Waste of Waiting
Waste of waiting can be found in many forms. It can be very obvious in some situations, yet very difficult to see in others. Some of the more obvious forms of waiting will be evident when there are component shortages on a production line, or when a machine is down. Waste of waiting may be a little more difficult to notice within a process, as it may be overlooked or considered “necessary”. Whatever the case, this waste, like all other waste, must be identified and eliminated.
When a line or production area encounters a part shortage, it is very easy to see that people are standing around waiting for the parts to arrive. This type of event will usually draw much attention and get highlighted quickly. The cause of the shortage must be addressed and countermeasures put in place to prevent this idle time.
There are two basic scenarios for parts shortages; parts are in the plant and not delivered (not in the place required as required) or, parts are not within your facility. If parts are in the plant and were not delivered when needed, you will need to address your parts delivery method. Standardized material handling routes and a kanban system will help reduce or eliminate these types of problems.
The other scenario, parts not in the facility, can be even more damaging. Unavailability of parts can cause vast amounts of downtime and add huge expense trying to expedite parts into the building. In this case yourmaterial planning methods will need to be reviewed as well as your inventory accuracy. This type of waste can lead to missed shipping deadlines which will hurt your delivery rating and damage your company’s reputation.
Another obvious area in the waste of waiting category is machine downtime. If a worker is at a machine that is not functioning, parts are not being produced. If the proper skill level person does not reside within your facility to fix the machine, the worker will be idle for a long period of time. The proper spare equipment and a solid preventative maintenance program will help to greatly reduce the incidents of machine downtime. It may also shorten the duration of these events when they do occur.
The last area to review, and sometimes most difficult to identify, is wait time within the process. The most effective way to start identifying waste in the process is to implement standardized work. Through the creation of standardized work, it will be very easy to identify any wait time. Without standardized work, the worker may do things differently each time and mask the problem. This is when it becomes difficult to identify the waiting time.
A worker standing at a machine waiting for it to process is considered waste of waiting. Some may argue that the person can not proceed until the machine is finished cycling. This may be true if the operator is only responsible for that machine, however by making the operator responsible for more than one machine, the time spent waiting can now be utilized on the other machine.
For example, an operator is working on the first machine. Two components are put together and put into a press. While the machine is cycling the operator can remove the part from the next machine, pass it to the next operation (if applicable), prepare the necessary parts for the second press and cycle this machine. During the cycling process of the second press, the operator will go back to the first press which may now be finished cycling. This will eliminate the wait and make the operator more productive.