Cylindrical grinding machine. Purpose and device of cylindrical grinding machines

There are many different metal processing equipment that can be used for surface grinding. Grinding is a mechanical treatment that allows you to change the surface roughness and shape features of the part. Some models can be called universal, their purpose is grinding parts of various shapes. The most widespread are cylindrical grinding machines, the purpose of which is to grind cylindrical workpieces.

Appointment

Cylindrical grinding machines are used for processing the outer cylindrical surface, the workpiece is fastened in the centers and the chuck. In this case, longitudinal and transverse feed can be carried out to achieve the desired result. The universal version is suitable for various sizes, some types can be used in industry for the production of especially large parts.

During the operation of the universal machine with centers, the direction of rotation of the workpiece is opposite to the direction of rotation of the abrasive material. Such models can be used in various types of production.

It should be noted that the cylindrical grinding machine is used at the final stage of production. Centerless and other types of models carry out grinding after turning, milling, drilling and so on.

main parameters

When choosing equipment, one should take into account its type, which determines many important parameters of grinding. The main parameters include:

1. Possible sizes of the center to be installed. In the case of a centerless model, an important indicator is the size of the table.
2. The diameter of the circle and the speed of its rotation. Universal versions can be used to obtain parts of various shapes, they can be tapered.

All important information is indicated in the passport. The drawing and the passport allow you to determine what technical characteristics the design has. Drawings are drawn up taking into account GOST, as well as a passport.

The above information should be taken into account when choosing a model, the diagram of a cylindrical grinding machine reflects all its features. Therefore, to determine important points, drawings and a passport drawn up in accordance with GOST should be considered.

Classification

Certain points indicated in the drawing and passport determine the following classification of grinding equipment:

1. Universal ones have a rotary working table, it is possible to rotate the workpiece and the grinding wheel itself. The universal version is supplied with an additional headstock.
2. Simple ones allow you to process only certain workpieces.

Numerical control allows increasing the degree of work automation several times. At the same time, we highlight the following points:

1. High grinding precision. The mechanism that is used for fastening and feeding the circle, with automatic feeding, allows you to obtain dimensions that can have a deviation of only a few hundredths of a millimeter.
2. Productivity is greatly improved. Most of the stages of the technological process are performed automatically, which means that they do not require operator intervention.
3. Decreases the likelihood of marriage. By reducing how many steps a person will perform, you can reduce the likelihood of problems.
4. Costs are reduced due to the fact that one operator can serve several workplaces.

The CNC cylindrical grinding machine is quite rare, since it is rarely used in large-scale and mass production. The cost due to the inclusion in the design of the numerical control system increases significantly, so it should be used only in large-scale production.

Cylindrical grinding machines for metal with CNC from the Swiss company STUDER in the warehouse of GALIKA AG in Moscow - in stock and on order. STUDER stands for hardware and software, system integration and service of the highest Swiss quality. The company has 100 years of experience in the design and manufacture of grinding equipment.

The hand-operated machines STUDER S20 and STUDER S30 are designed for grinding parts in one-off and small-batch production. They are suitable for use in any industry that produces precision small parts. Operation is very simple and changeover is possible within a short time.

Universal cylindrical grinding machines

Universal cylindrical grinding machines with CNC are designed for grinding small, medium, large parts in piece and batch production.

Industrial cylindrical grinding machines

The STUDER S11 model is designed for those customers who are looking for serial production of small shafts and bushings, external machining with high speed and high precision.
STUDER S22 is a production platform. Its main purpose is the mass production of medium-sized customer parts. The combined machining STUDER S242 ideally combines cylindrical grinding and turning technologies.

SCHAUDT cylindrical grinding machines

SCHAUDT is a German manufacturer of high quality grinding machines. The company sets global standards in technology, precision and quality for center grinding of round and non-round parts. The SCHAUDT FlexGrind M is designed for grinding long and heavy workpieces.

Cylindrical grinding machines belong to the class of metalworking equipment. With their help, precise grinding of metal workpieces is performed on the outer surface. Structurally, machines of this type differ significantly from similar equipment.

Equipment design features

The principle of operation of cylindrical grinding machines is based on clamping the workpiece using a guide wheel or mounting in cents. In this case, processing is performed by touching the working rotating abrasive with the surface of the part. In this way, material is removed evenly with the formation of an optimal roughness index.

