Supply of direct buried insulation pipes in Tianjin

Supply of direct buried insulation pipes in Tianjin

Polyethylene outer protective pipe polyurethane prefabricated buried insulation pipe has excellent overall performance. The product strictly follows the CJ/T114-2000 (EN253:2009) standard. The working steel pipe adopts the process of shot blasting rust removal on the outer surface and corona treatment on the inner surface of the outer protective pipe to ensure the three in one performance of the insulation pipe. The service life is as long as 30-50 years, with strong stability and extremely low maintenance costs. The insulation effect is 4 to 9 times higher than other insulation pipes, and the heat loss is only 25% of traditional pipes. Under normal circumstances, it can withstand temperatures of 120 ℃, and the highest peak value can reach 150 ℃. Outer protective tube density ≥ 940kg/m ³, tensile strength ≥ 20Mpa; Thermal insulation foam density ≥ 60kg/m ³, compression strength ≥ 300Kpa, thermal conductivity ≤ 0.03w (m.k), closed cell rate ≥ 90%.

Supply of direct buried insulation pipes in Tianjincharacteristic

(1) Convenient production and reduced engineering cost

(2) Excellent insulation effect, energy-saving and environmentally friendly

(3) Long service life and low maintenance costs

(4) Easy construction, reducing environmental damage

Directly buried insulation pipeStructure:

(1) Working steel pipes: According to the technical requirements of the conveying medium, seamless steel pipes, double-sided submerged arc spiral welded steel pipes are used.

(2) Thermal insulation layer: rigid polyurethane foam.

(3) Protective shell: Made of high-density polyethylene or fiberglass.

(4) Leakage alarm line: When manufacturing high-temperature prefabricated buried insulation pipes, an alarm line is buried in the insulation layer near the steel pipe. Once a leakage occurs in a certain part of the pipeline, the transmission of the alarm line can trigger an alarm on the detection instrument and display the section of the pipe that quickly handles the leakage, ensuring the safe operation of the heating network. The accurate location and degree of leakage of water, in order to notify maintenance personnel quickly

Safety of prefabricated buried insulation pipes

The high-temperature prefabricated buried insulation pipe designed and produced by Tianjin Haimen Building Materials Co., Ltd. can be equipped with a leakage alarm line according to requirements. Once a leakage occurs in a certain part of the pipeline, the accurate location and degree of leakage of the insulation pipe can be displayed on the detection instrument through the transmission of the alarm line, so as to notify the leakage personnel to quickly deal with the leaking pipe section and ensure the safe operation of the heating pipe network.

The properties of prefabricated buried insulation pipes

High temperature prefabricated buried insulation pipes not only have the technical and practical performance of traditional trench and overhead pipeline laying, but also have significant social and economic benefits, and are also powerful measures for heating energy conservation.

▲ Steel sleeve steel steam insulation pipe

Classification of steel insulated pipes with steel sleeves

Prefabricated steam insulation pipes can be divided into two types of structures: internal sliding and external sliding.

Internal sliding buried steam insulation pipe

Internally sliding buried steam insulation pipe, the insulation material and outer protective pipe remain relatively stationary, mainly due to the thermal expansion of the working steel pipe moving within the insulation material. This structure is suitable for hard insulation materials. The advantage is that there is no need to set a support ring between the working steel pipe and the outer protective pipe, and the inner wall of the outer protective pipe is not easily corroded. However, the disadvantage is that it can easily cause eccentricity and crushing of the insulation material.

External sliding steel sleeve steel insulation pipe

The external sliding steel sleeve steel insulation pipe has a sliding surface on the inner surface of the outer protective pipe, and the insulation material moves together with the working steel pipe. This structure is suitable for soft insulation materials, and its advantages are to ensure that heat flow does not leak out, solve the problem of increased friction caused by radial expansion, and have support rings inside, which will not cause eccentricity or crushing of the insulation material. According to the design and requirements, the outer protective layer of the steel insulated pipe can be treated with three-layer PE, epoxy coal tar or fiberglass anti-corrosion technology measures to prevent steel pipe corrosion.

Steel sleeve steel steam insulation pipe structure:

The prefabricated buried insulation pipe consists of several parts, including working steel pipe, calcium silicate, reflective layer, fastening steel strip, sliding bracket, glass wool, air layer, outer protective steel pipe, and wrapped fiberglass.

(1) All inorganic materials, non combustible, and do not decompose toxic gases.

(2) Easy to process, sawing and cutting, convenient on-site construction, and low loss.

(3) The aqueous solution is neutral or weakly alkaline and will not corrode pipelines and equipment.

▲ Polyethylene outer protective pipe

The density of the polyethylene outer protective tube is ≥ 940kg/m ³, the tensile strength is ≥ 20Mpa, the carbon black content is 2.5% ± 0.5% (mass percentage), and the difference in melt flow rate between the two tubes is not more than 0.5g/10min. Cut both ends of the pipe flat, with an angle error of ≤ 2.5 ° perpendicular to the axis.

▲ Directly buried insulation pipe fittings

Directly buried insulation pipe fittings meet the CJ/T 155-2001 standard, and their product scope of application is equivalent to the standard requirements for prefabricated directly buried insulation pipes in CJ/T 114-2000. Insulated pipe fittings include prefabricated insulated elbows, insulated tees, insulated variable diameter pipes, fixed joints, and insulated joints.

