Food processing machinery - Food depositors - Safety and hygiene requirements
|Publication Date:||1 April 2021|
|ICS Code (Plants and equipment for the food industry):||67.260|
This document deals with all significant hazards, hazardous situations and events relevant to food depositors as listed in 1.2 and the equipment typically integrated with them, i.e. product pumps, product elevators, conveyors and indexing mechanisms, when they are used as intended and under conditions of misuse which are reasonably foreseeable by the manufacturer (see Annex B).
This document deals with the significant hazards, hazardous situations and events during transport, assembly and installation, commissioning, use, decommissioning, disabling, dismantling and scrapping.
NOTE 1 According to the clause which is referred to, "use" includes "setting, teaching/programming
NOTE 2 Although this document is intended to apply to depositors used in the food industry, many of its requirements can also be used for the same or similar machines used in other industries.
This document is not applicable to the following machines:
- auger depositors or auger fillers and gravimetric filling machines, safety requirements for these machines are contained in EN 415-3;
- automatic dough dividers, safety requirements for these machines are contained in EN 12042;
- filling machines for sausages, safety requirements for these machines are contained in EN 12463;
- mincing machines, safety requirements for these machines are contained in EN 12331;
- food depositors that are powered exclusively by manual effort.
This document does not deal with the following hazards:
- hazards related to the use of food depositors in a potentially explosive atmosphere;
- hazards that may arise from using a food depositor to deposit a non-food product.
This document is not applicable to food depositors that were manufactured before the date of its publication as a European Standard.
Types of food depositors
This document deals with five different types of food depositor. The component parts of each of the different types of depositor are labelled in the figures shown in Clause 4 of this document.
A piston depositor typically comprises a hopper, a rotary valve, a product measuring chamber in the form of a piston and a product dispensing valve. Some piston depositors incorporate several product measuring chambers and dispensing valves. Some designs dispense the product directly from the rotary valve without the use of a separate product dispensing valve. The volume of product dispensed is varied by altering the stroke of the product measuring chamber piston. Piston depositors are used to fill liquids, liquids containing solids in suspension and pastes. The product dispensing valve may be attached rigidly to the depositor or using a flexible pipe and in some cases is held by the operator. Figure 1 shows the typical cross section of a piston depositor.
A chamber depositor comprises a hopper feeding one or more product measuring chambers that are filled under gravity from the top. When the chamber has been filled with product the flow of product is stopped either by moving the chamber or using a product cutting device. The product is then discharged through the bottom of the chamber either by moving the chamber or by moving a plate in the base of the chamber. The volume of product dispensed is varied by altering the volume of the chamber. Chamber depositors are typically used to deposit free-flowing products like cooked rice or pasta. Figure 2 shows the typical cross section of a chamber depositor.
A roller depositor typically comprises a hopper that feeds product to two or more fluted contra-rotating rollers. These rollers force the product through one or more dies that shape the product. The product is then separated using a product cutting device like a wire cut mechanism. On some designs of the machine the dies are moved while the product is dispensed to produce a shaped product. The volume of product dispensed is varied by altering the timing of the product cut-off device. Roller depositors are typically used to deposit dough or confectionery products. Figure 3 shows the typical cross section of a roller depositor.
A pump depositor comprises a hopper that feeds a pump which in turn feeds pipe-work on which are mounted one or more product dispensing valves. The dispensing valves may remain fixed, move up and down or from side to side in synchronization with a product conveyor. The volume of product dispensed is varied by altering the length of time that the dispensing valves are open. Pump depositors are typically used to deposit liquids or liquids containing finely divided solids. Figure 4 shows the typical cross section of a pump depositor.
A screw depositor comprises a hopper in which a screw is mounted. When the screw rotates it draws product from the hopper into a pipe. The hopper may be equipped with stirrers to move the product towards the screw and a product measuring chamber or product dispensing valve may be fitted to the discharge of the screw. The volume of product can be varied by increasing or decreasing the speed of the screw, by varying the volume of the measuring chamber or by controlling the actuation of the product dispensing valve. Screw depositors are typically used to deposit dough, pastes or creams. Figure 5 shows the typical cross section of a screw depositor.