The classic layout of the machine is a combination of turning and grinding. A special block is provided for fixing the workpiece in the structure. This can be a chuck system that holds the part in a horizontal position. An alternative option is to use an additional wheel that presses the workpiece against the abrasive.

The cylindrical grinding machine has the following advantages of use:

• the ability to process parts with different dimensions. It is important to take into account their mass;
• fine tuning of parameters. To ensure a high quality of grinding, it is recommended to purchase models with an automatic feed;
• selection of a machine model for specific production tasks. This will maximize productivity and reduce product costs.

However, in order to choose the optimal model of the machine, it is necessary to familiarize yourself in detail with their varieties and performance. It all depends on the configuration of the workpieces, as well as the requirements for the quality of grinding.

An important point is the configuration of the abrasive disc - its grain size, working surface area. These characteristics directly affect the grinding quality of the steel workpiece.

Types of cylindrical grinding machines

In practice, circular or oval workpieces are machined on cylindrical grinding machines. Grinding complex parts on this equipment is impossible due to the specifics of its design. This must be taken into account when choosing a machine model.

The most common models of cylindrical grinding machines are equipment in which parts are installed in centers. The workpiece is clamped between the headstock and tailstock. To improve the quality of grinding, the body rotates. When it comes into contact with the abrasive disc, excess material is removed in the form of metal dust shavings.

In addition to this technique, the so-called centerless cylindrical grinding machines have recently gained popularity. In them, the workpiece is placed on a working carriage and, on the one hand, is held by an auxiliary wheel, and the other is subjected to grinding with the main abrasive. In this way, high-quality fine machining of thin-walled cylinders or tapers can be carried out. The degree of pressing is regulated by an automatic system.

Additionally, it is necessary to take into account the following features that a cylindrical grinding machine possesses:

• the presence of a rotary table. With its help, it is possible to displace the workpiece relative to the abrasive disc in the horizontal and vertical plane;
• device of the feed mechanism. It can be an automated complex or its mechanical analogue. In the latter case, machines of this type are used for rough grinding;
• the possibility of fixing the workpiece in the centers, chuck. This parameter only applies to center-type equipment.

Currently, a large number of models of cylindrical grinding machines are produced. Therefore, in addition to choosing according to design parameters, it is necessary to take into account the technical and operational qualities of the equipment.

For grinding over the entire surface of the workpiece, the cylindrical grinding machine must have a mechanism for displacing the abrasive wheel. In this case, the longitudinal feeds of the abrasive and transverse parts are taken into account.

List of main technical characteristics

As an example, we can consider the operation of a standard model of a circular grinding machine 3M152. In it, the workpiece is positioned in the centers. Most of such equipment has a similar design.

It is best to conditionally divide the technical characteristics of the machine according to its nodes. Structurally, it consists of a workpiece clamping unit, a machining center (grinding head) and a control system. The average weight of such a machine is about 8 tons. Moreover, it has large dimensions, which makes special conditions for installation and operation.

Main technical parameters:

• the maximum permissible dimensions and weight of the workpiece to be processed;
• grinding diameters - minimum and maximum;
• distance from the headstock spindle axis to the work table surface.

Desktop characteristics:

• desktop offset - maximum length;
• manual acceleration and deceleration parameters;
• angles of rotation clockwise and counterclockwise;
• displacement characteristics by hydraulic system. This is necessary for processing massive parts.

The fixing of the part takes place between the headstock and the tailstock. They should be analyzed according to the following parameters:

• rotation frequency;
• for the tailstock, the offset of the quill.

In addition, the total power consumption of the equipment, the possibility of installing auxiliary structures and the parameters of the cooling system are taken into account. The presence of the latter is a mandatory requirement for industrial models of cylindrical grinding machines.

To maintain the machine in working order, it is necessary to periodically carry out preventive and repair work. It is especially important to apply lubricant to the moving parts of the equipment in a timely manner.

Cylindrical grinding methods

There are several techniques that can be used to perform external sanding. The choice depends on the desired result as well as the actual characteristics of the equipment.

The most common method is longitudinal processing. The workpiece is fastened in the centers. With the help of the drive of the headstock, rotation is given to it. At the same time, the feed mechanism provides longitudinal displacement of the workpiece relative to the abrasive wheel.

