Self-test questions
1. What data is included in the designation of abrasive wheels and heads?
2. What are the characteristics of high precision abrasive wheels?
3. What are the advantages of segmented circles over solid ones?
4. What are the features of grinding wheels with an intermittent working surface?
5. Why is it necessary to test abrasive wheels for strength?
6. What techniques can be used to increase the strength of abrasive wheels?
7. How is abrasive wheels tested for strength?
8. What are the main causes of imbalance in abrasive wheels?
9. What are the consequences of grinding with unbalanced wheels?
10.What is imbalance?
11.What types of defects in abrasive wheels can be detected by external inspection?
12.Why is a cardboard spacer installed between the pressure flange and the grinding wheel?
3 Methods for grinding machine parts
3.1 External cylindrical grinding
External cylindrical grinding is used to process the outer cylindrical surfaces of machine parts. The diagram of the cylindrical grinding machine is shown in Figure 2.
there is a headstock 3, with an individual spindle drive. A tailstock 5 is installed on the right side of the table. It can be installed by moving along the guides at any distance from the headstock B
The grinding head 4, equipped with an individual drive, has only one radial (transverse Sp) movement. The table, together with the headstock and tailstock installed on it, has the ability to rotate around a vertical axis.
sometimes called the plunge method. Cutting pattern for external cylindrical grinding longitudinal feed method, used when the length of the processed surface is greater than the width of the circle, is shown in Figure 3.
Figure 3 - Scheme of external cylindrical grinding using the longitudinal feed method
The part, with a clamp attached to it, is installed in the centers.
The abrasive wheel is given a rotational movement (V). This is the main thing
movement that provides a given cutting speed. The angular speed of the circle is a machine specification and therefore is not regulated by the worker. The part is given a rotational movement, a peripheral speed, which determines the circular grinding feed Scr. For each revolution of the part, the table together with the part is a fraction of the width of the circle. This is how longitudinal feed (Spr) is carried out. After the circle has moved the length of the surface being machined, the spindle head
completion of removal of allowance and nursing, i.e. grinding without feeding to a depth until sparks (hot chips) disappear. As can be seen from the diagram
Parts longer than eight diameters are processed using a steady rest in order to reduce the elastic deformation of the part in the radial direction
mechanical engineering |
industry |
applies |
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preliminary, final and fine grinding, |
express, |
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power and depth grinding. |
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Draft |
grinding |
applies |
large-scale |
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production |
use |
blank In to |
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rough |
sanding is more economical |
turning and milling. Treatment |
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carried out at a grinding wheel speed of 50-60 m/s. Rough grinding |
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provided |
accuracy 8-9th |
quality and roughness |
surface Ra = |
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Pre-grinding performed after semi-finish blade processing before heat treatment to prepare the part for more precise processing. Preliminary grinding is carried out at Vк = 40 – 60 m/s. In this case, an accuracy of 6–9 quality and surface roughness Ra = 1.25 ... 2.5 are achieved.
Final sanding Performed, as a rule, after heat treatment with a cutting speed Vк = 35...40 m/s. Final grinding achieves an accuracy of 5 - 6 quality and a surface roughness of Ra = 0.2...1.2.
grinding |
apply |
achievements |
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geometric shape of the processed surfaces and roughness R = |
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0.025…0.1. For fine grinding, an allowance of up to 0.1 mm per diameter is left. |
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grinding |
carried out |
precision, |
machines circles |
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selected according to grain size, hardness and structure. Technological bases |
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thoroughly |
processing, |
For example, grinding. |
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For economic reasons, grinding is used in single or small-scale production and in the production of technological equipment.
