Manufacturing - machining

Where it all began.

In the 1970's factory layouts had started to change from functional layouts to flow layouts but machines were mainly manually loaded due to the fact that the machines were designed that way.

Machine operators had a buffer of unmachined parts before the machine (time buffer) and a buffer of machined parts after the machine (space buffer).

These buffers were often in the form of a tray or a basket on wheels with a predefined number of parts which was transported by the operators to the next machine in the process.

The issues

These systems worked reasonably well but there were a number of issues that needed to be addressed.

• Having one operator per machine was not efficient but machines were hard to load automatically.
• Manual handling of parts caused small and hardly detectable damage to the parts which would later appear as noise in the finished product.
• Every machine had many different operators which meant that the quality of a process was not constant.
• The handling of baskets and trays created inventory which was difficult to control and monitor.
• The amount of inventory made it impossible to achieve a high FIFO level which in turn had a negative effect on quality as parts were not machine in sequence but rather random

Quality and Performance

As the quality demand and performance of the final product increased, the requirements on the individual part increased even more. Even defects that could not be detected by the human eye was causing problems in the final products.

It became obvious that all of the issues had to be solved in order to be able to maintain a guaranteed level of performance. The only way to eliminate these issues was the make the processes more stabile and that had to involve a higher degree af automation.

The first task was to convince machine tool manufacturers to redesign the machines for automatic loading while still giving operators a possibility to supervise, monitor and service the machining process.

The second task was to find a way of handling parts between the machines in a way that would eliminate all the remaining issues and that handling process had to be 100% reliable year after year.

Evolution of lean conveying automation

In a close cooperation with Volvo, EWAB invented and developed the necessary principles and equipment to solve the safe and efficient handling of parts between machining operations in a very harsh environment with chips, grinding particles and coolant.

Other companies in the car industry had similar needs but much higher volume requirements which was leading to new challenges involving multiple flows with flexible routing within the same system, for different parts being machined at the same time while maintaining 100% traceability.

Today

Today EWAB Flow Technology includes one-piece-flow solutions for components from 0 - 1500 kg. Takt times is seldom shorter than 10 seconds but there are systems that run at a Takt time as low as 3 seconds.

The system with baskets, trays and alike have recently returned as an invention - obviously without knowing that this approach was tested and rejected in the 1970's