History of Simpson

Peter L. Simpson designs a muller mixer with independent muller wheel suspension and becomes the first President of National Engineering Company in Chicago, Illinois. Now Simpson.

on December 15th, Simpson is reorganized into a corporation. Herbert S. Simpson, Peter's son, becomes President and the 2nd generation of family to lead Simpson.

Herbert S. Simpson applies for a U.S. Patent on an early version of the Simpson intensive mixer on August 14th. The patent (US #1,337,333) is granted on April 20th and becomes one of Simpsons most popular early machines. This patent is the first of thousands of patents granted to Simpson around the world.

Simpson is one of the founding members of the Foundry Equipment Manufacturers Association which eventually became CISA.

Simpson completed the acquisition of Standard Sand & Machine Company of Cleveland, Ohio.

Simpson completed the acquisition of the Carol Sand Conditioner and the business of the Carol Engineering Company of Dayton, Ohio.

The Foundry Equipment Manufacturers Association (now CISA) announced Mr. Herbert Simpson has been elected President.

Simpson licenses the Georg Fischer Steel & Iron Works of Schaffhausen, Switzerland to manufacture the complete range of Simpson sand preparation equipment and related spare parts in the European market. The agreement was later extended until terminated by Simpson in 1969 after 36 years of technical cooperation and the installation of thousands of +GF+ built Simpson machines throughout Europe. 

The American Foundry Society announced Mr. Herbert Simpson has been elected AFS President. 

Bruce L. Simpson, son of Herbert, succeeds his father as President becoming the 3rd generation of family to lead Simpson.

On July 26th, Simpson donates $20,000 ($250,000 in 2008 funds) to Northwestern University in Evanston, Illinois to establish the Peter L. Simpson Memorial Scholarship to provide funds each year for research into foundry sand problems. Results of early research were frequently made public property each year via presentations by the researchers at the annual AFS conventions. 

Simpson donates funds to the American Foundry Society to establish the Peter L. Simpson Gold Medal to be given to an individual who, during the year, has made the most constructive and practical contribution to the progress of the foundry industry. 

Simpson joins other industry leaders to establish and fund the Foundry Educational Foundation to assure a continuing supply of technical manpower for the metal casting industry.

Bruce L. Simpson authors the book "Developments of the Metal Casting Industry" which is published by the American Foundrymen's Society to describe the history of the metal casting industry up to approximately 1910. 

Simpson introduces the first of the "F" series mixers (the 05 model in US patent #2576180) - which used lightweight, spring-loaded muller wheels and higher operating speeds.

The American Foundry Society announced Mr. Bruce L. Simpson has been elected AFS President. 

• Simpson completed the acquisition of the "Maple Lead Mixer" from Cunningham Foundry & Machine Company, Ltd. of St. Catharines, Ontario, Canada. 

• Simpson introduces the "Even-Flo" series of sand reclaimer (US patent #761299).

• Simpson introduces the first of the continuous mixer utilizing the principal of back blending. The #22F Simpson Multi-Mull was awarded US patent #2943801. The Simpson Multi-Mull has evolved into the most popular molding sand mixers in the world. 

On May 4th, Simpson President Mr. Bruce L. Simpson and Mr. Kakichi Nagai of Sintokogio in Nagoya, Japan sign the first Technology License Agreement which provided Sintokogio Ltd. with the right to produce Simpson sand preparation technology in Japan for the Asian market. The cooperation with Sintokogio has resulted in tens of thousands of Simpson installations throughout Asia.

Simpson completes the design work for the new "G" series batch and continuous mixers by introducing the 1 1/2G, 2G, 2 1/2G and 3G Simpson Mixer-Mullers and 215G, 22G, 225G and 23G Simpson multi-Mulls. 

Simpson introduces the "Simpson Multi-Cooler" series of continuous sand cooling and pre-mixing technology.

Simpson established their wholly owned business in Europe - Simpson Maschinen AG in Zug, Switzerland. Today, Simpson Technologies GmbH is based in Euskirchen, Germany and services the European market. 