High speed grinding - one of the methods of high-performance abrasive processing. High-speed grinding includes grinding with wheel speeds exceeding 35 m/sec. High-speed grinding has a number of advantages over conventional grinding. With increasing wheel speed, grinding performance increases, cutting forces decrease and
roughness |
processed |
surface, decreases |
error |
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processing, increases |
fortitude |
circle, shrinking |
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curing, the grinding coefficient increases. All this makes it possible |
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increase the minute feed while maintaining the requirements for quality and processing accuracy. For high-speed grinding, special machines with
increased |
established |
power, having |
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vibration resistance, with automatic balancing and wheel straightening, with |
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special devices for supplying coolant to the cutting zone, reducing |
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splashing liquid. In mechanical engineering, machines with the highest |
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speed |
grinding |
circle 60 m/sec |
Cylindrical grinders |
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3M162, KhShCh – 80, etc., centerless grinding machines 3M184I, 3M185I, 3Sh184I, |
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internal grinding SS – |
122, surface grinding |
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For high-speed grinding, only high-strength abrasive wheels are used |
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Power grinding(grinding) is used for peeling workpieces: |
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castings, forgings, |
rolled without preliminary blade processing. It |
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characterized |
high (over 80m/sec) |
speeds |
cutting, large |
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cutting is carried out |
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cylindrical grinding, centerless grinding, surface grinding |
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special (for example, pendulum) machines with main drive power |
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movement |
ceramic or |
organic |
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(bakelite) bond with grain size 63 – 250 and hardness from C2 to CT. For |
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For power grinding, wheels are used that work at the periphery or at the end. |
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In the latter case, segmented or intermittent circles are used. |
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power grinding achieves a sharp increase in labor productivity. The metal removal rate during power grinding can be 4 to 6 times higher than the metal removal rate during blade processing. The power grinding method can effectively remove an allowance of up to 7mm per side.
an abrasive wheel with a cutting part in the form of a conical surface (Figure 4). With this grinding method, the wheel is cut to the full amount of the allowance, processing is carried out in one double stroke of the table. Creep-feed grinding is also used for profile grinding, for grinding grooves and grooves as a whole.
Figure 4—Feature grinding scheme
Grinding of steep and short conical surfaces is shown in Figure 5. The part in this case is installed in a chuck.
Figure 5 - Scheme for grinding surfaces with a large taper angle
There are also designs of machines in which, to process conical surfaces, the spindle head rotates at a given angle and moves along the generatrix of the cone (Figure 6). The workpiece is installed in the centers.
Figure 6 - Scheme for grinding conical surfaces
Conical surfaces with a small taper angle are ground by rotating the table around a vertical axis along a non-bite (pattern 7). The part is installed in the centers.
Figure 7 - Scheme for grinding conical surfaces
External cylindrical grinding using the cross-feed (or plunge) method is used when the length of the ground surface is less than the width
abrasive wheel installed on the machine (Figure 8). In this cutting pattern |
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movement along the axis of the workpiece is excluded. Performance |
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processing increases. But this method has one very significant |
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The disadvantage is uneven wear of the circle across its width. Therefore more is required |
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frequent editing of the wheel to maintain the desired shape of its working surface. |
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Duty cycle |
grinding consists |
of four stages: plunging, roughing, |
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finishing and curing. At the plunge stage, grinding is carried out |
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with accelerated |
cross feed. During rough stock removal |
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gradually reduce the cross feed. At the nursing stage, the transverse |
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the wheel feed stops. At this stage, the quality of the processed product is formed |
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surfaces. |
modern |
improve |
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grinding by varying the rotation speed of the grinding wheel and the workpiece.
Figure 8 - Scheme of external cylindrical grinding using the cross-feed method
Grinding using the cross-feed method can also process shaped surfaces (Figure 9).
Figure 9 - Scheme for grinding shaped surfaces of bodies of revolution
The machine must be equipped with a device for dressing the wheel according to a given profile.
Very often in the drawings of stepped shafts, the perpendicularity of the shoulder and the journal associated with it. In this case, to fulfill the specified technical requirement, it is necessary to grind the neck and shoulder in one installation (Figure 10). To simultaneously grind these surfaces, use a wheel with a special dressing. The machine is selected in such a design that it is possible to rotate the grinding head around a vertical axis at an angle of up to 45 degrees. The wheel should be edited in two mutually perpendicular directions. If the neck being processed is short, then the feed is made in the direction perpendicular to the axis of rotation of the grinding wheel.
