Waste of Transportation
Waste of transportation can involve raw components, sub-assemblies, empty boxes or just about anything that is required for production. It will not only be found in the production area, but also the material delivery areas, throughout the supply chain and even in offices. Transporting material is a necessary activity but it doesn’t add value to the end product. Eliminating or reducing this type of waste within your facility (or within your supply chain) may reduce overall lead time or cycle time.
Within the production area, waste of transportation will be found when product is not stored close to the point of use. If space allows (based on component sizes), keep a small store of inventory near the production area. This will avoid having to bring the product back and forth to a warehouse.
When using the components, they should be at the station where they are being used. Any distance further than an arms length away is considered a waste. Look for ways to store the components in use close to the worker whenever possible. When you do get them closer to the worker, continue looking for improvements by eliminating unneccessary motions (parts stored in the proper position on the correct side of the worker).
Material Delivery Areas
Waste of transportation will be more evident in the material delivery areas than the production areas. Moving product further than necessary, storing product in a temporary location only to move it shortly thereafter and moving with empty delivery carts are all considered a very big waste. Application of standardized material handling routes will help reduce this waste.
As part of the route, the delivery person will travel only with a full cart; component delivery one way, empty totes the other way (assuming returnable containers are used). By doing this, the person transporting the parts will never travel with an empty cart which is considered a huge waste in lean manufacturing.
The basic concept is as follows; for every full box of components delivered (using a kanban system), an empty box should be available to be returned to the supplier. With every box of finished goods picked up, an empty box will be required by production.
Although transportation plays a major part in the Supply Chain, careful consideration must be taken to reduce it whenever possible. Optimizing your transportation is another viable option through use of methods such as “milk runs”. This involves picking up product from multiple suppliers on a route. The following example shows a situation where improvement opportunities are abundant.
A manufacturing company has two facilities. All materials for both plants are received at one facility, we’ll call it plant A. Resin, a material used to mold plastic parts, comes into plant A but is used at plant B (the main plant for manufacturing plastic components). The resin is shipped to plant B. The resin is used to mold parts that are primarily used at plant A. The molded parts are shipped to plant A. The parts are built into a finished good that is married up with product at plant B. The part (contained within a finished product) is shipped back to plant B.
As you can see, this is a well travelled component and there is much waste of transportation here. A couple of improvement opportunities stand out. First, resin could be received at plant B. This would eliminate one trip for the resin. Second, the parts could be molded at plant A. This would eliminate 2 trips, one for the resin and one for the molded part.
Regardless of the choice that is made, you must continue to make improvements to the transportation within your supply chain in order to remain competitive.