Mitsui Seiki
Mitsui Seiki Kogyo Co., Ltd. (三井精機工業株式会社) is a 1928-founded Japanese manufacturer of sub-micron precision machine tools and proprietary Z-screw industrial compressors, serving enterprise customers in precision molds, optics, aerospace, and large-scale plants across Japan via direct sales and a 121-point service network.
- Company typePrivate
- Founded1928
- HeadquartersSaitama, Japan
- Headcount501–1,000
- GTM typeB2B
- OfferingHardware or Manufacturing
What Mitsui Seiki does
Mitsui Seiki Kogyo Co., Ltd. (三井精機工業株式会社) is a privately held Japanese manufacturer founded in 1928 and headquartered in Kawaguchi, Saitama Prefecture, operating with 501-1000 employees. The company operates two core product lines built around complementary precision-engineering competencies. The first is high-precision machine tools, including 5-axis vertical machining centers (the Vertex series, which received the 36th Machine Industry Design Award / Japan Brand Award), horizontal machining centers, jig borers, jig grinders, and thread grinding machines — with the latter holding a near-100% domestic market share in Japan's precision ball screw grinding segment. The second is industrial air compressors, differentiated by the proprietary Z-screw compression mechanism, deployed across water-lubricated oil-free series (i-14000 X, U-14000, ZU-Quatro, ZU), oil-lubricated series (Zgaiard X3/X4), scroll compressors (Escal, D-escal), and outdoor-rated units (Zgaiard SKY). Sub-micron machining accuracy is achieved through hand-scraping (kissage) assembly techniques performed in temperature-controlled facilities.
The company's revenue model is anchored on direct enterprise sales of capital equipment with quote-based, multi-year-contract pricing, supplemented by recurring service revenue from an extensive after-sales infrastructure. Mitsui Seiki operates 121 authorized service factories covering all 47 Japanese prefectures, supporting installation, maintenance, repair, and add-on systems such as the Z-Cloud remote monitoring platform, Red-CX multi-compressor controller (up to 8 units), and Z-Mate II PC monitoring (up to 50 compressors). The go-to-market motion is enterprise field sales with website-driven inquiries and trade-show lead generation at events such as Japan PACK, Mechatronics Japan (MECT), and the company's own MTF technical fairs. Customer segments are diversified across precision mold manufacturers, optical component producers, aerospace/aircraft parts manufacturers, and large-scale industrial plants requiring clean compressed air. Geographic reach is almost entirely domestic Japan, with no disclosed international operations, M&A, or funding activity in the available data.
Mitsui Seiki firmographics
Firmographics- Name
- Mitsui Seiki
- Legal name
- 三井精機工業株式会社
- Website
- https://mitsuiseiki.co.jp
- Company type
- Private
- Founded year
- 1928
- Operating status
- Operating
- Headcount range
- 501–1,000 employees
- Short description
- Mitsui Seiki Kogyo Co., Ltd. (三井精機工業株式会社) is a 1928-founded Japanese manufacturer of sub-micron precision machine tools and proprietary Z-screw industrial compressors, serving enterprise customers in precision molds, optics, aerospace, and large-scale plants across Japan via direct sales and a 121-point service network.
- Ownership category
- akta.pro rank
Mitsui Seiki industry classification
Industry- Product category
- Precision Machine Tools and Industrial Air Compressors
- NAICS
- Other General Purpose Machinery Manufacturing (3339), Pump and Compressor Manufacturing (33391)
- SIC
- Machine Tools, Metal Cutting Types (3541), General Industrial Machinery & Equipment (3560)
- akta.pro primary industry
- Motion & Machine Control (CNC, Robotics Controllers, Servo/Motion Controllers) (IMAGABAG)
- akta.pro secondary industry
- Pump & Compressor Packages (Skids, Booster Sets) (IMAHANAG)
Keywords
Where Mitsui Seiki is headquartered
LocationHeadquarters
- HQ city
- Saitama
- HQ country
- Japan
- HQ region
- Asia
Offices1 record
Markets served
Mitsui Seiki business model
Business model- GTM type
- B2B
- Offering type
- Hardware or Manufacturing
- Cost components
- Personnel, Supply Chain, Operations, Technology or R&D, Infrastructure, Marketing or Sales
Revenue model
- Precision Machining Equipment Sales: Sale of high-precision CNC machining centers including 5-axis vertical machining centers (Vertex series), jig grinding machines, and thread grinding machines. One-time capital equipment sales with potential for spare parts and upgrades.