Figure 10 - Schemes for grinding the shaft journal and the end surface of the shoulder in one setup
Let's consider shape and dimensions of the layer section cut by abrasive grain, using the example of external cylindrical grinding (Figure 11). The part rotates at a speed Vd, which determines the amount of circular feed. Let us assume that the grain is cut to a depth t. At a small value of Scr, thin chips are cut off. The maximum chip thickness is significantly less than the depth of cut. The height of the roughness ridges is an order of magnitude less than t and the load on the grain is minimal. If you increase the rotation speed of the part, then the cross-sectional area
of cutting chips will increase. With a further increase in Scr, each grain will cut chips with a thickness equal to t and a length equal to the length of the cutting path (CS) of the grain. An increase in the angular velocity of the abrasive wheel (Vcr) will lead to a decrease in the cross-section of the chips cut by the grain, and, consequently, to a decrease in the roughness of the machined surface. The use of more open wheel structures, in which the distance between the grains is greater, all other things being equal, will lead to conditions similar to an increase in circular feed.
Figure 11 - Scheme of cutting allowance for external cylindrical grinding
cylindrical, conical and shaped holes. Grinding of holes is carried out in the following ways:
o with a rotating part fixed in a chuck; o with a stationary part;
o with a rotating loose part.
The first method is more often used for axisymmetric parts (bushings, sleeves, gears, etc.) using cartridge-type internal grinding machines (3K225A, 3K227V, 3K228A, 3K229V, etc.)
For grinding holes in large, heavy, asymmetrically shaped and body parts, the second grinding method is used on planetary internal grinding machines
The third method is used for grinding bushings, sleeves, etc., with a pre-ground outer diameter on centerless grinding machines.
The most common is the first method. Grinding the holes can be done with using longitudinal feed(passing) or cutting in. Figure 12 shows a diagram of internal grinding of a through hole. With this method, the part fixed in the chuck is given a rotational movement, which determines the amount of circular feed. The abrasive wheel rotates around its own axis from an individual drive with a large
number of revolutions, makes a reciprocating motion Sp along the axis of the hole being machined and for each double stroke moves in the radial direction Sp by a given amount of transverse feed. Longitudinal feed is expressed as a fraction of the wheel width (0.6 – 0.8 for roughing and 0.2 – 0.3 for finishing). Cross feed is set within 0.003 – 0.015 mm.
Figure 12 - Scheme of internal grinding by longitudinal feed of a rotating part
The directions of rotation of the circle and the part must be opposite. The rotation speed of the part should be 0.015 – 0.03 of the grinding wheel speed. The height (width) of the circle is taken to be approximately equal to 0.8 of the length of the hole being machined. The diameter of the circle should be within 0.8 - 0.9 of the hole diameter. The larger the diameter of the circle, the larger the area of the cutting zone, the higher the productivity, but at the same time the radial cutting force increases and the possibility of burns increases. If a circle of small diameter is selected, then to ensure a cutting speed of 10 - 20 m/sec, a drive is required that provides tens and hundreds of thousands of revolutions per minute.
On semi-automatic internal grinding machines, holes are processed as follows. After securing (manually) the part, the grinding wheel approaches the part at a rapid feed, then the longitudinal feed automatically changes and is set in accordance with the technology characteristic of rough grinding. The hole is ground until
will remain |
fine grinding. Then |
grinding |
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is displayed |
from the hole |
automatically straightened with diamond |
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pencil. |
Finish grinding is performed at a lower longitudinal |
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speed |
rotation of the part. After |
removal of allowance and |
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subsequent nursing, the grinding wheel is removed from the hole and the rotation of the part stops.
Plunge grinding used for processing short (compared to the width of the circle), blind and shaped holes.
The drawings of some parts, for example, gears, stipulate a strict tolerance for the perpendicularity of the end and the hole associated with it. To process such parts, it is necessary to use internal grinding machines that have an additional spindle for grinding the ends (Figure 13).
