Application of a thermostatic chamber in curing precast concrete elements

Controlled curing for a faster and more predictable process

As the scale of construction projects continues to grow, precast concrete manufacturers must combine high product quality with increasingly short order lead times. One of the main stages limiting production speed is concrete curing - a process essential for achieving the required strength, but difficult to accelerate under natural conditions and strongly dependent on ambient temperature.

At the precast plant described in this case study, the problem was addressed by implementing a custom POL-EKO thermostatic chamber. The chamber made it possible to cure concrete under controlled conditions, improving process repeatability and enabling more efficient use of moulds, production space and operator time.

Natural curing limited plant output

In a conventional process, precast elements remain in their moulds until they have developed sufficient strength for safe demoulding, handling and further processing. This time depends not only on the concrete mix design, but also on ambient temperature and humidity.

For the plant, this created several significant limitations:

• long and variable waiting times before demoulding,
• limited mould availability for subsequent production cycles,
• substantial floor-space requirements for curing products,
• different curing rates in summer and winter,
• difficulty planning subsequent production batches precisely,
• the risk of defects caused by uneven thermal conditions,
• the need to handle heavy racks and moulds safely.

The objective was therefore not simply to raise the temperature around the precast elements. The key requirement was to create a controlled process that would heat the entire load evenly, protect the moulds from overheating and allow a repeatable curing cycle to be programmed.

Custom POL-EKO thermostatic chamber

To meet the plant requirements, a thermostatic chamber was designed around the dimensions of the precast elements, their handling method and the organisation of the production line.

POL-EKO designs custom thermostatic chambers for industrial applications. Depending on the process, the equipment can include programmable control systems, parameter recording, pass-through doors, panic-release handles, signal towers, loading platforms and trolleys. The construction, temperature range, air circulation system and accessories are selected for the specific technological process.

In this project, particular attention was paid to:

• loading complete racks containing moulds,
• adapting the workspace for forklift handling,
• uniform distribution of heated air,
• temperature control in different areas of the chamber,
• protecting moulds against local overheating,
• recording the process cycle,
• safe operation of the equipment,
• efficient material flow through the production line.

A pass-through design was used. Racks containing the precast elements enter the chamber from the loading side and are removed from the opposite side after curing. This arrangement improves logistics, reduces crossing transport routes and creates an orderly production flow.

Operator safety and process protection

In industrial equipment, safety must cover both the operator and the load inside the chamber. The chamber was therefore equipped with protective solutions matched to the way it is used.

The principal safety features include:

• a signal tower indicating the operating status,
• easily accessible mushroom-type emergency stop switches,
• an internal panic-release handle for opening the door,
• protection against critical parameter limits being exceeded,
• ventilation and controlled air circulation,
• alarm status indication,
• design features supporting safe loading and unloading.

Custom POL-EKO chambers can be equipped with panic-release handles, emergency lighting, parameter-limit alarms and electrical and thermal protection systems. Precise temperature control also protects the moulds, especially materials susceptible to deformation or accelerated ageing during prolonged exposure to high temperatures.

A chamber designed around the customer's process

Effective curing of precast elements requires a solution matched to actual production conditions. The temperature range and heating capacity are important, but so are the dimensions and mass of the load, the type of moulds, the loading method, permissible material temperatures, heating and cooling rates, sensor arrangement, internal transport and data-recording requirements.

As with other POL-EKO custom equipment projects, the work includes analysing user needs, preparing a concept, selecting equipment and implementing a complete solution. This approach treats the chamber not as a stand-alone heating device, but as an integral part of the entire technological process.