No matter how good is the method that is used to
transform a product, it would be pointless if we do NOT have a method to govern
the movement of the product in the production floor from one process to another
process. Although transportation does
not transform the product however it could potentially induce defect to the
product mainly dent, broken, component or part being knock off for PCBA
etc. Moving parts from one work station
to another station is also a process. Like
any other process, transportation of parts have input and output. Most of the manufacturers had neglected this
point. Having conducted audit in more
than 100 suppliers from Asia to North and South America, almost all manufacturing sites had audit findings
related to transportation and handling of the parts in the production
floor. We shall put our focus on manual
process as parts transfer for manual process has more variation compare to automated process.
We will focus on 2 important elements in transportation, a
place to hold the part and vehicle use to move the parts.
A good transportation method should have the following criteria
at the minimum:-
Place
to hold the parts
- A well design storage medium such as tray which minimize part handling, easy to maintain. And clean to store the part during transportation. Best practice would be point of use storage system which do not need any repackaging or sorting.
- Convenient for operator to transform the parts, does not have complicated bag or seal bag where operator need to spend time to get the part out.
- Able to protect parts from transportation damage and accidents
- Regular checking and cleaning of the storage medium.
- All storage medium should be having an individual ID for tracking purpose.
- Made from durable material and must strong enough to hold the parts and suitable to use for the type of part such as ESD compliance for ESD sensitive device. Prefer recyclable material.
- Clear identification on storage tray on the process steps of the parts eg. before and after testing
Vehicle
to transport part
- Vehicle size such as weight height that is suitable and ergonomic friendly to operator. Ensure part is not stack too high to prevent falling.
- Vehicle has design to protect part such as ESD compliance for ESD sensitive device and protective shock absorb pads
- Vehicle must have ID and have preventive maintenance system to ensure vehicle is in good condition
- If conveyor belt is used, it must also be cleaned and maintained to ensure smooth running.
Various trolley which can used to transport part in production floor |
It is not encourage using bulky wrapper which is
difficult to clean, wrapper can only protect part during transportation and most
handling could be induced during the actual manufacturing. This does not make good return on investment
sense. Most the bulky wrapper which I
have come across is difficult to clean and operator had to waste time to put
part into the wrapper. No matter how
good the part is protected in a bulky wrapper, we still need to bring the part
out for further processing.
Example of bulky wrapper |
In lean manufacturing, it is prefered all transformation
process close to each other in U shape configuration continuous manufacturing
line with one piece flow. This type of manufacturing line would prevent
unnecessary transportation and fit very well in assembly process. In this way we would minimize/prevent variation
created by long distance transportation within manufacturing entity. This type of process will reduce variation
and serve the purpose of design a process input to produce consistent good
quality products.