"The best in the world" of scroll

APPRECIATION We thank you for your 30 years continued patronage

Two years after the debut of the World’s first Oil-free Scroll Compressor,
Dry Scroll Vacuum Pump was brought out
as another first-in-the-World’s from ANEST IWATA.
It’s well accepted and shown remarkable growth together with a sibling,
we are now celebrating its 28th anniversary.

The world's first Dry
scroll vacuum pump

ANEST IWATA introduced, the first in the world “Dry (=oil-free) scroll vacuum pump” in 1993. It offered numbers of advantages compared to vacuum pumps with conventional technologies, such as compact in size, providing better ultimate pressure, quieter and less vibration while it was running and with a energy saving feature. To date, dry scroll vacuum pumps have been well accepted in all the industry, such as physics and analytical equipment, semi-conductor processing, automotive and aerospace experiment. Fundamental concepts were close between air compressors and vacuum pumps, however, they were not the same as engineers thought in the first place. As the development project was started from the scratch, engineers encountered so many difficult situations at almost every developmental stage because it was “the First in the World’s Dry Scroll Vacuum Pump” Then-project team member Masaru Tsuchiya, who is a current member of Vacuum Equipment development group, spoke about the story.


ANEST IWATA introduced the world's
first oil-free scroll vacuum pump in 1993,
two years after its introduction
of the scroll compressor.
Please tell us what made ANEST IWATA
decide to start the vacuum pump development.

In 1980’s, we were seeking new businesses other than existing spray equipment or air compressor industries. While the compressor development team begun the project with oil-free scroll technologies, our team thought out it should also work as a vacuum pump. Both projects were simultaneously started but progressed separately. As a result, we, as a vacuum pump development team, spent approximately five years until introducing the first-in-the-world Dry Scroll Vacuum Pump .

Vacuum Development Group Masaru Tsuchiya
Vacuum Development Group Masaru Tsuchiya

Please tell us what was the most elaborated
time and process during the development.

At first, I’d like to explain the difference between air compressors and vacuum pumps.Compressors intake atmospheric air and compress multifold to raise the pressure. On the other hand, vacuum pumps “reduce pressure” of inlet and a sealed container connected to it, which means the pump makes vacuum by catching and removing numbers of gas molecular from the container.
We adopted the same scroll principle but physical stress to the pump bodies were different, because of one worked for compression to raise the pressure, while the other was pumping out to reduce it. In other words, function and strength on components are different between compressor and vacuum pump, as we studied we found their behavior were also different.
Many components looked like the same but we needed to test then study and re-invent almost of all items, made them fit to the vacuum application.For example, we explored new seal material, which we saught certain strength and repulsion because it should work in the range of atmospheric pressure and the hundred-thousandth of it.

The operating status of ISP (Dry scroll vacuum pump)

The amazing Scroll

01 First Development
in the world

Let's hear what the pioneer of the scroll technology has to say about his experience.Mr. Sato Kazuaki, who sits as an engineer at Anest Iwata's advanced technology lab will tell us what he saw behind the scene, from day one of the project to this day.

The scroll development project team (1986)
The scroll development project team (1986)

What was in your vision when the company choseto develop a Scroll compressor? Why the Scroll Mechanism was chosen above all others?

Back in that time, an oil free compressor was not a choice for a common industrial application. It was because of the higher price, limited functionality and the poor durability. Anest Iwata was still determined to invest in Oil Free, to stand out in the competition. Having the Oil Free as our goal, we had some challenges to work on, because we wanted our product to provide something different. It had to be quiet, low vibration and small. Scroll's development has started becaue it presented more potentials than any other pumps commonly used back then. When the project started we saw scroll only as a valuable "option". At that time we even didn't realize its true potential. As we studied the mechanism deeper, more convinced we were that the scroll was the answer. First of all, there is no oil in the oil free machine. For this reason there are only two choices left on the selection of the sealing material. They were non-contact seal that works in a very tight clearance or, a durable contact seal. Each presented more challenges to manage; with the non-contact seal the air leakage from the clearance and with the contact seal, the deterioration on the seal.

①Leakage from circumferential gap
①円周方向隙間からの漏れ ①円周方向隙間からの漏れ
As the orbiting portion of the scroll move against the fixed portion, it creates multiple crecient-moon-shaped air pockets accompanied by multiple non-contact sealing lines on the right and left of the pump. The clearance on each sealing line is about the space of a hair. The incoming air traveles through an increasing confined space and finally achieves to the center. Pressure differencial between the air pocket is kept minimal which contributes to a stable compression.

How did you tuckle with all the challenges?