Henry W. Dienst becomes President & Chief Executive Officer of Simpson and the 4th generation of family to lead Simpson.

Bruce L. Simpson is awarded the William H. McFadden Gold Medal by the AFS "for over four decades of inspiring leadership, effective motivation of management and for the diligent encouragement of young men toward careers in the industry."

The Foundry Equipment Manufacturers Association (now CISA) announced Mr. Henry W. Dienst has been elected FEMA President. 

On November 1st, Simpson relocates from their downtown Chicago location to a new 3,000 square-meter facitlity in suburban Aurora, Illinois.

The Casting Industry Suppliers Association announced Mr. Bruce W. Dienst has been elected CISA President. 

• Simpson acquires the Dietert Automation Products from Georg Fischer Foundry Systems of Holly, Michigan. In the transaction, Simpson acquired all the assets of the Dietert Automation Products. 
  
  
• Mr. Bruce W. Dienst becomes President & COO of Simpson and the 5th generation of the Simpson family to lead the company. Mr. Dienst is the great, great-grandson of Simpson founder, Peter Simpson.

On March 1st, National Engineering Company renames the company to Simpson Technologies Corporation. 

The American Foundry Society announced Mr. Henry W. Dienst has been elected AFS President.

Simpson completed the acquisition of longtime rival Beardsley & Piper LLC of Chicago, Illinois, The centerpiece of the acquisition was the addition of the "Speedmullor high-speed, high-intensity batch muller to Simpson's line of sand preparation equipment. Like Simpson, Beardsley & Piper enjoyed considerable success in metal casting markets throughout the world and was known and respected as an innovator. Not only did Beardsley & Piper invent the original Speedmullor in 1933, but they also invented the first automated matchplate molding machine, the "Matchblowmatic", in 1962 - a development that revolutionized the industry. 

Simpson concluded the acquisition of the sand testing equipment business of the company R. Geroasa SRL based in Rosario, Argentina. Simpson acquired all the intellectual property and rights related to the product line and have formed a long-term strategic partnership with R. Gerosa SRL to assure a strong future for the product line. R. Geroasa SRL will continue to actively participate in the research, development and manufacturing of the product line. 

Simpson completed the acquisition of another longtime rival Hartley Controls Corporation of Neenah, Wisconsin, including their joint venture company in India - Wesman Hartley Pvt. Ltd., from Neenah Foundry Company. The centerpiece of the acquisition was the addition of the "Hartley" range of on-line control and automation technology.

On February 28th, Simpson and Wesman Engineering form a 50-50 joint venture company Wesman Simpson Technologies Pvt. Ltd. in Kolkata, India to produce Simpson equipment for the Inidan market. 

The Foundry Educational Foundation announced that Bruce W. Dienst has been elected FEF President.

2015

The American Foundry Society announced Mr. Bruce W. Dienst has been elected AFS President - the 4th consecutive generation of the Simpson family to serve AFS as President.

On January 31st, Simpson GmbH completed the acquisition of the DISA (formerly Georg Fischer, +GF+) sand laboratory testing equipment product line from DISA Industrie AG in Schaffhausen, Switzerland. The addition of the former Georg Fischer sand laboratory equipment product line together with Simpson own sand testing equipment product line purchased from R. Gerosa SRL establishes Simpson as the largest supplier of foundry sand laboratory and control technology in the world. 

Simpson turns 110 years old.

Simpson joins Norican Group.

The first SIMPSON MULTI-COOLER® has been built in India by Norican—marking a new chapter in our ongoing growth and collaboration. Trusted by foundries worldwide, the Simpson Multi-Cooler continues to be manufactured in the US, Europe, and now India—each delivering the same exceptional quality and performance that define Simpson.

In September 2025, Simpson welcomed John Jennings as Senior Vice President. Based in Naperville, John is focused on advancing global operations, strengthening manufacturing and engineering excellence, and driving innovative solutions to support Simpson’s growth across international markets. Full article.