Centerless grinding machine

Centreless grinding machines for industrial production

How a centreless grinding machine works

The centreless grinding machine, also known as a centreless grinding machine, is a specialised machine tool for the external cylindrical machining of rotationally symmetrical workpieces without a centre support. In contrast to conventional cylindrical grinding, the workpiece is not clamped between centres, but lies freely between two grinding wheels - a rotating grinding wheel and an opposing regulating wheel - and is supported by a support, usually a so-called guide pad.

The functional principle of the centreless sanding machine is based on the interaction of these three elements. The grinding wheel removes material from the workpiece, while the regulating wheel slowly turns the workpiece and presses it against the grinding wheel. This constellation creates a continuous sanding process that is particularly efficient and precise. The angle and speed of the regulating disc can be adjusted to guide the workpiece through the sanding zone in a targeted manner.

Centreless grinding machines are often used for the manufacturer of high-precision cylinder shapes, such as valve tappets, shafts, bolts or bearing rollers. The advantage lies in the high productivity and the ability to machine very small to very large workpieces with consistently high quality. The machines are particularly insensitive to workpiece deformation caused by clamping and therefore enable reproducible production even with difficult geometries.

Structure of a centreless sanding machine

A centreless grinding machine essentially consists of the machine bed, the grinding wheel spindle with drive, the regulating wheel for controlling the feed of the workpiece and the workpiece support (guide rail). There are also traversing units for adjusting the grinding and regulating wheel positions, a coolant circuit, a dressing system for shaping the grinding wheels and a Control for automated processes. An automation unit for workpiece feed and removal is optionally integrated.

Other types of cylindrical grinding machines

At maschinenauswahl.de, we differentiate between the following types of cylindrical grinding machines:

The following keywords are often used in the search for centreless grinding machines: Cylindrical grinding machines centreless, grinding machine metal industry, industrial grinding machine metal, metal processing machines, machine finder

Production with the centreless grinding machine

There are two main variants of the process: plunge-cut grinding, in which the grinding wheel moves into the stationary workpiece, and through-feed grinding, in which the workpiece runs continuously through the machine.

Plunge-cut grinding

Centreless plunge-cut grinding is a high-precision grinding process for the targeted machining of defined workpiece areas, in particular shoulders, recesses or short cylindrical surfaces. The rotating grinding tool is inserted radially into the rotating workpiece until the desired depth is reached. The workpiece remains stationary in the axial direction during the process. This method enables the grinding of narrow contours with high dimensional accuracy and fine surface quality. Plunge-cut grinding is often used in series production for crankshafts, gear wheels or bearing journals.

Through-feed grinding

Throughfeed grinding is a continuous grinding process in which the workpiece is guided between a grinding wheel and a regulating wheel and runs axially through the grinding zone. The regulating wheel turns the workpiece and simultaneously moves it in a longitudinal direction while the grinding wheel removes material from the surface. This process is ideal for cylindrical workpieces with a constant geometry, such as bolts, axles or shafts. Throughfeed grinding is characterised by high productivity, short cycle times and consistent quality.

Application in industrial metalworking

Centreless grinding machines are used in numerous branches of industry in which large series of rotationally symmetrical components are manufactured. Their use is particularly widespread in the automotive industry, in machine and tool construction, in bearing technology, medical technology and in the aerospace industry.

Typical workpieces are

Valve tappets
piston pins
Camshaft journals
Needles for needle bearings
Pins and bolts
Crankshaft journals
Precision shafts
Roller bearing inner rings
Ball screws
Medical metal pins

Thanks to their high precision and efficiency, centreless grinding machines are ideal for series and mass production.

Accuracy in centreless grinding

Extremely high accuracies can be achieved with centreless grinding, which are particularly appreciated in series production. Dimensional tolerances in the range of ±1 to ±2 micrometres can be easily achieved with modern machines and optimum process parameters. The roundness of the workpieces can also be reduced to less than 1 µm. Factors such as the quality of the grinding wheels, the stability of the machine, the exact alignment of the regulating wheel and a precise workpiece support are decisive for precision. Centreless grinding is therefore ideal for applications with the highest demands on dimensional accuracy and surface quality, such as valve tappets, shafts or precision bearings.

Tools for a centreless grinding machine

The following tools are used in centreless grinding machines:

CBN grinding discs
Aluminium oxide grinding wheels
Diamond grinding wheels
vitrified bonded grinding discs
Resin-bonded grinding wheels
dressing wheels
dressing diamonds
Rubber or synthetic resin regulating discs
Profiled grinding wheels
Grinding discs for plunge-cut grinding

Depending on the application, these tools are designed for high stock removal rates or maximum surface quality.

Accessories and operating materials for a centreless grinding machine

Essential accessories such as workpiece supports, automatic loading systems, dressing devices for grinding and regulating wheels and coolant systems for temperature control are required to operate a centreless grinding machine. Grinding and dressing tools, clamping devices and workpiece guidance systems are also required. To ensure reliable production processes, modern machines are equipped with measuring systems for in-process monitoring and digital machine control. The quality of the abrasive and coolant used has a direct influence on the machining results.

Leading manufacturers of centreless grinding machines

In our manufacturers directory you will find companies that produce centreless grinding machines for metalworking.

The following terms are frequently searched for: Herminghausen centreless grinding machine, Junker centreless grinding machine, Junker Group, Tschudin centreless grinding machine, Tschudin Novartis, Tschudin Swiss, Bahmüller Centreless Grinding Machine, dama Centreless Grinding Machine, Danobat Centreless Grinding Machine, DVS Centreless Grinding Machine, EMAG Centreless Grinding Machine, Geibel Centreless Grinding Machine, GP Centreless Grinding Machines, Jainnher Centreless Grinding Machine, Kaast Centreless Grinding Machine, Kellenberger Centreless Grinding Machine, Kellenberger Centreless Grinding Machine, Knuth Centreless Grinding Machine, Lizzini Centreless Grinding Machine, Okamoto Centreless Grinding Machine, Okuma Centreless Grinding Machine, Palmary Centreless Grinding Machine, Rettificatrici Ghiringhelli Centreless Grinding Machine, Rollomatic Centreless Grinding Machine, Saeilo Centreless Grinding Machine, Schaudt Centreless Grinding Machine, Centreless Grinding Machine Schaudt, Centreless Grinding Machine Studer, Studer Centreless Grinding Machine, Tacchella Centreless Grinding Machine, Toyoda Centreless Grinding Machine, Ulmer Werkzeug-Schleiftechnik Centreless Grinding Machine, United Grinding Group Centreless Grinding Machine, Wagner Centreless Grinding Machine, Weiss Centreless Grinding Machine, WEMA Centreless Grinding Machine, Ziersch Centreless Grinding Machine

Selecting the right centreless sanding machine

If you want to buy a centreless sanding machine, there are several important features and specifications to consider.

These include the maximum workpiece length and diameter, the grinding wheel size, the engine power of the grinding and regulating wheel and the adjustment options for the regulating wheel axis.
The type of grinding process (through-feed or plunge-cut grinding) and the possibility of automation are also important. High-quality machines offer precise setting axes, a thermally stable machine bed and integrated measuring systems.
Equally important are the control technology (CNC), the reproducibility of the machining process and the ease of conversion to new workpiece types.
The manufacturer's service, spare parts supply and training programmes should also be taken into account when purchasing a machine.

Find the centreless grinding machine that suits your production requirements now at maschinenauswahl.de.

All machines from the category Centerless grinding machine