There was nothing much we could look up back then, so basically we were taking our steps almost blindfolded. Generating the orbiting motion which is unique to the scroll was the hardest challenge of all. Back then it was considered unachiavable with oil free machine but we made it to give a birth to it, because we invented the world first precision Pin-Crank mechanism. We've added another key step on our process to adjust the clearance of the scroll. These two were the most significant milestons that we ever established on the path of Oil Free. Next step was the tip seals. Tip Seal is a contact sealer and its primary job is to trap the pressurized air. With the oil free pump where oil seal is absent, we had to go through many different materials. Most of them gave only poor results and worn out quickly. To improve both the functionality of the seal and efficiency of the compression, we created tons of proto types. When we felt that we've exhausted all the options and ideas, we came up with an idea to provide small cuts on the seal which we call now "Lips". They were made on the side and on the bottom of the seal, only few milimeters apart. As compression started, the lips stood up just like fish scale. It is because of the pressure difference between the lips. After this achievement the sealing effect was drastically improved and the Tip Seal has proven its compression efficiency. The problem about wear and tear of the material, we worked closely with the supplier of the seals. We've gone through many durability tests together and throughout this testing phase, we have developed several proto-types using with different types of resins. We have studied each cases to seek the optimum roughness on the surface. The durability tests were performed in harsh condition many times. After all of these tests, we achieved 10,000 hours durability.

②Swirling motion
③Tip seal with the lip
リップ付チップシール リップ付チップシール

What was the most difficult part in this project?

If I pick the hardest challenge, it was the deadline. Initial time frame we were given for the project had long gone by, and we were counting 5 years since then. At that time we were almost ready to bring the production of the scroll to the commercial level however, from engineering stand point there were some uncertainty that I could not ignore. We were faced by the second deadline and we had to make a decision. Our project team discussed many times and at the end we opted to extend the project for another year. We had evaluation after evaluation, resolving all the challenges each time and took our step forward one at a time. It was great we could take our time for evaluation because no customers complained about the functionality of scroll after they took off to the market. Our products proved its value and gained the trust from the customers.

Statement is based on our own study on the industrial oil free scroll compressor larger than 0.75kW

佐藤 和昭
Sato kazuaki

02 GLOBAL SUPPLY World Top Production Unit Sales

Ever since the world first scroll compressor was launched in 1991, Anest Iwata has been maintaining the top market share for the past 30 years. As shown in the graph the sales have grown steadily and we've finally achieved the total sales of 550,000 units.We've established our presense in the major cities of the world and our sales offices and production centers can be found in Europe, North & South America, China, Korea, and South East Asia as shown in the map. We will continue striving to support our customers and ensure smooth distribution of the scroll compressors in conjuction with Anest Iwata in the world. Taking this opportunity we would like to express our gratitude to our loyal customers. We walked together for 30 years and for the more years to come, we will renew our commitment for the further improvement to gain your trust even more.

Statement is based on our own study on the industrial oil free scroll compressor larger than 0.75kW or, the industrial oil free scroll vacuum pump, larger than 0.1kW.

累計生産販売台数の推移 累計生産販売台数の推移
エリア別生産販売規模 エリア別生産販売規模

03 RYOGA World's fastest automatic assembly / World's highest quality

Anest Iwata's own automated pump assembly system "RYOGA". Tell us some back groundstories behind RYOGA

Anest Iwata's Oil Free Scroll compressor has become one of the world standard ever since it was launched in 1991. Scroll pump is a precision machine which yields very low tolerance. Initially we relied on the craftmanship of our dedicated factory members. The quality of the pump was the direct reflection of their professionalism and artistic sense. Japan has changed as we grew, and we had to realize the sad reality of the country, our population has been shriking. Work force in our type of industry was also becoming smaller. When a massive order came through, we had to send all the hands on the deck. This means there were people in the production line who usually sit on the desk. Unfortunately this caused some rejections. As our commitment to our customer, we have a policy on the lead time. "Order today, ship today" is one of them. In order to keep this promise while assuring the quality of the pump, we had to depart from our traditional way of thinking.Instead of relying on the people, we had to establish an automated production system that mirrors the craftmanship of our fellow factory members.Pump #1 and Pump#2000 need to be equal and identical.RYOGA was designed and installed with our missions and commitment like that.

Long time ago the scroll pumps' quality relied on the craftsmanship of the factorymembers. What was the challengesyou went through while building an automated system?

A lack of precision during the production leads to a lack of funcitonality of the end products. This applies to any type of production. Oil Free Scroll Compressor reflects this theory most directly. The assembly of the two spiral wraps is one of the typical examples. The accuracy of the positions of these wraps are examined in the microscopic measurement. It allows only few micron-meter tolerance. Determining the torque of the bolts and detecting a deformation of the parts are the typical method for the proper adjustment. Before we installed our automated system, these adjustment was done manually by our factory members, totally reling on their experience. We basically had to copy their brain into RYOGA. The hardest part of the transition was converting the manual assembly process into an algorithm. It was once relied on the feeling and experience of the skilled hands, now coverted into an automated system. To achieve there, uncountable numbers of unique formulas were created for each assembly step. Creating a program based on these formulas and coming up with some reliable values to predict natural production variables were a long and daunting process. But we had to take every single step diligently, because our production is counting tens of thousands of pumps. Scroll's sprial motion is generated by one central crank shaft and three pin-auxiliary cranks. Adjusting their alighment was extremely tough. Our factory members used to rely on the feelings on their arm to align them. "Alignment" is one word but it contains several different work. Inserting each auxiliary cranks into the respective bearings, matching the orientation of each crank exactly the same as the central crank shaft while turning the pump gradually.This was the most difficult process to copy into the automatic system.