In addition to this method, modern cylindrical grinding machines can perform the following types of processing:

• deep. It is used for grinding short parts. Up to 0.4 mm of material can be removed in one pass. The main processing process is carried out by the conical part of the circle;
• mortise. With its help, you can effectively perform roughing or finishing grinding. To do this, set wide abrasive wheels. During machining, the part does not move relative to the tool;
• ledges. This is a combined type, combining creep and plunge-cut grinding. Ideal for removing excess material from workpieces with complex shapes.

Most models of cylindrical grinding machines can perform all of the above types of processing. It is only important to select the correct characteristics of the equipment in order to achieve the desired accuracy.

As an example, you can watch a video that shows the operation of a CNC cylindrical grinding machine:

Grinding (grinding) is a method of processing a part to specified dimensions. For this, abrasive materials applied to the grinding wheels are used. Portable cylindrical grinding machines for working on metal have many options, both a manual method and a method with CNC systems (3u10a, Studer series of machines, etc.).

Cylindrical grinding machines are widespread in manufacturing enterprises that manufacture products in large, medium, small series and even single copies. The universal cylindrical grinding machine is intended for grinding cylindrical and conical parts both inside and outside.

As a rule, the part goes to such a machine for finishing, which ensures high control accuracy in terms of parameters and surface finish.

1 Modifications

All cylindrical grinding machines have their own technological control and production accuracy:

• P - increased;
• B - high;
• A - especially high.

Cylindrical grinding machines, which are the most often found in industries, have the following designations:

• 3a423, 3a151,
• 3b12, 3b161, 3b153, 3b151;
• 3m151, 3m175;
• 3u10a;
• numerous series of Studer machines (S21, S31, S33, S41).

All modifications have an effective way to control dimensions when machining a part, including a method using CNC. Most of the machines allow you to process heavy and bulky parts on them.

There are also differences in the location of the workpiece. There are three modifications:

• center - the part is installed in the centers;
• cartridge - the workpiece is clamped in the cartridge;
• centerless - the part is installed on the processed surface.

1.1 Work nodes

The difference in technical characteristics for different sharpening models lies in power, distance between centers, permissible weight of the workpiece, maximum grinding diameter, and the width of the spindle head swivel range.

The devices are quite heavy, so a reinforced foundation must be provided for them.

Main working units:

• grinding headstock with grinding wheel spindle;
• knife support;
• cartridge (center);
• balancing device for grinding wheel;
• a device for dressing a grinding wheel;
• container with cutting fluid;
• clamps.

The universal cylindrical grinding machine can be equipped with a CNC, which greatly simplifies the control method and increases the accuracy of the work performed.

On such machines you can handle parts from almost any material:

• steel;
• cast iron;
• non-ferrous metal alloys;
• textolite;
• glass;
• special strength materials (cermets).

2 How it works

The workpiece to be machined is clamped in a chuck or mounted on the centers of the machine, and then, rotating, comes into contact with grinding wheels that have abrasive coatings. The machine table can be moved in a reciprocating direction and at the end of the completed pass the grinding wheel moves to the next predetermined cutting amount.

The longitudinal movement of the table is set by the CNC (via hydraulics) or manually (by rotating the handwheel). The grinding wheel head, which moves laterally, can also be controlled by CNC or manually. Abrasive wheels, with longitudinal and transverse movement, process the part first in the rough and then in the final version of grinding.

2.1 Machine 3m151

It is used for single, serial and large-scale machining of parts. In work on metal, 3m151 allows you to perform the following operations:

• grinding (plunge and longitudinal);
• external grinding of parts that have a conical or cylindrical shape.

Work can be carried out both in manual and in automatic (CNC) mode, while the method of controlling dimensions allows you to maintain high processing accuracy.

On the 3m151 machine, it is possible to process parts with a maximum diameter of 200 mm and a length of 700 mm, as well as a weight of up to 55 kg. The total weight of 3m151 (together with a cooling system and a set of electrical equipment) is 5600 kg with dimensions of 2170 × 2450x4605 mm.

2.2 Design features

The 3m151 machine has two tables (upper and lower). The first is placed in front of the bed and moves along the longitudinal guides, the second is used in the processing of conical parts and is rotated by a certain angle with a screw, followed by fixation with clamps. The way to control the dimensions, as well as to check them, consists in adjusting the scale and indicator mechanism located on the tables.

