Efficiency starts with planning
In order for a deep-freeze warehouse to be economically viable in the long term, it must be geared as far as possible to efficiency – right from the planning phase of construction. This applies both to the structure and the logistical equipment as well as to the racking, the degree of automation and the employees of the warehouse. All the special features that are taken into account in the planning process ensure that there are no unpleasant surprises later on. In general, the prescribed temperature in a deep-freeze warehouse is at least -18° Celsius / – 0.4 Fahrenheit. Therefore, many warehouses maintain a temperature between -30° Celsius / -22 Fahrenheit and -18° Celsius / – 0.4 Fahrenheit – depending on the food they store. Within this temperature range, potential hazards and critical points can be kept to a minimum. In addition, a deep-freeze warehouse complies with the HACCP guidelines, the Hazard Analysis and Critical Control Points. This is a standard that must be adhered to in the food industry.
Dealing correctly with extreme temperature conditions
In particular, the technology used is affected by the low temperatures in a cold storage facility. It must be optimally aligned to the freezing tempratures, otherwise there will be malfunctions and downtimes which can have a negative impact on the profitability of an entire company. The most important prerequisite for any technical equipment used is therefore its resistance to cold. This applies equally to building and insulation materials, screw and plug connections as well as seals, greases and lubricants. The electronics used, such as touch screens in the EDP area or rechargeable batteries, must also be suitable for freezing in any case.
Also not to be underestimated are the special requirements in the area of fire protection, as the automation of the warehouse can be a risk in terms of cable fire or technical defects. Here, too, you should decide during the process planning stage whether you want to use fire fighting with oxygen reduction or sprinklers with an antifreeze system. Pure water is not an alternative in a deep-freeze facility.
Making the best use of cold-resistant materials
The special features of a deep-freeze warehouse in the food industry start with the smallest components. For example, you should use screw or plug connections instead of wiring. These are easier to dissolve at low temperatures and accelerate replacement during maintenance or repairs. This applies above all to the structure of the shelving. It is an absolute must that all materials used for the shelf structure withstand the cold in the long term and are resistant to embrittlement and fractures. This is the only way to prevent security risks, e.g. from falling racks.
In addition, shelving and logistical equipment should be planned in such a way that the cold air can flow unhindered through the warehouse and the stored goods within the deep-freeze warehouse. This is particularly important because of the sensitivity of the food sector: only if the storage strategy is right can the cold reach all products equally – a decisive criterion for adhering to the best-before dates and an uninterrupted cold chain. The latter is one of the most important peculiarities and therefore one of the greatest challenges facing the food industry. From the warehouse to the point of sale, the cold chain must ideally be 100 percent intact at all times. Even a few minutes of interruption can significantly affect the quality of a product. For the planning of a deep-freeze warehouse, this means that there should be as few intermediate logistical stations as possible and as few routes as possible without sufficient cooling.
Consider individual requirements of the products
What a deep-freeze warehouse should do for the storage of food depends above all on its individual requirements. This begins with the ingredients of the product, extends over its best-before date and ends with its packaging. Cardboard, for example, needs a different type of storage than foil. Depending on the type of product, the structure of the facility must also be aligned. Already at the planning stage, you should ensure that the floor has a thicker insulation layer than a ambient temperature warehouse. This must be highly loadable and, in the best case, have an anti-freeze heating system that prevents the water in the floor below the racking from freezing and lifting or deforming the floor. The anchoring of the planned shelves is also closely related to the condition of the floor. It is advisable to involve an expert warehouse technology consultant at an early stage who knows exactly which anchorage is suitable for which floor. Especially in deep-freeze warehouses, it makes sense in most cases to use mobile racking systems. These are particularly efficient for deep-freeze warehouses due to the saving of expensive hall space. Each shelf is mounted on a base which is electrically movable. The bases run on rails embedded in the floor. In the case of static pallet racks, these have to be anchored deep and ensure particularly safe storage of the goods.
For the façade of a deep-freeze warehouse, the use of so-called PUR panels is ideal. These are made of polyurethane and are very cold-resistant. The same applies to the roof of a deep-freeze warehouse – This should also be rainproof. In addition, pay close attention to your door and gate systems. Thermal bridges in those areas can have serious effects on the entire deep-freeze warehouse. As the air inside the warehouse is much drier than outside, humidity from outside can lead to ice formation and cause doors or gates to freeze. This in turn leads to malfunctions of the entire operating procedure. The same applies to the formation of draughts, which you should also avoid by means of appropriate seals. Floor and wall heating systems can also help in this context.
Risk factor standstill
If a malfunction or even a standstill occurs within a deep-freeze warehouse, this inevitably means rising costs. If work in the warehouse does not continue, all subsequent items in the supply chain will be delayed and will affect the profitability and efficiency of the whole operation. The main source of error lies in the human factor. The extreme temperatures are not harmful per se, but they expose the body to corresponding stresses – which rise with decreasing temperature. Suitable work clothing and regular health checks are therefore a must. Human error can only be limited if the working conditions are optimal despite the cold temperatures.
Mainly in the area of deep-freeze warehouses, it is advisable to rely on a high degree of automation. Modern automation technology can significantly increase the performance of a warehouse, improve delivery capability and control operating costs. At this point, it is important to use a heated system control and heated switch cabinets. Even when the facility is at a standstill, the heating must continue to run in order to prevent frost damage to the conveyor system and maintain its operational capability. This is the only way to ensure that the issue of energy demand does not become a cost-intensive burden on operations. The general rule is: the more automatic, the more effective.
It is also advisable in any case to seek advice from a competent partner right from the start, who will support the planning and execution of the construction of a deep-freeze warehouse on site. As an expert, he/she knows the peculiarities and challenges of the sensitive food sector and can evaluate them accordingly. So anyone who pays attention from the outset to incorporating the strict labour and food regulations into the planning of a storage facility has taken the first step towards a safe, efficient and cost-saving deep-freeze warehouse.