グローバル生産戦略部 穂積 寛之
Global Production strategy Department Hiroyuki Hozumi

What is the notable changes after RYOGA implemented?

2020 was challenging to anyone due to the pandemic. We had to depart from our traditional habit to rely on the availability of human workforce. It would have been very tough for us to respond all the orders last year, had it not been for RYOGA. Automated system backed up by our experienced team member brought our quality to another level. We will continue to strive to deliver the most reliable scroll pump to each one of our customers.

Statement is based on our own study on the industrial oil free scroll compressor larger than 0.75kW

04 LINEUP The widest lineup
in the world

As scroll compressor made its way to the world market, the demand of the larger equipment and higher pressure models have grown. To respond such demand and the expectation, we have been constantly updating our lineups to this day. In 1993, Anest Iwata's dry scroll vacuum pump was launched for the first time in the world. The range of the capacity is keep expanding since then. Ever since the scroll compressor pump was launched, we have been striving to achieve higher capacity. Along with the further development of our scroll pump, we have been improving the functionality of the multi-unit construction models. We will continue expanding our line up while maintaining the originality and usability in our mind.

Statement is based on our own study on the industrial oil free scroll compressor larger than 0.75kW or, the industrial oil free scroll vacuum pump, larger than 0.1kW.

Scroll Compressor Air End

(0.75kW-7.5kW, 0.8MPa and 1.0MPa, 8 models)

Model Motor rate
Max. operating
bar psi
SL-105EF 0.75 8 116
SL-140EB 1.5/2.2 8/10 116/145
SL-165E 3.7 8 116
SL-1651E 10 145
SL-205 5.5 8 116
SL-2051 10 145
SL-210 7.5 8 116
SL-2101 10 145

Scroll Vacuum pumps

Pumping speed (50L/min - 1,000L/min)

Model # Ultimate
Pumping Speed
Motor rated
L/min L/min m3/h m3/h
Pa mbar Torr 50 Hz 60 Hz 50 Hz 60 Hz
ISP-50 10 1.0 x 10-1 7.5 x 10-2 50 60 3 4 0.1
ISP-90 5 5.0 x 10-1 3.8 x 10-2 90 108 5 7 0.15
ISP-250E 1.6 1.6 x 10-2 1.2 x 10-2 250 300 15 18 0.4
ISP-500C 1 1.0 x 10-2 7.5 x 10-3 500 600 30 36 0.6
ISP-1000E 1 1.0 x 10-2 7.5 x 10-3 1000 1200 60 72 1.4
DVSL-100C-B 50 5.0 x 10-1 3.8 x 10-2 100 120 6 7 0.3
DVSL-500E 30 3.0 x 10-1 2.3 x 10-2 430 516 26 31 1.1

05 SILENT Silent Compressor

World quietest compressor pump

Oil Free scroll compressors come with many unique characters. Its quiet operation is one of them. The torque fluctuation is minimal and this is a direct contribution for the quiet operation. Amoung all the competitors around the world, Anest Iwata's scroll takes the seat in the top group. We are very excited to announce our new model joining the existing line up this year. This will be the ultimate model in the noise reduction. Scroll Compressor is reaching 30 years milestone and, as we continue going forward, scroll is continue evolving.

Statement is based on our own study on the industrial oil free scroll compressor larger than 0.75kW

06 ENERGY SAVING The world highest
energy efficiency

Excelence in the control system Generating value when pump stays inactive

Multiple pumps mounted in a compressor units turns on and off independently. This control method responds most efficiently to the fluctuation of the air demand. No power runs into the pump when inactive. There is no better way to save energy than that.

When we talk about our multi-pump compressors, many contributing factors need to be taken into the consideration. Fewer vibration, small start-up torque, small body and fewer parts required to maintain the pump's functionality. These characteristics were direct contribution for the multi-pump assembly. As we studied further, we came to recognize its potential not only in the usability but also in the enhancement in our own production and the researches. The level of social awareness about the environment conservation started to rise in 80's. Back then we were not requested by anyone to change our process to become more eco-frindly however, we still included all the eco-factors in our development plan. Those are low vibration, low noise, cleanliness of the air, energy efficiency and low maintenence, just name a few. As a result of the seamless effort like this, our scroll compressor is recognized as an industrial equipment that supports SDGS Global goal.

Statement is based on our own study on the industrial oil free scroll compressor larger than 0.75kW