The hydraulics system at the 3m151 machine allows you to:

• manual blocking of table movement;
• longitudinal movement of the table (auto-reverse is activated at the end of the working stroke);
• quick approach / removal of the headstock;
• blocking the table when performing plunge-cut grinding;
• quill retraction.

With longitudinal and plunge-cut grinding on 3m151, full automation of the process is possible, which is carried out using a hydraulic drive with a clutch and a hydraulic motor. The quill, with a toothed rack, brings the tailstock to the workpiece for installation in the centers. This operation 3m151 allows you to carry out both manually and using hydraulics.

The tailstock 3m151 has a grinding wheel dressing device. If desired, this device can be automated, as an additional option when ordering from the manufacturer.

2.3 Universal machine 3b12

The 3B12 machine is a universal cylindrical grinding device and is used for grinding conical and cylindrical surfaces both inside and outside.

The presence of a turntable in 3B12 allows grinding of shallow conical surfaces.

For grinding steep tapered inner and outer surfaces, the 3B12 has a swivel headstock and a swivel headstock, which consists of two parts. The upper part can move on a slide relative to the lower part. Thus, on the 3B12 machine, it is possible to grind the end face of the part fixed in the chuck with the edge of the grinding wheel.

The 3B12 machine allows you to machine a part fixed in a chuck or installed in fixed centers.

On the machine 3B12 it is possible to carry out the following works:

• plunge-cut and longitudinal grinding;
• longitudinal grinding to the stop (automatic cross feed);
• grinding with the periphery of the grinding wheel of the end surfaces.

The 3B12 machine allows processing cylindrical surfaces with a diameter of 8-200 mm and a length of 100-500 mm, and holes 20-50 mm with a depth of up to 75 mm. Checking the accuracy of sharpening with a 3B12 machine is carried out using the appropriate scales for setting the processing parameters.

2.4 Special machine 3a423

Model 3a423 is intended for regrinding of connecting rod and main journals of crankshafts of internal combustion engines. Used by 3a423 in auto repair factories and repair shops. The 3a423 machine can grind cylindrical surfaces and cones that have a small slope angle.

When grinding the connecting rod journals on the 3A423 machine, the crankshaft is balanced by the weights moved on the chuck. The control system 3a423 has a mechanical, hydraulic and manual drive. It is possible to carry out grinding with automatic plunge-in.

The kinematic chains and hydraulic systems with which the 3a423 is equipped allow the following movements:

• rotate the spindle of the grinding head;
• rotate the workpiece;
• with the help of hydraulics, quickly move in / out the grinding headstock;
• move the table.

On 3а423, it is possible to process parts with a maximum total section of 580 mm and a length of 1600 mm (in the centers); 1450 mm (in cartridges), as well as weighing up to 150 kg.

The power of the electric motor of the main drive of the machine tool 3a423 is 11 kW. Machine dimensions 3a423 (in width, depth and height) - 5650 × 2530x1830 mm. Total weight - 7250 kg.

2.5 Model 3B161

The 3B161 machine is used in external grinding of cylindrical and conical (with a gentle bevel) surfaces.

Types of grinding on the 3B161 machine:

• longitudinal and milling (with manual control);
• longitudinal (in automatic cross feed mode);
• cut-in (all the way, in a semi-automatic cycle).

Model 3B161 allows you to install additional devices, according to which the accuracy of the work is checked by the method of active control of dimensions. This method is possible with a special configuration 3B161 and requires additional payment.

There is a modification 3B161, which does not have a hydraulic plunge mechanism. Plunge and longitudinal grinding on the 3B161 machine is carried out by the method of manual cross feed.

The maximum dimensions of the processed parts on the 3B161 machine are 280 mm in diameter and 1000 mm in length. The 3B161 machine has a wheel drive electric motor - 7 kW (980 rpm). Overall dimensions in length, width, height - 4100 × 2100x1560 mm, with a total weight of 4500 kg.

2.6 Universal semiautomatic device 3M175

The semiautomatic device 3M175 has an accuracy class P and is designed for grinding flat conical and cylindrical surfaces.

Semi-automatic grinding takes place in stationary centers. Swivel table top of the semiautomatic device 3M175 provides work with tapered surfaces.

