White paper: carousel dishwashers

White paper: carousel dishwashers

Carousel dishwashers are a special variant of normal rack-type dishwashing machines and therefore are included in the family of automatic dishwashers, also known as “tunnel” dishwashers. This type of dishwasher is designed for baskets that continue to enter and exit the machine, guaranteeing the washing of a large number of dishes.

How do carousel dishwashers work and how are they made? In this white paper, we go through the features and main components of this particular kind of dishwasher.

Main features of Carousel dishwashers

Carousel dishwashers (occasionally also called circular dishwashers), are a mix between a rack-type dishwasher and a flight-type dishwashing machine. The main feature of carousel plant is that the baskets are conveyed in a closed path composed of two straight sections interspersed with two semi-circular curves. The dishwasher zone is placed in one of the two straight sections, while the other section is designed to act as a loading/unloading area. It means that these washing solutions are bulkier than a rack conveyor dishwasher, in fact the size in length and width can even reach 8.5 x 2 m.

Below some advantages related to the carousel systems:

  • Ease of use – They are convenient because the dishes are loaded directly into the baskets without first being stacked or accumulated; moreover, the racks themselves have not to be managed by the operators as they continue to circulate along the path of the dishwasher. For this reason, the actual productivity is higher than the one of a rack-type dishwasher of the same size.
  • They can be left unattended for a few moments as they will continue to work even if the operator is not there; on the other hand, a flight dishwashing machine will stop if a dish hits the end of the conveyor without being removed.
  • They require fewer personnel: the loading and unloading areas are placed in the same point and the same operator can therefore perform both functions.
  • In canteens, a portion of the straight section can be left exposed, so that users at the end of the meal place the dirty dishes directly on the baskets. The kitchen staff will only have to take care of collecting the clean dishes coming out of the dishwasher.

The carousel dishwashers have a structure in AISI 304 steel (i.e. 18/10 steel) and AISI 316 with a modular construction and, depending on the size and complexity, they can be composed of:

  1. loading area (dirty dishes);
  2. straight section;
  3. pre-washing module;
  4. one or more washing modules;
  5. rinsing;
  6. (if present) drying system;
  7. curves;
  8. unloading area (clean dishes).

Fig.1: Example of carousel dishwashing machine (Elframo branded)

The productivity of these systems is similar to that of traditional rack conveyor dishwashers (approximately between 50 and 300 baskets/hour depending on the size of the system). However, there is a relevant improvement in the working conditions for operators, as they are not the ones who have to handle the inlet and outlet baskets. The power absorbed by the machine depends on its size. In general, however, it is higher than the power absorbed by a rack-type dishwasher of the same size, because it cannot be equipped with an economizer (therefore, the individual modules cannot be put on stand-by due to the continuous transit of the racks). In the case of faster machines, it is necessary to adopt enhanced the washing modules. The transport system can move clockwise or counterclockwise based on the customer’s need. The carousel machines are intended for large canteens of companies, schools, hospitals, hotels or ships, where there is a constant and continuous need to wash a high volume of dishes.

Carousel dishwashers allow you to wash glasses, cutlery, flat or deep plates, trays or small pots, using only a different type of basket (specific for each object to be washed). So, at the same time, on the carousel you will find different types of baskets.

Although there are clear savings in terms of personnel in the adoption of carousel machines, in Italy and Europe the demand for this type of solution is not high. On the other hand, the demand is much higher in extra-European countries.

How a carousel dishwasher is made

The carousel dishwasher has many points in common with the rack conveyor dishwasher, which we have already dealt with in detail in the previous white paper. The main distinguishing features are listed below.

Transport system – These solutions are also equipped with a pawl-rack transport system sometimes followed by rollers, in this case, however, the baskets follow a circular path.

Inlet nozzles – Just before the machine entrance, there may be nozzles that wet fresh water on the dishes before they are introduced into the washing modules, in order to eliminate the coarsest food residues before entering the dishwasher, without contaminating the tank and risking the clogging of the filters.

Entrance washbasin – It is possible to have a washbasin on the straight section where the operator performs a first rough cleaning of the dishes before they are conveyed inside the dishwasher.

Curiosity

The name “carousel” comes from the movement of the baskets that recall the amusement ride for children.

Elframo carousel dishwashers

Elframo offers customized carousel systems according to the needs of each customer. Our washing solutions are designed entirely by our internal R&D department.

Are you looking for more information? Contact our sales department and we will support you in choosing the most suitable dishwasher to meet your needs.