Automation – Load and Unload

This series of blogs about automation will address automation as an “add-on” or accessory to an existing or planned cleaning system.  In many cleaning systems, automation, or at least partial automation, is an integral part of the system as it is required for effective cleaning process.  This is especially true of spray washers which often rely on part rotation to allow spray access to all surfaces of the part(s) being cleaned.  But even with systems which already have automation, adjuncts like conveyors and lift tables can be added to facilitate or simplify material handling.

Load and Unload Locations

One of the basic considerations for an automation system is where the parts will be picked up and where they will be delivered.  Depending on circumstances, load and unload stations can be arranged to facilitate the flow of parts through the manufacturing process – as long as the parts are being moved anyway, why not utilize the move to your advantage?  For example, in some instances, it may be best to have the load and unload stations immediately adjacent to one another to eliminate the need for a single operator to walk from one end of the machine to the other to load and unload parts.  In the case where there are two operators, however, delivery to a downstream location may be a desired feature.  One example of this might be when cleaned parts, once cleaned, are delivered directly into a clean room or packaging area.

To assure uninterrupted process flow, it is often beneficial to provide a conveyor at the load and/or unload positions capable of queuing 20 to 30 minutes of production ready for cleaning or transfer to the next step.  This is usually accomplished using either a simple gravity conveyor or a powered conveyor with sequencing capability.  When space is limited, load and unload conveyors can be positioned perpendicular to the flow of parts through the system to reduce the length of the overall machine.

Other considerations for the load and unload stations might be a lift table or hoist in the case of large or heavy parts or a demagnetizer for parts which might hold residual magnetism from the manufacturing process.

One thing that is often overlooked in the design of automation is that parts baskets or fixtures used to process parts through the cleaning process need to be returned to a location prior to cleaning for reloading once emptied.  In a high volume cleaning operation, a secondary conveyor might be used to return baskets from the unload end of the machine back to the load station or another point prior to cleaning.

Although the above considerations may seem trivial, they provide the starting point in the design of an automated cleaning system.  Just as important (but more obvious) are knowing the exact cleaning process as well as the required system throughput in terms of the number of baskets or fixtures of parts to be processed.  In the next several blogs I will describe a number of automation options along with their benefits and shortcomings.

–  FJF  –