The universal cylindrical grinding machine OSH-518F2 is used for cylindrical grinding of external cylindrical surfaces. The cylindrical grinding type of machines is used in mechanical engineering, instrument making, machine tool manufacturing, and in the production of tools in industries for small-scale and mass production. Final grinding using cylindrical grinding machines can be achieved with a size grade of 6-7 and a surface roughness of 0.32 microns.
Technical characteristics of OSH-518F2 |
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| Characteristic | Meaning |
| Accuracy class according to GOST 8-82 | IN |
| Largest diameter of the workpiece, mm | 150 |
| Maximum length of the workpiece, mm | 400 |
| Maximum grinding length, mm | 400 |
| Distance from the axis of the headstock spindle to the table mirror - center height, mm | 110 |
| Maximum mass of the processed product, kg | 20 |
| Maximum angle of rotation of the upper table clockwise, degrees | 3 |
| Maximum angle of rotation of the upper table counterclockwise, degrees | 3 |
| Grinding head, rotation, degrees | ±30 |
| Grinding wheel diameter - largest/smallest, mm | 400 |
| Grinding wheel diameter - landing, mm | 127 |
| Grinding head: maximum height of the installed wheel, mm | 25 |
| Headstock: Turn, degrees | 30 |
| Front headstock: Product rotation speed (stepless regulation), rpm | 100…1000 |
| Headstock: Grinding headstock spindle motor, kW | 2.2 |
| Overall dimensions of the machine (length x width x height), mm | 2500x2800x1900 |
| Weight | |
The machine has manual and automatic control from a command controller. The machine has a layout with a moving table on which the workpiece is mounted and the grinding headstock moves perpendicular to the center axis relative to the workpiece. The workpieces are located in the centers of the headstock and tailstock or in the chuck.
The grinding working area is protected by an open-type protection; the front wall of the protection has a movable opening door with plexiglass.
The workpiece headstock and the rear headstock are mounted on the upper working surface of the movable table. The grinding head moves along linear rolling guides via a ball screw drive. The headstock of the product can be manually rotated through an angle of 90º, the grinding headstock has two spindles for external and internal grinding, and also has the ability to manually rotate through an angle of ±30. The internal grinding spindle is rotary. The upper table can be rotated at an angle (3º clockwise and -3º counterclockwise) and is based on the lower table, which in turn moves along the sliding guides of the bed.
Dressing of the periphery and end of the grinding wheel is carried out using diamonds in the frame of the dressing mechanism installed on the upper table due to the longitudinal movement of the table and the transverse movement of the grinding wheel (linear interpolation along two coordinates).
The hydraulic equipment is made as a separate unit and is installed at the rear of the machine, and the cooling system is on the left. The electrical cabinet is located on the right side of the machine.
In front of the machine, on the electrical cabinet, there is a combined control panel with a Siemens operator panel and a machine console with electronic flywheels, a joystick and control buttons.
When grinding, a water-based coolant is used; the coolant is cleaned using a magnetic separator and a conveyor filter. Coolant is supplied to the processing zone under pressure P = 2 atm, pump capacity Q = 30 l/min.
Non-contact sensors from Balluff.
Low-voltage equipment from Siemens.
As feedback, linear displacement transducers from Fagor are used.
The universal cylindrical grinding machine OSH-510F2 with an internal grinding spindle is used for cylindrical grinding of external and internal cylindrical and conical surfaces. It is used in small-scale and serial machine-building production. Final grinding using cylindrical grinding machines can be achieved with a size grade of 6-7 and a surface roughness of 0.32 microns.
