The hidden costs in cold room operations

Citation

(2001), "The hidden costs in cold room operations", Industrial Robot, Vol. 28 No. 3. https://doi.org/10.1108/ir.2001.04928caf.001

The hidden costs in cold room operations

The hidden costs in cold room operations

Keywords: Robots, Food, Hostile environments, Fanuc

The growth of the frozen foods and the ready meals markets means that more people in the food industry are going to spend more time in a sub zero environment. Apart from not being the most pleasant environment it is also expensive.

When compared with handling products at normal room temperature, four areas of either additional costs or possible cause for concern can be identified:

1. 1.

   Less Productive staff. The Health and Safety Executive in the publication Health and Safety in Retail and Wholesale Warehouses make a number of recommendations that would inevitably lead to staff being less productive. While the H&SE reasoning is irrefutable, it is nevertheless a cost burden for employers. Although it has to be said their guidance is less than precise. In fact, even after speaking to several local inspectors it was difficult to get a definitive answer. The guidelines say "Suitable and sufficient breaks should be arranged for cold store operators so they may warm themselves". What is "suitable and sufficient" is open to interpretation. One suggestion was at least five minutes every hour out the freezer. That is effectively a 10 per cent labour on cost. Others talk about 20 minutes outside every two to three hours. There appears to be no hard and fast rule. But, what ever figures you take, its not the most productive use of labour. However the guidelines also recommended that if any worker suffers "physical discomfort" then a period of approximately 20 minutes at 20°C with outer clothing removed is necessary in order to fully recover.

2. 2.

   Rotation of staff. One method of countering idle time outside the cold store is to rotate staff between jobs inside and outside the cold store. This looks good on paper but in practice during the changeover there is inevitable time wasted as operators finish the task in hand before changing. What tends to happen is one set of operators find a natural break in the work, then move to the other area and wait for the others to reach a similar position.

3. 3.

   Clothing and other protective measures. There's a obvious cost involved in the initial purchase of thermal clothing, but it doesn't stop there. Storage and cleaning are other factors in the equation.

4. 4.

   Medical risks. Cold exposure causes physiological effects which may be harmful to those with cardiovascular disease. Particular care should be given to assessment of the following conditions:

5. 5.
   • •

     cardiac disease;

   • •

     hypertension;

   • •

     peripheral vascular disease;

   • •

     respiratory disease;

   • •

     thyroid or other endocrine disease;

   • •

     rheumatic or musculoskeletal disorders.

   In addition many prescribed drugs and alcohol may impair thermoregulation of the body in the cold. These include anti-depressants, tranquillisers, hypnotics, drugs of abuse, hypoglycaemics, anti-thyroid drugs and sympathetic and ganglion blocking agents.

   From this it follows that where a medical examination is performed on cold store personnel a full clinical examination should be made. Special tests such as electro-cardiography or lung function testing should be undertaken at the discretion of the occupational physician.

It was to address these concerns that Fanuc Robotics developed a special version of the M410i. This is a palletising robot for sub zero environments, down to –30°C. Automating the palletising and reducing the requirement for people in the cold room has obvious attractions (see Plate 1).

To adopt the robot for the cold room environment, the robot mechanism is enclosed in insulated sleeves through which warm air is circulated. The control system is located outside the cold room, while the "teach pendant" that is used inside the cold room to create programs is held in a heated’bag.

Plate 1 The M410i developed by Fanuc Robotics

The only other concession to the operating temperature may be if gripping forks are used at the end of the robot arm. In a more conventional environment, these would be pneumatically actuated. Compressed air can contain moisture, to eliminate potential problems caused by frozen and blocked air lines, the fork grippers should use electric linear actuators. In all other aspects it is a conventional palletising robot.

In all other aspects the cold room robots are identical to those used at normal room temperature. The maximum load capacity ranges from 100kg to 400kg. Even the robot with the highest capacity operates at high speed.

It can perform up to 730 standard cycles/hr. A standard cycle comprises a 400mm lift, 2,000mm horizontal traverse followed by 400mm down. With such a lifting capacity, it is the ideal solution for "complete layer" lifting of cases of bottles and food stuffs.

The robot follows the same configuration of other Fanuc palletising models with an over hung arm. This means the robot always accesses the in-feed conveyors or pallets from the upper surface. With a general purpose articulated robot there is always the risk of collision with the front of the pallet, when reaching to the back. The Fanuc M410i configuration eliminates this possibility.

Using the 360° rotation on the base or J1 axis, one robot can service a number of in-feed and palletising stations. Pallet envelopes can be 1,600 x 1,600mm square by 2,100mm high, alternatively higher 1,300 x 1,300 square by 2,450mm high pallets can be configured.

The robot can utilise the Fanuc Pallet Tool software that allows the operator to optimise palletising patterns based on the pallet size and box size. A graphical user interface enables the operator to review stacking options without any specialised programming knowledge. These can interlock cases for maximum stability.

It is worth bearing in mind that robot palletising has made major in-roads in the food industry at conventional room temperatures where the additional costs outlined are not incurred. It is fair to say that many current users initially investigated robot palletising under duress as a reaction to the H& SE regulations on manual lifting of loads.

It came as a pleasant surprise to many to find the robot palletising could be economically justified on the basis of the technology alone. Conforming with the manual lifting regulations was an added bonus. Perhaps there is a similar surprise in store for cold room operators.