In modern brick production, massive investments in infrastructure and machinery dictate the way we make bricks and roof tiles, i.e it will take a lot of effort (not to mention a lot of money) to rearrange a production line or buy new equipment. Still, optimizing production is always a subject of attention. Given a fixed production line, a technical manager soon runs out of options when trying to produce more bricks or tiles. However, leaning on modern chemistry, it is possible to increase the extrusion rate significantly.

 In most production plants I know of, optimizing production is an ever ongoing process. The problem is that unless the board of directors has approved a total refurbish of the production process, most parts are either unchangeable, too difficult or expensive to change.  So, your options moving forward may be one of these listed below.

1. Mechanics of the extruder

This generally sees material and water fed into one end of a pug mill, which uses knives on a rotating shaft to cut through and fold together material in a shallow chamber. The blend is then fed into an extruder at the far end of the mill. The extruder usually consists of two chambers; one to remove air from the ground clay with a vacuum, and the second, a high-pressure chamber, to compact the material so the auger can extrude it through the die. If the knives are worn, or of the wrong shape, the side walls are damaged and the clay throughput may not be fully optimized. The use of inert/non-plastic materials has been seen to be a route cause of this effect. Furthermore, any loss of vacuum or extreme wear on the die can hinder production rates. The cost of continuous replacement of parts, or a total refurb, can affect profitability and make you look for other solutions.

2. More plastic clays

The geopolitical situation has put pressure on clay prices within Mainland Europe. From being an affordable high plastic clay, Ukrainian clay is now five times the price it was before the Russian occupation of Crimea. Not many manufacturers can absorb such an increase in raw material costs and stay competitive, so they have to look further down the list. The use of bentonites have been investigated in detail, but their requirement for extra water can have negative effects further through the process route. 

3. Clay body formulation

Improving and optimizing the body formulation may be a sound opportunity, but it requires extensive research and development.  Only verified, advanced research results may form the basis of such a reform. Companies with this expertise, experience, and capacity in-house, usually conduct such work on a regular basis. All others need to buy this service, which comes at a price, of course. 

4. Use of clay conditioning additives

Different clay conditioners on the market have shown remarkable effects on various stages of the production process. The modern chemical industry has been frontrunners in the development of new and more environmentally friendly additives.

When they are tested and put into production, brick and tile manufacturers experience production efficiency gains in several ways:

  • Increased clay workability and internal body lubrication which gives reduced power requirements and smoother operations
  • Better distribution of the inner particle bonding lead to a higher strength and faster drying times

  • Less use of grog and coarse materials means less wear on extruder blades 

So, unless you have the funds to replace existing machinery and rearrange your line, increasing extrusion rate is about adding something to the clay. The right clay additives will not only increase the extrusion rate but enhance the process both before, during and after the extrusion. At a cost that extensively outperforms the alternative.