The kinematics of the machine provides the following movements:
Technical characteristics of OSH-510F2 |
|
|---|---|
| Characteristic | Meaning |
| Limit dimensions of the installed workpiece, mm: - at centers: diameter / length - in the cartridge: diameter / length | 100/250(300) 80/160 |
| Grinding dimensions, max, mm: - at centers: diameter / length - in the chuck for external grinding: maximum diameter / length - in the chuck for internal grinding: maximum diameter / length | 100/225 80/160 40/50 |
| Workpiece weight, max, kg - in centers/chuck | 7/5 |
| Center height, mm | 80 |
| Grinding wheel dimensions, max, mm - for external grinding: outer diameter/height/inner diameter - for internal grinding: maximum outer diameter/height | 250/25/76 |
| Rotation angle, max, degrees: - top table clockwise/counterclockwise; - headstocks of the product when processed in a chuck clockwise/counterclockwise; - grinding head; | 3/3 30/90 |
| Main drive power kW | 2,2 |
| Spindle power for internal machining kW | 0,75 |
| Rotation speed of the internal grinding spindle, rpm | 8000…30000 |
| Part rotation speed, rpm | 10…500 |
| Overall dimensions of the machine, mm, no more | 1800x2150x1900 |
| Weight of the machine with attached equipment, kg | 2000 |
| Precision processing parameters: - deviation from constant diameter over a length of 225 mm in longitudinal section when processing in centers, µm - roundness tolerance when processing in centers - roundness tolerance when machining in a chuck | GOST 11654-90 for machines of class “B”: 4,0 |
| Roughness: - cylindrical external, Ra - cylindrical internal, Ra - flat end, Ra | 0,32 0,32 0,63 |
Manufacturer of universal profile grinding machine 395M - Leningrad Machine Tool Plant named after. Ilyich, founded in 1924.
Since 1984, the Ilyich plant has been part of Association of precision machine tools as the parent company, and since 1993 registered as St. Petersburg Precision Machine Tool Manufacturing Plant, SPZPS.
Rice. 38. Cylindrical grinding methods:
a - with longitudinal feed, b - deep, c - plunge, d - successive plunges, d - combined
On external cylindrical grinding machines, the workpiece is mounted on centers and driven into rotation by the headstock spindle. To carry out circular external grinding, the following movements are necessary: rotation of the wheel or the main cutting movement, rotation of the part - circular feed of the part, reciprocating movement of the part (or wheel) along its axis - longitudinal feed, feed to the grinding depth.
External cylindrical grinding is carried out in several ways:
In some cases, the circle is imparted an additional axial oscillatory movement with a small amplitude - an oscillating movement.
The B-88 universal cylindrical grinding machine is designed for external and internal grinding of cylindrical and conical surfaces of parts requiring dimensions, as well as for grinding the flat ends of round parts in tool and repair shops in conditions of single and small-scale production. The coin product to be processed can be installed in fixed centers, a three-jaw chuck or collet clamp, as well as with the help of additional devices.
On the B-88 cylindrical grinding machine, you can grind external and internal cylindrical, conical surfaces and end surfaces by longitudinal or plunge grinding, installing a grinding wheel on the right or left end of the grinding spindle, turning the upper table, workpiece headstock or grinding headstock slide.
The main material of the products to be processed on the machine is hardened carbon steel, however, with the use of appropriate abrasive or diamond wheels and the selection of the required technological modes (within the technical specifications of the machine), it is possible to process products made of hard alloys and other materials.
The machine was developed in 1966.
Developer: Leningrad Machine Tool Plant named after Ilyich, Leningrad.
Manufacturer: Leningrad Machine Tool Plant named after Ilyich, Leningrad.
Main parameters and dimensions according to GOST 11654.
The B-88 cylindrical grinding machine has a rotary table. This makes it possible to grind not only cylindrical, but also flat conical surfaces.
Thanks to the rotatable front and swivel grinding wheel, steep conical external and internal surfaces can be sanded.
The grinding head consists of two parts. The upper part of the grinding headstock can move relative to the lower part (upper slide). This makes it possible to grind the end of the part fixed in the chuck with the periphery of the grinding wheel.
The machines are controlled using handles and buttons located on the front wall of the frame and on the control panel.
Connecting and landing bases for the V-88 grinding machine
Photo of the B-88 cylindrical grinding machine
Photo of the B-88 cylindrical grinding machine
Location of controls for the V-88 grinding machine
Product drive. The headstock spindle or drive faceplate is rotated by the engine through a two-stage V-belt drive and has two speeds.