▲ Steel sleeve steel insulation pipe fittings

The technical process requirements for steel sleeve steel insulation pipe fittings basically meet the technical requirements for steel sleeve steel insulation pipes. Meets the CJ/T 155-2001 standard, and its product scope of application is equivalent to the standard requirements for prefabricated buried insulation pipes in CJ/T 114-2000.

▲ Fiberglass lined steel insulated pipe fittings

The technical process requirements for steel sleeve steel insulation pipe fittings basically meet the technical requirements for steel sleeve steel insulation pipes. Meets the CJ/T 155-2001 standard, and its product scope of application is equivalent to the standard requirements for prefabricated buried insulation pipes in CJ/T 114-2000.

▲ On site patching of buried pipes

The direct buried pipe patching process is divided into wrapping method, hot melt sleeve method, and sleeve method for on-site patching construction. For detailed processes, please refer to the Haimen direct buried pipe patching process flow.

Direct buried pipe joint filling and wrapping method

(1) Take a thermoplastic strip (usually 50mm wide) and place one end parallel to the weld seam, with a width of * on both sides.

(2) Use a welding gun or spray gun to heat the joint between the weld and the thermoplastic tape until the insulation plastic shell begins to melt at the joint with the thermoplastic tape. Then quickly apply pressure to the insulation pipe on the surface of the thermoplastic tape by hand until the adhesive is squeezed out of the thermoplastic tape section. Perform circular operations in sequence until reaching the starting point, and then cut off the thermoplastic tape at a 50mm overlap with the starting point to check the hot melt condition. If there is any loose contact, use a plastic welding gun to heat the surface of the thermoplastic tape and apply pressure by hand until the adhesive is squeezed out.

Hot melt sleeve method for directly buried pipe joint repair

(1) Break off the throw away hot-melt sleeve and wrap it on the insulation pipe jacket at the bare pipe interface. The width of both ends of the jacket and the axial overlap should be more than 50 mm. The section of the outer jacket should be neat. The middle of the overlap with the outer jacket and the lower part of the axial overlap of the sleeve pipe should be insulated with Flat noodles pads. The wiring terminals about 50 mm exposed at both ends of the wire mesh should be fastened with clamps. The cross-section of the outer sheath should be neat, and the joint between the joint and the insulation jacket should be tightly pressed in a circular shape with packing tape. Use a wooden hammer to lightly tap and tighten while tapping, and tightly bond with the plastic on both sides.

(2) Connect the two end wire interfaces of the heating wire mesh to the power output terminal of the electric fusion machine, adjust the fusion machine according to the set fusion time and current, and heat it until the plastic shell of the insulation pipe melts and overflows at the joint with the hot melt sleeve. The fusion machine will automatically power off and the fusion is completed.

Directly buried pipe patching sleeve method

First, move one side of the insulation pipe sleeve to the welded bare pipe position, and the overlap length with the insulation outer pipes at both ends should be greater than 50 mm. 2) Use a plastic welding gun to weld the cross-section of the sleeve at both ends and the insulation pipe shell in a circular shape, and it is qualified if the welding rod cannot be torn off.

Directly buried steam insulation pipe joint repair

1. The structure at the interface of steam buried insulation pipes should be the same as that of the straight pipe section of the pipeline network.

2. The laying of insulation layers is of composite type, among which the main insulation layer can be divided into high temperature and ordinary types according to the model. The joint ends are all equipped with staggered joints. Before placement, the filling material of the staggered joints should be removed and placed in layers. The wrapping should be smooth and full, tightly tied with packing tape, and covered with an aluminum foil anti heat layer.

3. When the outer sheath of the insulation pipe is a steel jacket, the outer pipe interface needs to be welded. After covering the insulation material, the outer steel jacket is cut into two semi-circular tiles, and the groove is welded firmly to the outer steel jacket of the straight pipe section.

4. Remove welding slag, welding flux coating, and burnt anti-corrosion residue on the outer steel sleeve of the insulation pipe. Perform external anti-corrosion treatment on the interface and welds according to the anti-corrosion requirements of the steel sleeve outside the buried pipe.

5. Keep records of concealed works.

Tianjin Haimen Building Materials Co., Ltd. was founded in 1987, formerly known as Tianjin Haimen Thermal Insulation Material Factory, which was originally a military enterprise. The company is located in the Marine Development Zone of Binhai New Area, Tianjin, and the registered trademark for its products is the "Haimen" brand. The company mainly produces prefabricated buried insulation pipes, polyurethane buried insulation pipes, high-density low-pressure polyethylene outer protective pipes, buried insulation pipe fittings, steel sheathed steam buried insulation pipes, fiberglass sheathed steel insulation pipes, and steel sheathed steel insulation pipe fittings; Rock wool products, glass wool products, ceramic wool products, silicates, high-temperature insulation blankets and other insulation materials, as well as pipeline and tank insulation engineering, anti-corrosion and rust removal engineering, etc. The company has obtained ISO9001 quality management system certificate, ISO14000 environmental management system certificate, ISO18000 safety management system certificate, and other honorary certificates. The direct buried pipe products not only meet national standards, but also meet * standard requirements; Mineral wool products have obtained certifications from EC, ABS, GL, LR, BV, NK, CCS classification societies, and meet the A-60 fire resistance rating.