New special mold developed in collaboration with the Belgian manufacturer Ebema

The Belgian concrete construction materials manufacturer Ebema employs a team of around 250 in its three subsidiaries in Zutendaal, Rijkevorsel and Grobbendonk. It generates an annual revenue of nearly 70 million euros. In addition to Ebema_LivingCity, the product line for the public sector, the product line for gardens, patios, driveways and homes is marketed under the name Ebema Stone&Style.

Collaboration based on partnership Ebema is market leader in Belgium for a wide variety of products, both on the residential market as the public market. The name Ebema is a combined short form of “Edel” (precious) “Beton” (concrete) and “materials.”

Ebema was one of Rampf’s first customers in Belgium. This decades-long collaboration based on partnership continues to this day. Together, the two companies have collaborated on many joint developments.

Owning to the decline of space in square metres for conventional paving blocks, Ebema has been looking for possibilities to tap new markets with new products. To this end, Ebema once again sought to Rampf for collaboration.

New product requirements

The objective here was to manufacture façade facing blocks only 2 cm thick. The concrete façade slip can be glued onto various base surfaces and is usually attached to insulation material. Products such as these are frequently used for climate-friendly new buildings and/or renovations. The advantage of these facing blocks of 2-cm thickness is the possibility to use thicker insulation with the same volume, since the outer facing is thinner.

With regard to their manufacture, conventional construction methods for molds do not allow processing of such low product heights for the following reasons:

Almost no standard production machine can use molds with a lower height of 4 cm and cannot manufacture product heights of 20 mm.

A mold of standard design would not be able to resist vibration loads for sufficiently long periods of time, causing the molds to crack and/or break.

Accordingly, it was necessary to develop a new kind of mold to be able to produce this kind of products in a plant that was not originally intended for this purpose.

The mold would therefore have to meet the following requirements:

A stable mold that withstands the vibrations encountered;

Optimal and uniform fill of all mold cells;

Long service life;

Ability to produce different product heights;

Mold usable on various machines;

Exchangeable wear parts;

Large inlet and sliding surface between tamper shoe and mold to reduce wear.

The resulting solution approaches are as follows:

The mold is fitted with a movable slide on its upper side;

The thickness / height of the slide is specified by the height of the concrete product;

The slide, after filling, is hydraulically moved across the mold insert;

The pre-dosed material drops into the mold cell;

The actual mold insert has a height of approx. 100 mm;

The tamper head compresses the quantity in the mold insert pre-dosed by the movable slide.

This now enables Rampf’s customer, Ebema, to use molds of >100 mm height on every machine without difficulty. The mold is, in addition, very stable and wear is minimized by the long guide of the tamper shoe and the mold insert. The tamper head can be equipped with a heater so that the concrete can be processed as wet as possible. This increases the strength of the product. With this mold, strips of 16.5 mm height have already been manufactured. They can bear a weight of 14 kg when placed on two sides.

Vertical stacking the pallet prevents the products from breaking during transport. The strips can be processed very effectively.

Ebema owns the patent for this mold and the process of manufacture of thin products in this way on a standard machine. The Belgian manufacturer collaborates with Rampf to the extent that Rampf manufactures and markets these molds. The customers, however, need a license from Ebema before commencing production.