tel. +886-2-278-45675 (1-30)  fax.+886-2-278-45676  e-mail:


spring washer

A spring washer, also known as a grover, is a split washer designed to function as a locking element, preventing the self-unscrewing of threaded connections. This component is utilized in connections where ensuring a secure fixation of connected structural elements is crucial, particularly under conditions of significant vibration.

The grover is a metal part structurally shaped like a ring, cut at an angle. Its ends feature sharp edges slightly spread out to the sides. During installation, the grover is positioned between the mounting surface and the nut. As the nut is tightened, the sharp edges cut into its surface, ensuring a reliable fastening.

Spring washers are manufactured in accordance with the DIN 127 standard using spring-hardened or stainless steel grades. Additionally, materials such as bronze, aluminum, and Monel metal are employed.

Split spring washers find widespread use in instrument making, mechanical engineering, the automotive industry, and various other sectors.

The production of these bushing washers often employs spring-coiling automatic machines. Such equipment facilitates a complete technological cycle for producing spring washers in compliance with standards like DIN 127, DIN 128A, DIN 128B, DIN 6913, and DIN 7980.

The productivity of this equipment depends on the size of the manufactured grovers and ranges from 400 pcs/min to 1000 pcs/min (refer to the video).


spring-coiling machine for the production of spring washers
External view of the machine for the production of grover washers with a wire unwinder

Features of equipment for the production of grover washers

  • The machine axes can operate either synchronously or independently of each other, depending on the control program.
  • The computer equipment control interface is available in Chinese and English.
  • The spring winding equipment has a right- and left-hand winding blade.
  • Taiwanese computer controller and Japanese servomotors.
  • The machine allows you to produce debugging samples manually.

Technical characteristics of the machine for the production of groover washers RG-35

Wire diameter Ø1.5 ~ Ø3.5
Maximum outer diameter of spring washer Ø50 mm
Number of CNC controlled axes 3 axes (wire feed / cams / spring pitch setting)
Max wire feed speed 100 m/min
Wire Feed Setting Value ± 0.01 ~ ± 9999.99 mm
Cam installation size ± 0.1 °C ~ ± 359.9 °C
Number of feed rollers Two pairs
Wire feeder servo motor power 5.5 kW
Cam servo motor power 5.5 kW
Spring pitch servomotor power 1 kW
Dimensions (L×W×H) 1150 mm × 1535 mm × 2000 mm
Machine weight 1060 kg
Power supply 3-phase 380V/50Hz
Servomotor manufactured by Sanyo (Japan)
Computer made by Hust (Taiwan)

Technical characteristics of wire unwinder RG-35A

Feeder Diameter 1100 mm
Load Capacity 300 kg
Rotation Speed 100 m/min
Motor Power 1.1 kW
Equipment Weight 200 kg
Power Supply 220V/50Hz
Packing Size 1180 mm × 780 mm × 1280 mm

Video of equipment operation

CNC spring winding machine for the production of lock washers

Automatic machine for the production of growers 970 pcs/min


grower production equipment

spring lock washer spring lock washer

Model RG-10
Material 22K & S45C SW-57A
Specification 8 mm, 10 mm, 12 mm is used for screws 6 mm, 8 mm, 10 mm is used for screws
Engine power 3 HP
Dimensions of equipment 142 × 112 × 140 cm, 920 kg
Dimensions RE.unit + water cooling tank 65 × 54 × 115 cm, 150 kg
Dimensions of wire pay-off stand 155 × 142 × 80 cm, 395 kg

  • Material Wire: wire springs made of steel.
  • Flattening is carried out by feed handwheel.
  • Flattering process, winding, cutting and forming of washers is performed at the same time.

Copyright © 2007 - 2024 Rost Group & Technology Co., Ltd 
(coordinator and exclusive representative)