Development and manufacturing of customized, high-precision miniature and spindle ball bearings for medical technology, aerospace and industry.
Gebr. Reinfurt GmbH & Co. KG (GRW)
Rimpar (DE) · Prachatice (CZ) · Bloomfield, Connecticut (US) · Singapore (SG) · Devon (GB)New on Amplifa
About GRW
GRW (Gebr. Reinfurt GmbH & Co. KG) develops and manufactures customized, high-precision miniature ball bearings and spindle bearings, complemented by ball bearing testing technology such as the Orakel dental test bench as well as accessories such as wave spring washers, compensating washers and plain washers. The solutions are designed for extreme conditions – temperatures from -270 °C to 450 °C, speeds up to 600,000 min-1 in dental handpieces, operation under vacuum, in seawater or under sterilization. Based on a design kit with 5 ring materials, 30 cage materials, more than 180 lubricants and 19 coatings, individual bearing designs are realized, supported by CAE/CAD tools and FEM simulation. Manufacturing and development take place at the headquarters in Rimpar near Würzburg; pre-assembly and final assembly are carried out in cleanrooms (ISO 7 and ISO 8) at the assembly site in Prachatice (Czech Republic). The portfolio is complemented by laboratory services such as lubricant analysis, FTIR spectroscopy, gold plating, browning, passivation and corrosion testing. Customers are OEMs and distributors from medical technology/dental, aerospace, industry/robotics, process technology and the food industry. Founded in 1942, the company employs around 600 people worldwide and belongs to the US-based Kaman Corporation.
- Site
- Rimpar
- Processes
- Manufacturing of customized, high-precision ball bearings (miniature and spindle bearings), Pre- and final assembly of high-precision ball bearings in the cleanroom, Testing technology: dental test bench for speed measurement of high-speed instruments (service life, Thomas gold plating (functional and decorative gold plating of components), Ultrasonic cleaning, Hot and cold browning, Passivation of high-alloy steels, Coatings (19 different coatings in the portfolio)
- Materials
- Deep groove ball bearing steel (steel sheet for steel crown cages), Polyamide-imide (PAI) with solid lubricant (XTRAlon cage material), High-alloy steels (passivatable, corrosion-resistant), Rolling bearing steels, Polyamide-imide (XTRAlon), More than 180 lubricants, 19 coatings
- Certificates
- ISO 7 cleanroom (Prachatice), ISO 8 cleanroom (Prachatice), In-house laboratory (Rimpar)
- Founded
- 1942
- Employees
- 600
- Industries
- Medical technology/Dental, Aerospace, Industry/Robotics, Process technology, Food industry, Model making
- 01
Engineering and design (CAE/CAD, FEM)
- 02
Ball bearing manufacturing in Rimpar
- 03
Surface treatment (gold plating, browning, passivation, coatings)
- 04
Testing (test benches, laboratory services)
- 05
Pre- and final assembly in the cleanroom (Prachatice)
- 06
Sales worldwide
Materials and Processes
Rolling bearing steels
Base ring materials for ball bearings; corrosion-resistant high-alloy steels also capable of being passivated.
Polyamide-imide (XTRAlon)
Patented cage material with chemically coupled solid lubricant for high-temperature and dry-running applications.
More than 180 lubricants
Individual selection to adapt friction, service life and running noise.
19 coatings
Portfolio for adapting bearing properties to extreme operating conditions.
Sites
Rimpar
DEHeadquarters, manufacturing and development
- Orakel dental test bench (load 0.1–6 N, 20,000–600,000 min-1)
- Test benches for service life, friction torque and noise measurements
- In-house laboratory (FTIR, corrosion testing)
Prachatice
CZAssembly site with cleanroom
- ISO 7 cleanroom, approx. 1,400 m²
- ISO 8 cleanroom, approx. 450 m²
Bloomfield, Connecticut
USGRW USA sales office: sales, engineering, distribution
Singapore
SGAPAC sales office
Devon
GBUK/Ireland sales office
Industries
Processes & technical limits
| Processes | Tolerance | Max. part | Weight | Lot size | Materials |
|---|---|---|---|---|---|
| Manufacturing of customized, high-precision ball bearings (miniature and spindle bearings)Assembly | – | – | – | 10 pieces – 1,000,000 pieces | – |
| Pre- and final assembly of high-precision ball bearings in the cleanroomAssembly | – | – | – | – | – |
| Testing technology: dental test bench for speed measurement of high-speed instruments (service lifeTesting | – | – | – | – | – |
| Thomas gold plating (functional and decorative gold plating of components)Surface | – | – | – | – | high-alloy steels |
| Ultrasonic cleaningSurface | – | – | – | – | – |
| Hot and cold browningSurface | – | – | – | – | – |
| Passivation of high-alloy steelsSurface | – | – | – | – | high-alloy steels |
| Coatings (19 different coatings in the portfolio)Surface | – | – | – | – | – |
| Heat treatment (steam pressure sterilization, thermal disinfection)Surface | – | – | – | – | – |
| Laboratory services: general analytics (pH value, acid concentration, oil/preservative content,Testing | – | – | – | – | – |
| Corrosion testing: salt spray test DIN EN ISO 9227, condensation water test DIN EN ISO 6270Testing | – | – | – | – | steels |
| Further analyses in the laboratory network: SEM, EDX, XRF, DSC, thermogravimetry (TGA),Testing | – | – | – | – | steels |
| Chemical deburring with natural-fiber-reinforced polymersSurface | – | – | – | – | natural-fiber-reinforced polymers |
| Product development/design of ball bearing solutions (CAE, CAD, FE calculations, design kit:Engineering | – | – | – | – | rolling bearing steels, polyamide-imide (PAI) |
3 Anlagen & Maschinen
| Machine | Manufacturer / model | Quantity | Working area | Year built | Site |
|---|---|---|---|---|---|
| Dental test bench (Orakel test bench) | GRW Dental Test Bench | – | Load 0.1–6 N (±0.1 N), speeds 20,000–600,000 min-1 | – | Rimpar |
| Test benches for service life, friction torque and noise measurements (partly self-developed) | GRW | – | – | – | Rimpar |
| Cleanroom manufacturing/assembly facility Class ISO 7 (1,400 m²) and Class 8 (450 m²) | – | – | – | 2012 (ISO | Prachatice, Czech Republic |
Additional services
Reference customers
Quality and Testing Technology
GRW ensures quality through partly self-developed test benches for service life tests, friction torque measurements, stiffness tests, environmental simulation tests, noise measurements and vibration analyses, as well as through an in-house laboratory with FTIR spectroscopy and corrosion tests (salt spray test DIN EN ISO 9227, condensation water test DIN EN ISO 6270). Pre-assembly and final assembly are carried out in spatially separated cleanrooms of classes ISO 7 and ISO 8.
| Evidence | Rimpar | Prachatice |
|---|---|---|
| ISO 7 cleanroom (Prachatice) | ||
| ISO 8 cleanroom (Prachatice) | ||
| In-house laboratory (Rimpar) |
History
- 1942
Founding of the Reinfurt brothers in Würzburg
- 1958
The Rimpar plant becomes the company's site
- 1996
Founding of the assembly site in Prachatice, Czech Republic
- 2012
New manufacturing facility for cleanroom assembly in Prachatice (ISO 7)
- 2015
Michael Wilhelm becomes Managing Director (February)
- 2018
Expansion of assembly areas in Prachatice by approx. 1,400 m² including Class 8 cleanroom