'Top of Mind' in 3D molds

As one of the world's most renowned manufacturers for concrete molds and formwork systems, Construx Weckenmann has over time developed an extensive portfolio of molds that meet the needs of precast manufacturers. Working closely with the customer, Construx Weckenmann tries to find the most suitable mold that meets all technical specifications, fits within the customer's budget and is suitable for the sizes and numbers of concrete precast elements the customer wants to cast.

For companies supplying precast culverts and cabins such as electrical substations and prison cells, Construx Weckenmann has developed a full range of state-of-the-art molds over the years. Whether fixed geometry, adjustable or fully automated molds, 3D molds are the most complex molds due to the particular design and technical specifications of these elements. As "Top of Mind" in 3D molds, Construx Weckenmann has become the leading supplier for most major European substation prefabricators. Below are some examples from Construx Weckenmann of various molds recently delivered to a number of precast manufacturers around the world. 

Australia: fully automated formwork for divers

The prefabricated concrete culvert elements, manufactured in two hydraulically operated formworks, are cast on their sides and, after demoulding, rotated 90° using a rotary mechanism. Since the elements were to be placed at the base of a bored tunnel, the dimensions of the formworks had to meet very strict technical specifications. The tolerance on joint dimensions (machined sliding joints and upper recess forms with a tongue-and-groove profile) was +/- 0.75 mm. The width, height, diagonal and radius had to be within a tolerance of +/- 1.5 mm.

Geometric requirements of prefabricated culverts:

- Length: 2,380 mm + 170 mm sliding joint.

- Outer width: 4,440 mm.

- Overall external height: 2,995 mm.

- Wall thickness: 300 mm.

- Roof thickness: 300 mm.

- Thickness of the base: 380 mm.

Given the large number of units the customer needed to produce and the high cost of labor in Australia, Construx Weckenmann added a number of features that reduced the unit production cost as much as possible, by making the formwork user-friendly and reducing labor wherever possible. It also installed electronic valves and sensors with PLC controls to ensure proper sequencing and safe operation, according to Australian standards. Special hydraulic and electronic functions of the formworks, to make the formworks user-friendly and reduce labor wherever possible:

- Hydraulic opening and closing of outer panels.

- Hydraulic shrinkage of the inner core.

- Hydraulic fastening of the outer panels to each other.

- Hydraulic fastening of the outer panels to the inner core.

- Hydraulic tightening of the shrinkable inner core.

- Hydraulic unit, including pipes, valves, connections and controls.

- Electronic valves and sensors with PLC controls.

- Remote control for all hydraulic movements.

Northern Ireland: formwork for communication booths

These so-called prefabricated 'Comms Chambers' or communication booths are mainly used in infrastructure works such as airports, railroad projects, roads and housing projects. The formwork is suitable for manufacturing Comms Chambers with inside dimensions ranging from 1,500 mm x 1,500 mm to 3,000 mm x 3,000 mm, with increments of 500 mm in both directions. The inside height can range from 400 mm to 2,400 mm, with increments of 100 mm. The wall and base plate thickness of the elements can be 200 mm, 250 mm or 300 mm. The formwork is suitable for making standard units (with base plate) and attachments (without base plate). The elements are poured upside down and rotated 180° after demoulding using a turning mechanism, also supplied by Construx Weckenmann. Given the large number of units the customer needed to produce and the high cost of labor, Construx Weckenmann's proposal included a number of features to reduce unit production costs as much as possible, by making the formworks user-friendly and reducing labor wherever possible.

Technical specifications of the standard units:

- Inside dimensions of the units, 10 different sizes:

- 1,500 mm x 1,500 mm, 2,000 mm, 2,500 mm and 3,000 mm.

- 2,000 mm x 2,000 mm, 2,500 mm and 3,000 mm.

- 2,500 mm x 2,500 mm and 3,000 mm.

- 3,000 mm x 3,000 mm.

- Units can be molded in any 100 mm increments from 400 mm to a maximum single unit height of 2,400 mm internal height.

- Wall thickness, 3 different options: 200 mm, 250 mm and 300 mm.

- Base plate thickness: 3 different options: 200 mm, 250 mm and 300 mm.

- Tongue and groove connection to add attachments to the base unit/attachment.

- Chamfered joint to add lids to the base unit/attachment.

- Narrowed edges on both short sides, maximum 500 mm x 200 mm.

Technical specifications of attachments (without base plate):

- With similar dimensions and features as the standard units.

- Available in heights of 500 mm, 750 mm and 1,000 mm.

- With wedge connection (tongue and groove connection) at the top and bottom.

The formwork, supplied by Construx Weckenmann, is state-of-the-art, hydraulically operated and equipped with all required safety devices. The formwork is an adjustable and flexible solution for different communication cellars and allows a monolithic casting: walls and base plate at the same time. The hydraulically movable outer panels consist of 4 main parts plus filler panels to meet the different required dimensions. The hydraulically shrinkable inner core consists of 4 shrinkable corner parts plus filler panels. Interchangeable top plates for the 10 different sizes of standard Comms elements are included. These top plates have machine beveled edges and rest on the support structure of the inner core. A height adjustment system allows interior heights from 400 mm to 2,400 mm, with 100 mm increments. Bottom and top cutout shapes create very precise tongue and groove joints.

Poland: fully adjustable substation mold

These substations are cast upside down and rotated 180° after demoulding. This fully hydraulically and electrically operated substation mold is designed to produce 4 different lengths and 2 different widths with the following possible dimensions:

- Inner length adjustable: 3,150 mm, 3,800 mm, 4,200 mm and 4,700 mm.

- Inside width adjustable: 2,600 mm and 3,000 mm.

- Interior height infinitely adjustable from 2,400 mm to 3,000 mm.

- Wall thickness adjustable: 90 mm and 120 mm.

Construx also supplied 2 different upper sections for the inner mold to allow elements to be made with sharp edges between floor and walls or with large chamfers at both ends, a typical feature to accommodate underground pipe connections. The outer mold has hydraulically movable panels. The vibration of the elements is done with high-frequency vibrators. The inner mold has a fixed part and several movable parts, according to the above modularity. The intermediate parts can be placed individually or together. During stripping, first the inner corners are hydraulically pulled down, then the wall panels are pulled down in the same way, creating an 8 mm opening on all sides.

Shaping the Future of Concrete

Construx Weckenmann strives to find the best solution for each customer to produce their precast culverts and pods. This commitment invariably results in satisfied customers. Construx Weckenmann is a technically oriented manufacturing company that builds on the dedication, creativity and experience of its employees. The goal is to establish a partnership with customers and not just act as a supplier, offering complete solutions to precast and formwork issues, both in the factory and on the construction site.