- Industrial Compressor Sales and Service: Sale of water-lubricated oil-free screw compressors (Z-Cloud and Z-Mate series) along with associated maintenance, repair, and after-market services through their nationwide service network.
- Technical Services and Maintenance: Comprehensive after-sales technical support, maintenance, and repair services provided through 121 authorized service factories across all 47 Japanese prefectures.
Pricing tiers
| Model | Billing | Price |
|---|---|---|
| Other | Multi-year contract | Custom enterprise quotation |
Go-to-market motion1 record
Distribution channels2 records
Marketing channels3 records
Mitsui Seiki product offering
Product offeringCore offering
Mitsui Seiki manufactures two core product lines: high-precision machine tools (5-axis vertical machining centers, horizontal machining centers, jig borers, jig grinders, and thread grinding machines) and industrial air compressors built around its proprietary Z-screw water-lubricated oil-free compression mechanism. The company sells these as customized capital equipment to industrial manufacturers in Japan, supported by 121 authorized service factories covering all 47 Japanese prefectures for installation, maintenance, and after-sales support.
Product overview
Mitsui Seiki (三井精機工業株式会社) manufactures two core product lines: high-precision machine tools and industrial air compressors. The machine tool portfolio includes 5-axis vertical machining centers (Vertex series), horizontal machining centers (4-axis and 5-axis configurations), jig borers, jig grinders, and thread grinding machines (with near-100% domestic market share for precision ball screw grinding). The compressor portfolio centers on the proprietary Z-screw compression technology across water-lubricated oil-free series (i-14000 X, U-14000, ZU-Quatro, ZU) and oil-lubricated series (Zgaiard X/Zgaiard), complemented by scroll compressors (Escal, D-escal) and outdoor-rated models (Zgaiard SKY). Supporting offerings include Z-Cloud cloud monitoring, Red-CX multi-compressor control, Z-Mate II PC monitoring, clean air filtration systems, and receiver tanks. The company operates 121 designated service factories across Japan's 47 prefectures.
Differentiator
Problem solved
Functional benefit
Products and services
- Machine Tools (工作機械) High-precision CNC machining centers including 5-axis and vertical/horizontal configurations, jig borers, jig grinders, and thread grinding machines manufactured in temperature-controlled facilities using hand-scraping techniques to achieve sub-micron precision. The line serves precision mold manufacturers, optical component producers, and aerospace parts manufacturers in Japan.
- Industrial Compressors (コンプレッサ) Industrial air compressors including water-lubricated oil-free screw compressors, oil-lubricated screw compressors, and scroll compressors. Built around the proprietary Z-screw compression mechanism, the lineup serves large-scale factories and industrial plants needing clean, oil-free compressed air.
- Vertex Series (5-axis vertical machining center) 5-axis vertical machining center with cube-on structure achieving jig borer-level precision. Compact footprint (2m x 3m) with up to 500mm diameter workpiece capacity, built-in tilt/rotary table, thermal displacement compensation, and 0.1 micron minimum feed. Targets mold, optical, and aerospace precision component manufacturers.
- Horizontal Machining Centers (横形マシニングセンタ) Horizontal machining centers in 4-axis and 5-axis configurations including trunnion type, table-on-table type, and spindle-tilt type. Pallet sizes range from compact 500mm to large 2500mm workpiece capacity machines for heavy industrial precision manufacturing.
- Vertical Machining Centers (立形マシニングセンタ) Vertical machining centers including 3-axis and 5-axis configurations, precision centers with linear motors, and profile centers for high-precision machining applications.
- Jig Borers (ジグボーラー) Ultra-precision jig borers considered the ultimate mother machine for machining centers, achieving micron-level accuracy through rigorous craftsmanship. Available in traditional and large types up to 3m stroke for high-precision reference and master component manufacturing.
- Thread Grinding Machines (ねじ研削盤) Thread grinding machines for precision ball screw grinding with near-100% domestic market share in Japan. Includes male thread, female thread, and heavy-duty grinding types with various grinding lengths for ball screw production.
