Characteristics of glass steel pipe

1. and has good corrosion resistance. Because the main components of FRP air duct are composed of polymer unsaturated polyester resin and glass fiber, it can effectively resist the corrosion of acid and alkali such as acid, alkali and salt, and the corrosion of untreated domestic sewage, corrosive soil, chemical wastewater and various chemical liquids, so it can generally maintain the safe operation of the pipe network for a long time.

2. Good aging resistance and heat resistance. Glass fiber reinforced plastic pipes can work normally for a long time in the temperature range of -40℃ ~ 70℃, and can also work normally above 200℃ with special high temperature resistant resin. Long-term outdoor use of pipes with ultraviolet absorbent on the outer surface can eliminate ultraviolet radiation to pipes and delay the aging of FRP pipes.

3. Good antifouling performance. When the temperature is below-20℃, the pipeline will not crack after freezing.

4. Light weight, high strength and convenient transportation. FRP pipes are not only light in weight, high in strength and strong in plasticity, but also convenient to install and transport, and it is also easy to install various branch pipes, and the installation process of sliding doors is simple.

5. The hydraulic conditions are well chosen. The inner wall is smooth, with strong conveying technical ability, no scaling, no rust and small water resistance.

6. Good design. According to the specific needs of consumers, such as different flows, different pressures, different burial depths and different loads, the different grades of materials can be clearly identified, and the same materials also have grades.

7. Good wear resistance. Water containing a lot of mud and cement sand was put into the pipeline, and the comparative experiment on the influence of rotary wear was carried out. After 3 million revolutions, the wear depth of the bottom of the inner wall of the inspection pipe is: the steel pipe coated with tar and enamel is 0.53mm, the steel pipe bracket coated with epoxy resin mortar is 0.52mm, and the steel pipe bracket with surface hardening treatment is 0.21mm. Therefore, FRP has good wear resistance.

2 Standard dimensions and specifications of glass steel pipes

Diameter deviation: the outer diameter grade shall conform to the provisions of Table 1, and the inner diameter grade shall conform to the provisions of Table 2.

Length deviation: 0.005L

Verticality of pipe cabinet: in accordance with the provisions in Table 3.

Lining: the hardness of the inner surface is not less than 0.5 mm, and the width of the inner surface and secondary inner layer is not less than 1.2 mm. ..

Wall thickness: the minimum length shall not be less than 87.5% of the nominal thickness specified in the drawings approved by the plan application and contract documents, and the absolute value of the difference between the nominal thickness and the average thickness.

3 FRP pipe installation point

1. Before the pipeline is installed and fixed, the equipment nozzle, embedded parts, reserved holes, steel structure and other contents related to pipeline installation shall be rechecked.

2, the slope of the pipeline should be adjusted according to the requirements of the drawings, the adjustment method can be used to meet the slope requirements, and should be set to facilitate maintenance and observation of the weld.

3. Before installation, the pipeline connected with the transmission parts should be leveled and cleaned, and the welding fixed nozzle should generally be far away from the equipment to prevent stress from affecting the welding installation accuracy.

4. Before the pipeline is connected to the system, it is necessary to prevent strong opposition and check the verticality and warping of the flange in a free state.

5, the safety valve should be vertically fixed installation, when put into trial operation, to timely adjust the safety valve. The final adjustment of safety valve is carried out in the system, and the opening and seat pressure meet the requirements of pipeline design documents.

6. Before installing the valve, check its model and material according to the decoration design documents, and confirm its installation direction according to the flow direction of the medium. When the pipeline is connected with the valve by flange or plug-in, the valve switch should be installed in the closed state; If installed by welding, the valve should not be closed.

7. Temporary replacement of instrument components: After all instruments are installed, replace them with temporary components. After pressure testing, flushing and purging, they are formally fixed and installed before feeding.

4 matters needing attention in the use of glass steel pipe

1, due to the small volume density and light material, it is easy to float when installing FRP pipes in high water level areas, so it is necessary to consider setting anti-collision measures such as pier stability or rainwater runoff diversion.

2. In the construction of opening tee and repairing cracks on the installed glass steel pipe, it is required to have completely dry conditions similar to those in the factory building, and the resin and fiber cloth used in the construction need to be cured for 7-8 hours, but it is generally difficult to meet this requirement in on-site construction and repair.

3. The existing underground pipeline detection mainly focuses on detecting metal pipelines, while the nonmetallic pipeline products detection instruments are expensive, and the glass steel pipes cannot be detected after being buried, so other subsequent projects are easy to dig and damage pipelines during construction.

4. The glass steel pipe has poor ultraviolet resistance. The exposed FRP pipe is made of resin-rich layer with a thickness of 0.5 mm, and its surface is coated with ultraviolet absorber to delay the deformation time. With the passage of running time, the resin-rich layer and ultraviolet absorber will not be damaged, thus affecting their service life.

5. The width of covering soil is required to be high. Generally, the shallowest covering soil of SN5000 FRP pipeline under roadway is not less than 0.8m and the deepest covering soil is not more than 3.0mSN2500 FRP pipeline. The shallowest covering soil is not less than 0.8m and the deepest covering soil is not more than1.2m.

6, backfill soil can't contain more than 50mm bricks, stones and other hard objects, in case of damage to the airbag outer wall.

7. At present, there are no reports about large-scale FRP pipes of large water companies in China, and as FRP pipes are emerging high-tech pipes, the water absorption rate is still unknown.

5 price of glass steel pipe