Kefengyuan Home > News > Common problem >

Products

Common problem

The difference between the krah pipe and other pipes.

Release time:2018-12-18 09:47

What is the difference between several kinds of drainage pipes, such as corrugated tubes, hollow pipes and fiberglass pipes? Today, we have to talk about the advantages and disadvantages of carat tube and other kinds of drainage pipes.

1. Comparison of national standard numbers
1, the national standard number of Crabbe: GB/T19472.2-2004.
2, HDPE double wall bellows national standard number: GB/T19472.1-2004.
3, HDPE hollow wall tube national standard number: GB/T19472.2-2004.
4, UPVC double wall bellows national standard number: GB/T18477-2001.
5, glass steel tube: HGJ 534-1991 HG/T 21633-1991.

Two. Contrast of molding process
1, carat tube forming process:
Clark tube is extruded by the main extruder, U-shaped belt extruded by the sub-extruder and wrapped with PP skeleton tube winding on the mold. It is continuously monitored and controlled by computer during the whole production process, and cooled by rolling natural wind. The carat tube is a hot melt winding process.
2, HDPE double wall bellows molding process:
HDPE double wall bellows are pipes that are directly extruded through two concentric tube embryos and are molded by suction. It is an extrusion process.
3. HDPE hollow wall tube forming process:
HDPE hollow wall tube is completed by two extruders. The main extruder extrudes the tube into a square tube after vacuum setting and water cooling. Then the square tube is wound to the molding machine. At the same time, the auxiliary extruder extrudes the auxiliary material and fills the gap. During the welding process, water cooling must be used continuously to keep the tube embryo from happening. Heated deformation.
4. UPVC double-wall corrugated pipe forming process: UPVC double-wall corrugated pipe is extruded by direct extrusion of two concentric tube embryos, and by suction molding of the tube, using extrusion molding.
5. Forming technology of FRP pipe: FRP pipe for sewage discharge is mainly made of powder admixture, using short glass fiber centrifugal or long fiber winding technology.
6. Forming technology of PE spiral bellows with metal inner reinforcement: the middle layer of the product is strengthened by steel strip, and the inner and outer layers are polyethylene. Adopt water cooling method.
Three. Comparison of process and structure characteristics

1. Technology and structure characteristics of carat tube

1) adopt hot winding and natural wind rolling cooling, the structure wall has no internal stress and no weld. The wall thickness of the pipe is uniform.
2) The expansion coefficient of polyethylene material is large. When the expansion and cold shrinkage occur, the outer ribbed pipe and backfill soil act together, which will effectively restrain the longitudinal displacement of the pipeline system, prevent the stress concentration at both ends of the pipeline, and destroy the connection with the inspection well.
3) Large diameter pipes can be produced by winding. Ring stiffness of pipes can be increased by using spiral ribbed pipes. The ring stiffness is more than 20 KN/m2, and it can be adjusted continuously, and the maximum burial depth can reach 20m.
2, HDPE double wall bellows technology and structural characteristics:

1) extrusion is adopted, and the appearance of pipes is better.

2) the length of 12m pipe can be produced.

3) By the process equipment and extrusion die, the pipe produced by the smaller diameter, mainly to produce DN 1200mm below the pipe.

4) The ring stiffness of HDPE double-walled bellows is much lower than that of wound B-type bellows, mainly at the top of S1 and S2. When the diameter is greater than or equal to DN800, the ring stiffness is difficult to reach 8KN/m2.

3, HDPE hollow wall tube technology and structural characteristics:

1) There are stresses in the wall of the structure by winding and water cooling, and there are hidden dangers in actual use.

2) in cold welding, the weld length is long and the weld quality is difficult to guarantee.

3) The outer wall is smooth, which can not effectively restrain the longitudinal displacement caused by the thermal expansion and cold contraction of PE material. It often causes stress concentration at both ends of the pipeline, and destroys the connection between the joint or the pipeline and the inspection well, resulting in water leakage.

4) the maximum ring stiffness is 8 KN/m2.

5) the port of the pipeline is flat port, and the port shrinks after water cooling.

4, UPVC double wall bellows technology and structural characteristics:

1) extrusion is adopted, and the appearance of pipes is better.

2) the length of 12m pipe can be produced.

3) Influenced by the process equipment and the melt flow rate of UPVC material, the diameter of the pipe produced is small, mainly producing DN500mm pipes.

4) The ring stiffness of UPVC double-walled bellows is much lower than that of the wall tubes of the winding B-type structure, which mainly consists of S1 and S2.

5. Technology and structural features of FRP pipes:

1) powder mixing, short fiber centrifugation or filament winding. The pipe wall is a composite material wall, which is composed of an outer wall (resin, sand, fiber), a reinforcing layer (resin, fiber), a structural layer (resin, sand, fiber), and a liner (resin) composite material.

2) The pipe wall is made up of composite materials, and the inner and outer walls of the pipe are made of unsaturated polyester resin, which is easy to be destroyed. Glass fiber is mixed with water and pollutes the water source. Short fiber centrifugal tube has high brittleness and stiffness. It can not be repaired when it is damaged by collision and scraping during transportation and construction, and the wound is easy to tear and extend.

6, metal reinforced PE spiral bellows technology and structural characteristics:

The winding process is used to form the pipes and the pipes are water-cooled. The pipe structure wall is composed of polyethylene and metal materials. Because of the big difference between the indexes of polyethylene and metal materials, there are stresses between the structure walls, and there are hidden dangers in practical use.

Four, pipe diameter contrast:
1, the caliber of the carat tube is DN300mm-DN4000mm
2. HDPE double-wall corrugated pipe caliber: mainly produces DN 600 mm below the pipe, a small number of domestic manufacturers can produce DN 1200 mm below the pipe, but the actual application is not many.
3. The diameter of HDPE hollow wall tube is below DN3000mm.
4, UPVC double wall bellows tube diameter: DN500 below.
5. Diameter of glass fibre reinforced plastic pipe material:


  Next:no   Prev:no

Tel

Top