The friction clutch is interlocked with the brake in such a way that when it is turned off, the spindle is braked.
The grinding wheel is driven electrically. engine using a V-belt drive. To maintain the required speed of the grinding wheel as it operates, the use of replaceable pulleys on the electric shaft is provided. engine.
Longitudinal feed is carried out using a manual drive from a handwheel through two pairs of spur gears and a rack and pinion gear.
For precise longitudinal movements of the table required for face grinding, a fine feed mechanism is included in the drive chain.
Transverse feed of the grinding headstock is also carried out manually using a worm pair and rack and pinion gear
For fine feed there is a mechanism similar in design to the mechanism for thin longitudinal feed.
The main parts of this unit are the bed itself and the cabinet, which have a T-shape in plan. The internal cavity of the cabinet is used to install starting electrical equipment, for access to which there is a window in the front wall of the cabinet that is closed with a lid.
On the top of the frame there are front flat and rear prismatic guides for installing the table. The guides are equipped with four pockets for lubricant, which is supplied to the rubbing surfaces by means of spring-loaded rollers (parts 107 and 108).
On the front wall of the frame there is a processed plate for fastening the longitudinal and transverse feed mechanisms.
There is a machined area on the back of the upper wall of the bed to install the grinding head.
The table assembly consists of a lower table with guides for moving along the frame and an upper table for turning the table.
The lower table is molded integrally with the visors covering the frame guides when the table is in its extreme positions. A rail is screwed to the bottom of the table to move the table along the frame guides.
On the front of the table there is a processed plate for attaching longitudinal movement stops.
On the upper plane of the lower table there are plates - supports for the upper table with a rotation axis in the middle; Along the edges there are pads for clamping and the upper table. On the right block there are two scales for counting the angles of rotation of the upper table: one - in degrees, the second - in taper values, referred to 100 mm of the length of the product.
To accurately set the angle of rotation of the upper table, use a screw (part 106).
The upper table is made with guides for installing the front and rear headstocks, which are fastened to the guides using a T-shaped groove.
The headstock with its base is installed on the guides of the upper (rotary) table and is attached to it using a block (part 150) and a bolt (part 154). The headstock body can be rotated around its axis (part 144).
After turning to the required angle, measured on the scale marked on the base of the headstock, the headstock body is secured using two groove bolts (parts 152 and 153).
To accurately set the headstock body to the zero position, as well as to rotate it to the required angle, use adjustable stops (part 147).
To drive the headstock, a flange electric motor mounted on a bracket (part 014) is used. By moving the bracket with el. The engine regulates the tension of the drive belt.
The headstock drive chain includes a friction clutch, the structure and operation of which is as follows:
On the clutch shaft (part 126), connected to the electric motor shaft, a two-stage drive pulley (part 129) with a brake drum (part 128) having an internal conical surface, to which the cone is pressed by the force of the spring (part 140) is mounted on ball bearings (part 127), connected by two keys to the shaft (part 126).
When using the handle (D61-1) to turn the sector (part 134) engaged with the teeth of the pressure cup (part 125), the latter, turning around the bushing (part 124), moves axially to the right and acts on the cone (part 127), which as a result comes out of contact with the drum (part 128).
At the same time, under the action of the spring (part 137), the brake lever (part 136) comes into operation, which slows down the drive pulley, and with it the headstock spindle.
The movement of the pressure cup (part 125) in the axial direction is achieved due to the presence of four wedge cams on its left end.
The transmission of rotation from the drive pulley (part 129) to the spindle pulley (part 104) is carried out using a V-belt, when rearranged on the pulley steps, the spindle can be given two different rotation speeds.
The design of the headstock provides the ability to work both with a rotating spindle (work using centers or a collet clamp), and with a stationary spindle and a rotating drive faceplate.
Drawing B 88.03.001 in section along AA (option-1) shows the position of the parts in the case of working with fixed centers.
