SU923845A1 - Pressure pipe production method - Google Patents

Description

The invention relates to the arbitrariness of precast concrete and reinforced concrete.

The closest to that proposed by the technical entity is a method of manufacturing pressure pipes, including the installation of strained longitudinal and spiral reinforcement, laying the concrete mix into a form with simultaneous vibration compaction, hydraulic pressing and heat treatment ΓΙ '].

The disadvantages of this method are significant energy consumption and not a high quality of products.

The purpose of the invention is to increase quality and reduce energy intensity.

This goal is achieved by the fact that in the method of manufacturing pressure vessels (a cut, including the installation of tensioned longitudinal and spiral reinforcement, 20 laying the concrete mixture into a form with its simultaneous vibroplate, hydraulic pressing and heat treatment, hydraulic pressing is carried out at a pressure of 0.7-1, 5 MPa, and the installation of 25 spiral reinforcement is carried out after heat treatment on the surface of the molded product winding with tension, followed by the application of a protective coating.

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The proposed method for the manufacture of pressure pipes as follows.

After assembly, the outer shape, equipping the longitudinal rod and armature .predvaritelnogo, tension rods outer shape mans core and transported to the post concreting where osuschest ⁴ vlyayut vibromolding pipe. Next, the form set on the post of hydraulic pressing and heat treatment. Forcing water into the space between the base of the core and the rubber boot, pressurize the fresh concrete. With a constant pressing pressure of 0.7-1.5 MPa for all pipe diameters, the concrete is heat treated before it acquires a stripping strength of 30-45 MPa. At the end of the heat treatment, the steam is turned off and the pressure is lowered. Then, the core hose is disconnected from the high pressure line and the core is transported to the dismantling post. After stripping the core is installed on the post winding ki spiral fittings. To do this, using a tensioned device with

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the control device produces the stress of the reinforcement and the laying _e of the grooves on the surface of the core, formed by vibrating the concrete mix with a profile located in a spiral on the inner surface of the outer form. Then, grooving the grooves with reinforcement with an anticorrosive composition, which is used, for example, polymer cement 10 concrete, which has a high adhesion ability to the concrete of the pipe core, is carried out. Fixing the ends of the spiral reinforcement is done by welding them with core plates that are 15 in the core. . After striking the grooves with an anticorrosive composition, forming a protective outer layer, the inner diameter of the socket of the pipe is normalized, and after three ~ ₂ days daily exposure, hydraulic tests of the pipe are performed, then the pipe is marked and sent to the finished product warehouse.

According to СН 324-72, reinforced concrete pressure vibro-pressed pipes produce three strength classes, pressure testing pipes for each strength class are installed depending on the diameter ..

Pressure (3.0-3-5 MPa). The proposed manufacturing technology due to the absence of a spiral frame allows to reduce the magnitude of the pressing pressure to 0.7-1.5 MPa for All pipe diameters. This value is established experimentally and is optimal for obtaining high physicomechanical properties of concrete in the pipe walls. At the same time, the reduction in pressure to a value of less than 0.7 MPa leads to a decrease in the quality of the pipe due to an increase in the water absorption of concrete, and an increase in the pressing pressure above 1.5 MPa does not improve the strength characteristics of the pipe, but leads to a significant increase in energy consumption (tab. one).

Table 1

The magnitude of the pressing pressure, MPa Diameter. pipes, mm ----------- Water absorption, % Crack resistance, to GS / cm ¹ } - Compressive strength of layers, kgf / cm ¹ } Electricity consumption ' kw protective main 0.3-0.65 800 7-6 18 300 300 22-30 0.3-0.65 1000 7-6 18 300 300 22-30 1200 also also also also also 0.7 ^ 1.5 800 4-3 thirty 500-550 500-550 . 31-38 1000 also also also' also also 1200 also also also also also 1.6-3.3 800 4-3 thirty 550 550 40-68 1000 . also also, also also also 1200 " one -. ' ¹ - _ 1 1 ~ - one ' -

PRI me R 1. For the manufacture of pipe 1 strength class diameter. 500 mm after vibroforming, hydraulic pressing is carried out at (pressing pressure of 0.7 MPa. Heat treatment of the concrete core until it reaches a strength of 45 MPa is carried out for 12 hours at a constant pressing pressure of 0.7 MPa. At the end of the heat treatment, descent of the pressing pressure and dismantling, the core is transported to post winding spiral reinforcement, which is used as the wire B-P with a diameter of 3 mm With the help of a tension device, the reinforcement is produced to a value of 1400 kgf / cm. The reinforcement is laid urs in kanav- ki on the molded surface of the core followed by applying to it a protective layer ^60, as koto- _(cerned, polymer concrete is used. Then normalize the inner diameter of the socket, and after three-day exposure produce gidravliches65, Kie test tubes. Physicochemical mehani5

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The concrete concrete properties of the walls of a 500 mm diameter pipe are as follows:

Compressive strength, kgf / cm% protective outer layer - 460-500

base layer - 480-510 5

Water absorption,%: base layer - 3

protective layer - 3

Water resistance of concrete walls, kgf / cm ¹ ) - - 18 U

Crack resistance

kgf / cm - 2.2.5

Pr em e 2. For the manufacture of pipes of the first strength class, 5 with a diameter of 1600 mm after vibroforming. Hydraulic pressing of the form with a ferro-concrete core is carried out at a pressing pressure of 1.5 MPa.

Heat treatment of concrete core is carried out for 12 hours at a constant pressing pressure of 1.5 MPa. At the end of the heat treatment, the descent of the pressurized pressure and the stripping, the spiral reinforcement is wound, which is used as the wire B-P with a diameter

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8 mm. With the help of a tensioning device, the reinforcement is produced to a value of 14,000 kgf / cm ^. Carry out the installation of reinforcement in the grooves on the molded surface of the core with the subsequent application to the reinforcement of the protective layer, which is used polymer cement. After normalization of the inner diameter of the socket and a three-day exposure produce hydraulic tests of the pipe. The manufactured tube has the following physical and mechanical properties:

Compressive strength, kgf / cm: protective outer layer -520-550 main layer _ 520-550

Water absorption,%: base layer - 3

protective layer · - 3

Water resistance of concrete walls, kgf / cm ^ - 22 Crack resistance,

kgf / cm ^ - 26-30

The results of comparative tests of pipes with a diameter of 1600 mm, manufactured according to the known and proposed methods are summarized in table 2.

table 2

Indicators Way Famous Proposed (CH-324-72) ° Opressovoe pressure MPa 1.5 3.3 Compressive strength, kgf / cm ^: base layer of concrete 500 550 protective layer 300 550 Water absorption,%: base layer five 3 protective layer ten 3 Water resistance of pipe walls, kgf / cm ¹ } - 0.5-8 22 / <1 Crack resistance, kgf / cm ⁴ 20-22 26-39 Electricity consumption, kW 54-55 31-38

The use of the proposed method in the building materials industry can improve the quality of 60 and reduce the energy intensity of manufactured products from concrete mixtures.

Claims (1)

Claim . A method of manufacturing pressure pipes, including the installation of voltages pro- 65 Floor and spiral reinforcement, laying of the concrete mixture with its simultaneous vibrocompaction, hydraulic pressing and heat treatment, characterized in that, in order to improve quality and reduce energy consumption, hydraulic casting is carried out at a pressure of 0.7-1.5 MPa, and installed 7 923845 8 ! V KU spiral fittings carried out after heat treatment on the surface of the molded product winding with tension, followed by the application of a protective coating. .