DE558216C - Process for the production of hollow bodies of all kinds from concrete, reinforced concrete, asbestos cement o. - Google Patents

Description

Process for the production of hollow bodies of all kinds from concrete, reinforced concrete, Asbestos cement or the like. The subject matter of the invention is a method of manufacture of all types of hollow bodies made of concrete, reinforced concrete, asbestos cement or the like, in particular of pipes, accelerating the setting of the mass by heating. According to the invention the mold jacket z. B. heated by a heating medium flowing through its channels, so that the setting process from the outer surface of the hollow body to the inner Boundary surface to progresses. This way the setting will be the outer Concrete layer accelerates and that of the inner concrete layer slows down, whereby only a small amount of force is required to pull out the core and is therefore quick and cheap production of pipes or the like. Hollow objects of any length and diameter is made possible.

In order to facilitate the extraction of the core, according to the invention the core kept circulating during the hardening of the mass and to a suitable one To be able to choose the point in time at which the outer concrete layer is already sufficiently hardened serves as a solid base for the still plastic inner concrete layer and consequently no excessive force is required to pull it out; is a measuring device provided at which the increase in the force required with the solidification can be read for the circulation. The method according to the present invention is illustrated in the drawing. It shows Fig.i the shape in cross section, Fig. 2 the shape in longitudinal section.

The form consists of a multi-part, e.g. B: three-piece coat i, a, 3 with removable end walls 4 and 5 and from a hollow core 6, z. B. a iron drill. In the mold jacket there is a series of outwardly tapering openings 7, furthermore an opening 8 for inserting the concrete pipe 9 and finally a row provided by longitudinal channels io.

The device also contains a concrete container, not shown, from which the liquid concrete z. B. by means of compressed air through line 9 in the Form is promoted. To clean the opening 7 a comb i i to 1a is provided, the pitch of the pins i i corresponds to that of the opening 7. This comb can be operated manually or mechanically.

When the mold is filled, the superfluous escapes through the openings 7 Water, which sometimes also carries away concrete. The concrete should be carried away the outwardly tapering shape of the openings 7 are prevented as much as possible. However, in order to reliably prevent the openings 7 from being clogged, during this work stage the openings 7 cleaned by the comb i i to 12 as required. After this the filling of the form with concrete or the like. Performed and the excess water squeezed out of the concrete becomes the outer concrete layer of the body produced warmed up. For this purpose, the mold jacket is heated to an appropriate temperature, e.g. B. by the supply of hot steam, hot air or the like. In the channels io, brought about the setting of the outer concrete layer accelerates and the setting of the inner one Concrete layer is delayed.

At a time when the inner concrete layer is still soft the core 6 is pulled out. This point must be careful be determined. Failure to do so would result in complete setting of the inner Concrete layer and lead to such a solid enclosure of the core 6 that its Pulling out would be impossible.

To determine when to pull out the core, the core in the heated concrete is temporarily or continuously put into circulation. As a result the progressive setting of the concrete decreases the friction of the core in the concrete to, and accordingly the effort required to rotate the core 6 also increases. This growing effort is measured, z. B. with the help of an ammeter. As soon as this effort has reached an empirically predetermined level, the core pulled out of the concrete.

Claims (2)

PATENT CLAIMS: i. A method for producing hollow bodies of all kinds from concrete, reinforced concrete, asbestos cement or the like, in particular pipes, wherein the setting of the mass is accelerated by heating, characterized in that by heating the mold shell, e.g. B. by a heating means flowing through its channels, the setting process proceeds from the outer surface of the hollow body to the inner boundary surface. 2. The method according to claim i with a during the molding process revolving core, characterized in that the core during the hardening of the mass obtained in rotation and according to the requirements required for this, Pulled out the force exerted on a measuring device from the hollow body will.