The fastest automatic assembly with the highest quality standards in the world
Anest Iwata operates its own automatic pump assembly system called “RYOGA”. Can you tell us something about the background of RYOGA?
Anest Iwata's oil-free scroll compressor has become a global standard since its introduction in 1991. The scroll pump is a precision machine that has very low tolerances. Initially, we relied on the craftsmanship of our dedicated factory staff. The quality of the pump was a direct reflection of their professionalism and artistic sense. Japan was changing as we grew, and so we had to recognize the sad reality of the country: Our population was shrinking. The workforce in our industry was also dwindling. When a big order came in, we had to send all the employees to production. That meant people were working on the production line who normally did desk jobs. Unfortunately, this led to some rejections. Among our commitments to our customers is a lead-time policy that says, "Ordered today, shipped today." In order to keep this promise while maintaining pump quality, we had to depart from our traditional mindset and implement an automated production system that reflected the craftsmanship of our employees. Pump no. 1 and pump no. 2000 must be exactly the same. RYOGA was designed and installed with this mission and commitment.
A long time ago, the quality of scroll pumps was based on the craftsmanship of the factory workers. What were the challenges you faced while building an automated system?
A lack of precision during production leads to a lack of functionality of the end products. This is true for any type of production. The oil-free scroll compressor reflects this theory most directly. The assembly of the two spiral windings is one of the typical examples. The accuracy of the positions of these coils is studied in microscopic measurement. It allows only a tolerance of a few micrometers. The determination of the tightening torque of the screws and the detection of a deformation of the parts are the typical methods for the correct adjustment. Before we installed our automated system, these adjustments were made manually by our factory staff, relying entirely on their experience. We basically had to copy their brains into RYOGA. The most difficult part of the transition was transforming the manual assembly process into an algorithm. Previously relying on the feeling and experience of skilled hands, it was now transformed into an automated system. To achieve this, countless unique formulas were created for each assembly step. Creating a program based on these formulas and determining reliable values to predict natural production variables was a long and daunting process. But we had to carefully execute each step, because our production includes tens of thousands of pumps. The spiral motion of the scroll is generated by a central crankshaft and three auxiliary cranks with pins. Adjusting their alignment was extremely difficult. Our factory workers relied on the feeling in their arm for alignment. "Alignment" is one word, but it involves several different jobs. Inserting the auxiliary cranks into their respective bearings, precisely aligning each crank with the central crankshaft, and gradually turning the pump - this was the most difficult process to transfer to the automatic system.
What remarkable changes did the introduction of RYOGA bring ?
2020 was a challenge for everyone because of the pandemic. We had to say goodbye to our traditional habit of relying on the availability of manpower. Without RYOGA, it would have been very difficult for us to fulfill all orders last year. The automated system, supported by our experienced staff, has brought our quality to a new level. We will continue to work with full commitment to provide the most reliable scroll pump to each of our customers.
*This statement is based on our own study of industrial oil-free scroll compressors with a capacity of more than 0.75 kW.