table k Force application factor according to tab B4CH-14-C Bevel-helical speed reduction gearboxes B4

Flender/Flender Gear Units/Bevel-helical speed reduction gearboxes B4

that increasing theamount of vent surface on container by over 6% of the side surface results in decrease in the strength of the container. Therefore, careful selection of containers is necessary (. Reusable plastic containers allow up to 4% of the side surface of the containers tobe used as vents. However, an opening percentage of 2% seems to be the optimum,taking into account cooling efciency and physical support the container provides to theproduce (. Since the cooling rate is affected by the velocity of the air (, proper fanselection is required to obtain the ow rates mentioned. This method of cooling requiresgreater refrigeration capacity than room cooling because of the higher rate of heat removal. It also requires fans that have the capacity to deliver the required ow rate at the ideal pressure. Forced-air cooling is very attractive to small operations that harvest many types of produce, as it is suitable for wide range of produce. It is believed that forced-air coolingcan dry out some products, such as lettuce, spinach, mushrooms, and peaches. However, 5 Rennie et al. forced-air cooling of these products can be successful if the cooling is rapid and the relative humidity of the air is kept high (. Forced-air tunnel systems are the most used form of forced-air cooling. Two rows of palletized containers are placed parallel to each other with space between them (Fig.. The aisle formed is covered on the top, along with one end to create tunnel. fan is placed at the free end to pull the air out of the air plenum tunnel, creating static pressure difference across the containers. The cooled air around the outside of the palletsis pulled through the produce and into the plenum by the pressure difference. The costsassociated with this type of forced-air system are minimal. The fan may be portableunit that returns the air to the room or permanent fan that directs the air back directlyto the cooling coils. In the case of the portable fan, the warm ai