- i-14000 X Series (Water-lubricated oil-free inverter compressor) Water-lubricated oil-free inverter screw compressor with Z-screw technology achieving up to 7% increase in discharge air volume. Features SUS rotor for high durability and wear resistance. Power range 15-220kW for industrial plants and large factories.
- U-14000 Series (Water-lubricated oil-free standard compressor) Standard water-lubricated oil-free screw compressor with IE3 premium efficiency motor compliant with Top Runner regulations. Power range 15-75kW for industrial compressed air applications requiring clean, oil-free air.
- ZU-Quatro Series (Compact water-lubricated oil-free compressor) Compact water-lubricated oil-free screw compressor delivering one rank up air volume in its horsepower class. Power range 7.5-11kW for smaller industrial applications needing oil-free compressed air.
- ZU Series (Large-scale water-lubricated oil-free compressor) Large-scale water-lubricated oil-free screw compressor for plants and large factories with top-class discharge volume in same horsepower class. Power range 100-120kW.
- Zgaiard X3 Series (Oil-lubricated screw compressor) Oil-lubricated screw compressor with Z-screw technology available in inverter and constant-speed variants. Features Top Runner regulation compliance, 50°C ambient operation capability, and up to 10% increased discharge air volume. Power range 22-150kW.
- Zgaiard X4 Series (Oil-lubricated screw compressor) Oil-lubricated screw compressor series featuring Modbus communication, browser-based monitoring, Wi-Fi connectivity, and multi-drop control for up to 6 compressors. Designed for ambient temperature 50°C operation with emergency stop button standard on all models.
- Escal Series (Scroll compressor) Environment and energy-saving focused scroll compressor with smooth rotation for efficient power, automatic start-stop system with energy-saving unloader. Power range 3.7-5.5kW for smaller industrial and workshop applications.
- D-escal Series (Oil-free scroll compressor) Oil-free scroll compressor using no oil at all, delivering clean air. Features automatic start-stop system for intermittent operation energy savings. Power range 3.7-7.4kW for applications requiring clean compressed air.
- Zgaiard SKY Series (Outdoor compressor) Outdoor-rated screw compressor with IP23 waterproof protection, compact and powerful design for outdoor installation. Features rain-resistant louvers and waterproof connectors for outdoor deployment in industrial facilities.
Quantifiable outcome
- Dominant near-100% market share in Japan's precision ball screw grinding machine market
- +1 more outcomes
Companies that use Mitsui Seiki
Customer profileNamed customers4 records
Segments4 records
Ideal customer profiles4 records
Mitsui Seiki technology and API
TechnologyTechnology focussed No
API detail
- Has API
- No
- API docs
- API detail
Core technology
AI maturity
App detail
Feature4 records
Mitsui Seiki partnerships and signals
Strategic signalScale indicators3 records
Recent moves5 records
Expansion highlights5 records
Mitsui Seiki competitors and assessment
Company assessmentDirect peers
- Yamazaki Mazak: Japan's largest machine tool maker and Mitsui Seiki's closest direct competitor in 5-axis vertical machining centers and complex CNC machining. Both serve precision mold, aerospace, and optical manufacturers with high-end multi-axis solutions, though Mazak operates at significantly larger scale globally.
- DMG MORI: Global leader in 5-axis CNC machining centers and turnkey machining solutions, formed through merger of Japan's Mori Seiki and Germany's Gildemeister. Directly competitive with Mitsui Seiki's Vertex and horizontal machining center product lines for precision mold and aerospace customers.
- Makino Milling Machine: Japanese precision machine tool maker specializing in vertical machining centers, horizontal machining centers, and EDM. Competes head-to-head with Mitsui Seiki in aerospace, mold, and high-precision die/mold applications requiring micron-level accuracy.
- Okuma Corporation: Japanese CNC machine tool manufacturer producing machining centers, lathes, and multi-axis machines with proprietary OSP control. Direct competitor to Mitsui Seiki in the domestic precision machining center market for factory automation customers.
