DD294210A5 - PROCESS FOR THE PRODUCTION OF TEETHSTUFFS - Google Patents

Abstract

The invention relates to a method for the production of clay bricks for construction. The solution according to the invention makes it possible to produce immediately, stable, weather-resistant clay bricks from clay with * * clay content and 8-15% water content and addition of * cement after homogenization and shaping with compactnesses of * N / mm2, whose strength corresponds to weak bricks. For non-weathered stones and lower strength of the cement additive can be omitted. {Process; Brick; Clay; adobe; Adobe stone; Erdbaustoff; Normal brick; Cement additive; Preszdruck; Wetterbestaendigkeit}

Description

Field of application of the invention

The invention relates to a method for producing stones from clay for the construction industry. They have a strength comparable to weak bricks and are therefore able to replace them

Characteristic of the known state of the art

In the known, based on long tradition manufacturing process, pit-fresh clay is prepared by adding water, enriched with additives such as straw, animal hair, conifer needles, etc. and formed by hand in boxes.

Immediately thereafter, a demolding of the moist plastic mass with moisture contents of 18 .. .25% and the stone is exposed to a long, mostly natural drying process.

The disadvantages of this production method are low productivity, high manual effort, large space requirement for drying, low quality of the finished clay bricks. Responsible for this are u. a. the high proportion of manual work in the shaping or drying (multiple rearrangement), the long drying time of about 4 weeks under natural conditions (high area requirements), the high drying shrinkage of 5 ... 10%, low strength.

Attempts to mitigate these disadvantages by lime and / or cement additives to wet plastic mass, did not succeed. Due to the high water content of the wet-plastic masses, a high percentage of pores is formed during drying, which largely compensates for the stabilizing effect of the lime / cement additives.

In the dried state, stones produced by these processes have a strength of 2... 3 N / mm ² , ie only low-strength masonry structures can be produced from them. An increase in strength are limited by the high water content limits; Although added to the clay additional water causes the digestion of the clay in a moist plastic mass, but limited on the other hand further compressibility, since the accumulated in the cavities water can not be expelled. Thus, no increase in strength can be achieved by further pressure increase during compression.

Another disadvantage of the stones thus produced is that they are not suitable for masonry exposed to the weather.

Mechanization experiments for the production of clay bricks according to these methods, although improving the labor productivity in the production, but could not reduce the disadvantages of the long drying and cause no quality improvement of the stones.

Object of the invention

The aim of the invention is a method with which it is possible to reduce the manual effort in the production of clay bricks in a simple manner, to increase the labor productivity and to ensure high performance properties of the bricks.

Explanation of the essence of the invention

The invention has as its object to develop a process for the production of clay bricks, which avoids long drying times, allows rapid processability and a clay brick with good dimensional stability, good weather resistance, low shrinkage and a weak fire bricks comparable strength allows.

According to the invention the object is achieved in that

- In a first step, a clay with a clay content of 1O ... 3OMa .-% and a moisture content of 8 ... 15%, which corresponds to dor rule pit-fresh clay, 5 ... 10% cement (based on the mass of clay);

- In a second process step Lehnv / Zementgemlsch is worked through and homogenized;

- In a third step, the homogenized mixture with molding pressures of 5 ... 10N / mm ² formed, for example, pressed to normal stones;

- In a fourth process step the deconsecrated stones are processed immediately.

The clay used with clay content of 10 ... 30Ma .-% and a moisture content of 8 ... 15% corresponds largely to the composition of the pit fresh, natural clay.

If necessary, it can by sand / clay addition and water addition within the first process step au? this required quality will be brought.

The cement additive can be omitted if no weather-resistant clay bricks are needed and a

30% lower dry strength compared to the clay bricks with cement addition is sufficient.

The process is straightforward and can be mechanized by simple, known means.

With the method according to the invention, it is possible in a simple manner to produce immediately processable, stable clay bricks, which are distinguished by dimensional accuracy and low shrinkage. The clay bricks produced in this way are weather-resistant after 7 days and achieve a resistance of weak-fire goat, and can therefore be used at this point.

On long dry periods / large drying surfaces can be omitted. The production is possible with commercial technology and adaptable to different Mecfianisierungsstufen depending on the desired number of stones.

exemplary

The invention will be explained in more detail below using an exemplary embodiment.

For the production of clay bricks, pit-fresh Gothaer clay with clay contents of 20 ± 2Ma .-% was used. The results obtained are summarized in the table below and compared with the production by the known methods.

conventional method according to the invention

Process with cement without cement

additional additive

water content 18 9.5 10.3 (M /%) molding pressure 2.0 7.0 10.0 (N / mm ² ) cement addition - 7.5 - (M /%) dry pressure 3.5 11.5 7.0 strength (N / mm ² ) linear dry 3.25 <0.5 <0.5 shrinkage (%)

Claims (3)

1. A process for the production of clay bricks, characterized in that in a first process step, a clay with 10 to 30% clay content and a moisture content of 8 to 15% 5 to 10% cement (based on the dry clay mass) are added, - in a second process step, the clay-cement mixture is worked through and homogenized, in a third process step, the homogenised mixture is molded with desired pressures of 5... 10N / 'mm ² in the desired size, - In a fourth process step, the stones thus produced are processed immediately. 2. A process for the production of clay bricks according to claim 1, characterized in that achieved by the addition of sand / clay components and possibly water in the first process step, a clay with 10 ... 30Ma .-% clay content and 8 ... 15% water content becomes. 3. A process for the production of clay bricks according to claim 1, characterized in that the cement additive can be omitted if no weather-resistant stones are required and by about 30% lesser dry pressure resistance (compared to stones with cement additive) is sufficient.