SU1576343A1 - Method of producing tubular articles from concrete mixes - Google Patents

Abstract

The invention relates to the production of tubular products from concrete mixtures and allows for an improvement in the quality of molded products. This is achieved in that the compaction is carried out in two stages. Moreover, the direction of circular vibration in the second stage back to the direction of circular vibration than in the first, the amplitudes of oscillations applied to the upper end of the form are equal in both stages, and to the lower end in the second stage are 0.3 amplitudes of oscillations of the first stage.

Description

This invention relates to the manufacture of tubular products.

The purpose of the invention is to improve the quality of molded products.

The method is carried out as follows.

The column with the exciters of circular oscillations, which is permanently installed at the forming station, is hung with the inner form assembled with the outer one. Then, a concrete mix is fed into the cavity between the inner and outer molds and at the same time it is vibrated. The product is molded and compacted in two steps. At the first stage, the molding and compaction of the lower, middle and upper parts of the product are carried out under the vibration of circular oscillations with a calculated amplitude. At the second stage, the compaction is carried out by vibration action with circular oscillations, the direction of movement of which is opposite to the direction of oscillations at the first stage. The upper part of the product is sealed with circular oscillations with a calculated amplitude. Bottom

the part vibrates with an amplitude of no more than 0.3 calculated, and the middle one with a total amplitude is proportional to the distance to the vibrators.

After that, the molded product is fed to the post of hydraulic pressing and heat treatment.

Example 1 In the process of filling a mold with a concrete mixture, the lower and upper parts of the product vibrate in circular directions in the same direction with the calculated amplitude: the lower part is 0.3 mm, the upper one is 0.7 mm, and the middle one is the total amplitude proportional to the distance from the m to the upper and lower vibrators.

After filling the mold with a concrete mixture, the circular oscillations are reversed and the vibration effect on the upper part of the product is carried out with an amplitude of 0.7 mm, and the lower one is vibrated with an amplitude of 0.09 mm. With such a change in the characteristics of circular oscillations, the concrete mix is uniformly compacted in the lower, middle and upper parts of the product.

SP

J

about

00

From

Example 2. In the process of filling a mold, the concrete mix is vibrated in circular oscillations in one direction. The lower part vibrates with an amplitude of 0.3 mm, and the upper part with an amplitude of 0.7 mm. When the concrete mix fills 2/3 of the mold height, the circular vibrations are reversed. The upper part of the product is vibrated with a calculated amplitude (for example, 0.7 mm for a pipe of 1200 mm), and the lower one is reinforced by vibration with an amplitude of no more than 0.09 mm. When the direction of circular oscillations is reversed and the amplitude of oscillations in the lower part of the product decreases, the concrete mix is uniformly compacted along the length of the product.

Example 3. At the first stage, simultaneously with the start of the concrete mix in the form, include the upper and lower vibration exciters of circular oscillations. The process of molding and compacting the concrete mixture is carried out by rotating the upper and lower exciters in the same direction with the calculated amplitude. Then, when the lower part of the product is formed, without interrupting the flow of the concrete mixture into the mold, the rotation of the upper and lower exciters is changed.

reversed. Simultaneously with the change of rotation, the magnitude of the driving force is also changed: the upper exciter generates oscillations with the calculated amplitude for this product, for example, 0.7 mm for a pipe with a diameter of 1200 mm, and the lower exciter generates oscillations with an amplitude of not more than 0.3 calculated, i.e. . 0.3-0,, 09 mm for the bottom of the product.

Claims (1)

Invention Formula A method of manufacturing tubular products from concrete mixtures, including assembling a form, feeding and compacting a concrete mix under vibration of circular oscillations applied to the upper and lower ends of the mold, characterized in that, in order to improve the quality of the molded products, the compaction is carried out in two stages, with the direction of movement of circular vibrational effects in the second stage back to the direction of circular vibration effects on the first, the amplitude of oscillations applied to the upper end of the form at both stages are equal, and to the lower at the second stage, it equals 0.3 amplitudes of oscillations of the first stage.