- Shibaura Machine (formerly Toshiba Machine): Japanese manufacturer of machine tools (machining centers, lathes), injection molding machines, and industrial equipment. Overlaps with Mitsui Seiki on CNC machining centers and shares Japanese precision manufacturing customer base including semiconductor and automotive.
- Nakamura-Tome Precision Industry: Japanese precision turning and machining center maker (multi-axis lathes, multitasking machines). Direct competitor in mid-sized precision machine tool segment serving aerospace and mold industries, with comparable mid-market scale.
- Yasda Precision Tools: Japanese specialist in precision jig grinding and ultra-precision machining centers, similar heritage to Mitsui Seiki in sub-micron craftsmanship. Most directly comparable in terms of niche precision positioning, jig grinding product overlap, and Japanese-domestic market focus.
- Kobelco (Kobe Steel) Industrial Compressor Division: Kobe Steel's industrial machinery division produces screw compressors and oil-free compressors for the Japanese market. Direct domestic competitor to Mitsui Seiki's Z-screw compressor portfolio, serving similar Japanese factory and industrial compressed-air customers.
Broad incumbents
- Atlas Copco: Global market leader in industrial compressors and a major machine tool/vacuum solutions provider. Broad incumbent competitor to Mitsui Seiki's compressor business (especially GA/GR oil-injected screw and oil-free ranges) with deeper digital platform (SmartLink) and global service network.
- Ingersoll Rand: Global diversified industrial manufacturer of compression equipment, fluid handling, and process solutions. Overlaps with Mitsui Seiki on industrial oil-free and oil-lubricated screw compressors, with much broader global scale and IoT-enabled service offerings.
Market position
Strengths5 records
Weaknesses5 records
Competitive moat5 records
Key risks5 records
Key highlights6 records
Customer concentration
Mitsui Seiki social profiles
Digital presenceMitsui Seiki financial estimates
Financial estimateRevenue estimate
Valuation estimate
Mitsui Seiki leadership team
Management profileNumber of profiles
Profiles3 records
Mitsui Seiki funding detail
Funding detailFunding overview
Funding rounds
Investors
Funding detail is available on the Subscription and Enterprise plan.Contact sales →
Mitsui Seiki M&A and investment
M&A and investmentM&A
Investments
M&A and investment is available on the Subscription and Enterprise plan.Contact sales →
Frequently asked questions about Mitsui Seiki
What does Mitsui Seiki do?
Mitsui Seiki manufactures two core product lines: high-precision machine tools (5-axis vertical machining centers, horizontal machining centers, jig borers, jig grinders, and thread grinding machines) and industrial air compressors built around its proprietary Z-screw water-lubricated oil-free compression mechanism. The company sells these as customized capital equipment to industrial manufacturers in Japan, supported by 121 authorized service factories covering all 47 Japanese prefectures for installation, maintenance, and after-sales support.
Is Mitsui Seiki a public or private company?
Mitsui Seiki is a private company. It is classified as unknown and is currently operating.
When was Mitsui Seiki founded?
Mitsui Seiki was founded in 1928. It employs 501 to 1,000 people.
Where is Mitsui Seiki based?
Mitsui Seiki is headquartered in Saitama, Japan, in the Asia region.
How does Mitsui Seiki make money?
Three revenue lines are on record. Precision Machining Equipment Sales are the primary driver. The others are industrial Compressor Sales and Service and technical Services and Maintenance.
Who are Mitsui Seiki's main competitors?
Direct peers on record are Yamazaki Mazak, DMG MORI, Makino Milling Machine, Okuma Corporation, Shibaura Machine (formerly Toshiba Machine), Nakamura-Tome Precision Industry, Yasda Precision Tools and Kobelco (Kobe Steel) Industrial Compressor Division. Broad incumbents are Atlas Copco and Ingersoll Rand.
Does Mitsui Seiki have an API?
No public API is recorded for Mitsui Seiki.
What industry is Mitsui Seiki in?
Mitsui Seiki's product category is Precision Machine Tools and Industrial Air Compressors. Its primary akta.pro industry code is IMAGABAG, Motion & Machine Control (CNC, Robotics Controllers, Servo/Motion Controllers), with a secondary code of IMAHANAG, Pump & Compressor Packages (Skids, Booster Sets). Its NAICS code is 3339 and its SIC code is 3541.