Method for evaluating point load performance of plastic tube

Abstract

The invention relates to a method for evaluating the point load performance of a plastic tube. The method comprises the following steps: 1, forming a notch on the outer wall of the plastic tube, wherein the depth of the notch is lower than the wall thickness of the plastic tube; 2, allowing the formed notched plastic tube to be full of a first liquid, and sealing two ends of the plastic tube to obtain a plastic tube sample for detection; and 3, putting the plastic tube sample for detection in a sealable container, allowing the sealable container to be full of a second liquid, sealing the sealable container, and carrying out hydrostatic test. The method for evaluating the point load performance of the plastic tube substantially shortens the evaluation time, and the dispersivity of evaluation results is small.

Description

technical field

[0001] The invention relates to a method for evaluating the point load performance of plastic pipes. Background technique

[0002] With the application and development of high-efficiency, low-cost, environmentally friendly non-excavation and other non-traditional installation technologies (such as pipe bursting method, plowing method, directional drilling method, sand-free landfill, etc.), the point load resistance of plastic pipes Performance requirements are getting higher and higher. When non-traditional techniques such as non-excavation are used to install plastic pipes, the outer surface of plastic pipes is easily scratched by rocks, causing scratches to form micro-cracks; even the edges and corners of stones are pressed into the outer wall of the pipe to a certain depth. The above installation reality causes plastic pipes to bear additional local point loads during pressure-bearing operation, and such point loads have an important impact on the service...

Examples

Embodiment 1

[0037] This example is used to illustrate the method for evaluating the point load performance of plastic pipes provided by the present invention.

[0038] Sample: PE100 pipe, outer diameter 110mm, minimum wall thickness 10.48mm, SDR 11, length 700mm;

[0039] Reagent: 2% by weight Arkopal N100 surfactant solution, purchased from Sigma-Aldrich Company.

[0040] Evaluation process:

[0041] (1) Place the PE100 pipe at ambient temperature for 24 hours, then use a twist drill with a 90° cone angle and an outer diameter of 12mm to drill holes at the minimum wall thickness to form a conical shape with a depth of 5.24mm and a cone angle of 90° Notch, then leave for 24 hours.

[0042] (2) Install a head on one end of the pipe formed with a gap, inject 2% by weight of Arkopal N 100 surfactant solution, and then install a head on the other end of the pipe (the head has a hydraulic interface and an exhaust port). Then continue to add the surfactant solution through the vent until th...

Embodiment 2

[0047] This example is used to illustrate the method for evaluating the point load performance of plastic pipes provided by the present invention.

[0048] The point load performance of the PE100 pipe was evaluated according to the method of Example 1, except that in step (3), the container was also filled with 2% by weight of Arkopal N100 surfactant solution.

[0049] As a result, the tubing samples failed after 206 hours.

Embodiment 3

[0051] This example is used to illustrate the method for evaluating the point load performance of plastic pipes provided by the present invention.

[0052] Evaluate the point load performance of PE100 pipe according to the method of Example 1, the difference is that in step (4), the pressure inside the pipe sample is adjusted to 17.8bar, and the pressure outside the pipe sample is adjusted to 6.0bar .

[0053] As a result, the tubing samples failed after 217 hours.

technical field

[0001] The invention relates to a method for evaluating the point load performance of plastic pipes. Background technique

[0002] With the application and development of high-efficiency, low-cost, environmentally friendly non-excavation and other non-traditional installation technologies (such as pipe bursting method, plowing method, directional drilling method, sand-free landfill, etc.), the point load resistance of plastic pipes Performance requirements are getting higher and higher. When non-traditional techniques such as non-excavation are used to install plastic pipes, the outer surface of plastic pipes is easily scratched by rocks, causing scratches to form micro-cracks; even the edges and corners of stones are pressed into the outer wall of the pipe to a certain depth. The above installation reality causes plastic pipes to bear additional local point loads during pressure-bearing operation, and such point loads have an important impact on the service...

Examples

Embodiment 1

[0037] This example is used to illustrate the method for evaluating the point load performance of plastic pipes provided by the present invention.

[0038] Sample: PE100 pipe, outer diameter 110mm, minimum wall thickness 10.48mm, SDR 11, length 700mm;

[0039] Reagent: 2% by weight Arkopal N100 surfactant solution, purchased from Sigma-Aldrich Company.

[0040] Evaluation process:

[0041] (1) Place the PE100 pipe at ambient temperature for 24 hours, then use a twist drill with a 90° cone angle and an outer diameter of 12mm to drill holes at the minimum wall thickness to form a conical shape with a depth of 5.24mm and a cone angle of 90° Notch, then leave for 24 hours.

[0042] (2) Install a head on one end of the pipe formed with a gap, inject 2% by weight of Arkopal N 100 surfactant solution, and then install a head on the other end of the pipe (the head has a hydraulic interface and an exhaust port). Then continue to add the surfactant solution through the vent until th...

Embodiment 2

[0047] This example is used to illustrate the method for evaluating the point load performance of plastic pipes provided by the present invention.

[0048] The point load performance of the PE100 pipe was evaluated according to the method of Example 1, except that in step (3), the container was also filled with 2% by weight of Arkopal N100 surfactant solution.

[0049] As a result, the tubing samples failed after 206 hours.

Embodiment 3

[0051] This example is used to illustrate the method for evaluating the point load performance of plastic pipes provided by the present invention.

[0052] Evaluate the point load performance of PE100 pipe according to the method of Example 1, the difference is that in step (4), the pressure inside the pipe sample is adjusted to 17.8bar, and the pressure outside the pipe sample is adjusted to 6.0bar .

[0053] As a result, the tubing samples failed after 217 hours.

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