second layer: polyurethane insulation layer, which is made by injecting the original liquid of rigid polyurethane foam into the cavity formed between the steel pipe and the outer protective layer with a high-pressure foaming machine. It is commonly known as "pipe in pipe foaming process". Its function is waterproof, but insulation, and support the weight of the heating network. When the temperature of the conveying medium is - 50 ℃ - 120 ℃, rigid polyurethane foam is selected as the insulation layer.
The third layer: high-density polyethylene protective layer, prefabricated into a certain wall thickness of black (* * *) plastic pipe, which can be used after corona treatment. Its function is to protect the polyurethane insulation layer from mechanical hard objects, and to protect the anti-corrosion waterproof high-density polyethylene prefabricated directly buried insulation pipe from being damaged by mechanical hard objects. It is suitable for the thermal insulation and cold insulation engineering of transporting various media in the range of - 50 ℃ - 150 ℃. It is widely used in urban central heating, warm room, cold storage, coal mine, oil port, chemical industry and other industries of thermal insulation and cold insulation engineering. However, HDPE has poor weather resistance and low heat resistance than FRP. The heat resistance of HDPE is 60 ℃ - 70 ℃, while that of FRP is 100-120 ℃. Therefore, attention should be paid in application!
Executive standard for polyurethane prefabricated directly buried insulation pipe products 1. European EN2532, CJ/T114-2003 issued by the Ministry of Construction, and SY/T0415-1996 issued by China National Petroleum Corporation
4. Standards for signing agreements with customers
The polyurethane insulation pipe has low foam strength and soft foam, which is caused by the imbalance of the proportion of black and white materials. The proportion of * * * black materials can be appropriate (1:1-1.05). Note that the proportion of black materials should not be too large, otherwise the foam will become brittle and affect the foam performance.
Prefabricated directly buried insulation pipe has become a relatively mature advanced technology in some developed countries. In recent ten years, China's heating pipeline engineering technicians are promoting the domestic pipe network laying technology to a higher level by digesting and absorbing this advanced technology. The practical results of more than ten years have fully proved that the laying method has many advantages compared with the traditional trench and overhead laying. The directly buried thermal insulation pipe is closely combined by the steel pipe conveying the medium, the high-density polyethylene outer sleeve, and the rigid polyurethane foam insulation layer between the steel pipe and the outer sleeve. This is also the polyurethane insulation directly buried pipe in China's heat supply project.