James Webb Telescope parts

Mitsui Seiki Machines

High-precision Machines

Mitsui Seiki manufactures a diverse range of high-precision machines designed to meet the most demanding industrial applications. Our product lineup includes advanced vertical and horizontal machining centers, jig borers, jig grinders, and thread grinders, all known for their exceptional accuracy and durability.

Horizontal Machining

Cast iron varies in chemical compositions and granular structures, but our structures have a “spring memory” for consistent flexing and returning to the original position, ensuring process predictability, while Mitsui Seiki’s higher cast iron grades are treated with gas emulsion processes to control material composition. View Horizontal Machining Machines

Vertical Machining

Many of the machining systems we build are custom-engineered for our clients, yet they share key attributes like our manufacturing and assembly process, construction components, hand-scraped way mounting surfaces, advanced spindle technology, sophisticated control systems, safety considerations, and optimal maintenance features. View Vertical Machining Machines

Jig Grinders

Hand scraping, a century-old technique, allows us at Mitsui Seiki to hand-fit components to precise geometric tolerances, achieving less than 2 arc seconds of straightness in all axes of large machines—impossible with only machined or ground surfaces. View Jig Grinders Machines

Jig Borers

Mitsui Seiki’s Kawajima factory in Japan, built in 2001, is the world’s premier facility for precision machine tool production, meticulously designed for the utmost precision in manufacturing our entire product line, starting with our “mother” jig boring machines. View Jig Borers Machines

Mitsui Seiki machines are trusted by

ITP Aero MTU Aero Engines Rolls Royce General Electric EATON Sikorsky Draper GKN Pratt & Whitney Collins Aerospace