The semiautomatic device 3M175 is easy to operate and maintain. Operations to move the table, turn on the rotation of the workpiece, cool and quickly feed the grinding wheel - are performed with one handle.

On the 3M175 machine, processing of parts with a size of 2800 mm with a diameter of 400 mm is permissible. The grinding area is defined by a diameter of 400 mm and a length of 2520 mm.

The overall dimensions of the 3M175 are 8310 × 3690x2135 mm with a total weight of 13850 kg.

2.7 Machine tools 3m175, 3a151, 3u10a, 3b153, 3b151

Models 3m175, 3a151, 3u10a, 3b153, 3b151 are used for external grinding.

On machines 3m175, 3a151, 3u10a, 3b153, 3b151, it is possible to install active control devices, therefore, a thorough check of all parameters when working on metal is carried out automatically. This control method allows us to produce quality products with a smooth and clean surface.

The 3u10a machine differs from the 3m175, 3a151, 3b153, 3b151 in particularly high precision when grinding the outer and inner cylindrical or conical surfaces.

Characteristics 3u10a:

• workpiece diameter - up to 100 mm;
• workpiece length - up to 180 mm;
• electric motor power - 1.1 kW;
• dimensions - 1250 × 1400x1690 mm;
• weight - 1850 kg.

2.8 Studer universal cylindrical grinders

Studer S41 is a machine equipped with a new generation of CNC controls. Studer has many special technical additions, such as a unique guideway system, high precision linear motor drives, a large selection of grinding wheels.

Studer S21 - Suitable for sanding workpieces with high quality control requirements. Can be fully automated. It is used for the manufacture of products for the aerospace industry, precision mechanics and hydraulics (pneumatics).

Studer S31 is widely used in the tool industry.

Studer S33 - has three grinding wheels that provide complete machining of the part at the highest level.

2.9 How it works cylindrical grinding machine 3K12? (video)

Nowadays, many important factories require the manufacture of precise parts with a fairly smooth surface. This work can be done using various abrasive techniques, including circular grinding equipment. Cylindrical grinding machines can be classified as metalworking tools. With their help, they make precise grinding of metal workpieces along the outer part. Structurally, tools of this type are very different from similar equipment.

Purpose of machines

The main purpose of such equipment is this is the processing of the outer parts of the part which has different shapes. For example, cylindrical, straight, or conical. Due to the fact that this equipment uses grinding and diamond circles, a fairly high accuracy of size and geometry, as well as a light roughness of the machined parts, is ensured. Most often, cylindrical grinding machines are used after the part has passed the first (heat or mechanical) treatment. Experts divide cylindrical grinding machines into a couple of types, there are conventional options and there are universal ones.

• A simple circular grinding unit processes parts with a small taper, no more than six degrees.
• Universal units can handle parts with a huge taper angle, this is possible due to the design features of these machines. The fact is that they can be used to rotate the headstock and grinding headstock. The latest models of cylindrical grinding units have characteristics that help them to work with workpieces that have a huge diameter and size. They are fully automatic and semi-automatic.

Specifications

Cylindrical grinding machine 3m151

This unit has been operating in our country for a very long time. It helps to machine cylindrical, discontinuous cylindrical parts, as well as the surface of various tapers at the highest level.

Due to its uniqueness, unit 3m151 helps to work with the most complex workpieces. The grinding method used in such a machine is called longitudinal or plunge-cut. The devices that are installed on this machine make it possible to fully control both the size of the workpiece and the process of the processing itself.

Additionally, you need to take into account the following subtleties that the circular grinding unit has:

• The presence of a turntable. Thanks to this table, the product can be displaced relative to the abrasive disc in the horizontal and vertical part;
• Feed mechanism device. It can be an automatic complex or its special analogue. In the latter case, units of this type are used for rough grinding.
• Possibility of fixing products in centers, chuck. This factor applies only to center-type equipment.

The unit helps the specialist to quickly work with products with a length of 700 mm and a diameter of 200 mm. The frequency with which the grinding wheel of the unit starts to rotate will be equal to 1590 min-1. It turns out that the speed of movement of the stage (which can be adjusted steplessly) will be 0.05-500 min-1. Recently, a huge number of models of such machines have been produced. Therefore, in addition to choosing according to standard parameters, you need to look at the technical and operational qualities.

Such cylindrical grinding units are of great benefit and now it is very difficult to do without them, they are required almost everywhere.