When working with a rotating spindle (using centers or a collet clamp), the following must be done:
The design is typical for cylindrical grinding machines; it is attached to the rotary table guides with a groove bolt. The quill retraction is lever-type and is carried out using a handle (part 012). The quill is pressed against the product by a spring. A screw (part 105) is used to push out the center.
The quill can be secured in a certain position using the handle (D61-4)
The mechanism is driven manually and is located on the front wall of the frame. The grinding head is installed on the upper plane of the caliper (part 011), which moves along the guides of the rotary plate (part 012).
The latter, together with the support and the grinding head, can be rotated at an angle of ±45° relative to the bottom plate (part 013), mounted on the bed plate.
The support with the grinding head is moved by rotating the flywheel (part 015) mounted on the shaft (part 101).
A worm (part 128) is installed at the rear end of the shaft, working in tandem with a worm gear (part 019) mounted on the lower end of a rack and pinion gear (part 132), which meshes with the rack (part 131).
The feed amount is measured by the dial ring (part 112), which sits loosely on the flywheel disk (part 113). For one revolution of the flywheel, the amount of movement of the caliper is 0.75 mm (reduction in the diameter of the product by 1.5 mm), the price of one division of the dial is 0.0025 mm.
To count the fine feed value, use the second dial, located in front of the main one, with a division value of 0.001 mm.
Fine feed is carried out using a handwheel (part 016), a worm (part 120) and a worm gear (part 017), freely sitting on the shaft (part 101).
Switching the drive from coarse feed to fine feed and vice versa is carried out by a handle (D 61-3) connected to a cam (item 103) that controls the rocker (item 105).
The link with its bevels acts on the expansion pins (parts 114 and 118), which, moving under the action of the link, enter with wedge-shaped ends into the cuts of the friction rings (parts 111 and 117), causing the latter to expand.
Thanks to this, the limb ring (part 112) or the worm gear (part 017) are connected to the shaft (part 101).
In drawing B 88.05.001 the parts are shown in the position corresponding to the included fine feed, i.e. the friction ring (part 117) is released and the worm gear (part 017) is connected to the shaft (part 101), and the dial ring (part 112) can freely rotate around the disk (part 113). To fix the dial ring (part 112) in the zero position, use the valve (part 141), which must be moved to the right using the handle (D 61-2) so that the cracker (part 143), fixed to the dial ring, entered the groove of the valve.
To turn off fine feed and turn off coarse feed, you need to move the cam (part 103) using the handle (D 61-3) to the position shown by the dash-dot line.
In this case, the rocker (part 105) will move to the right, compressing the spring, the pins (parts 114- and 118) will take a position in which the worm gear will be released, and the limb ring will be connected to the shaft (part 101).
After this, if the limb ring was fixed, move the valve to the extreme left position.
Designed to move the table along the bed guides and is attached to the left side of the front wall of the bed.
The movement of the table is carried out using a flywheel (part 013) through gears (parts 102, 107, 108, 110) and a rack and pinion gear (part 111), coupled with the table rack.
For smooth table movements in the case of face grinding, a fine longitudinal feed device is provided, similar in design to a similar device for transverse feed.
Fine longitudinal feed is carried out by a handwheel (parts 05, 016); turning on the fine feed is done using the handle (D 61-3; 48x8) by moving it to the position shown in drawing B 88.06.001 with a dash-dot line.
On the front side of the mechanism panel there is a stop (part 113) that limits the movement of the table.
It is installed on the upper plane of the cross-feed mechanism support and secured to it with two groove bolts (part 112).
The spindle head housing has a platform for installing a sub-motor plate (part 013) with an electric motor.
The transmission of rotation from the electric motor to the spindle is carried out by two V-belts.
To maintain the required peripheral speed of the grinding wheel as it operates, replaceable electric motor pulleys are provided. When working with a new grinding wheel on the shaft el. The engine must be fitted with a pulley dia. 70 mm and only when the circle is actuated to a diameter of 190 mm can a pulley dia. 92 mm.
It is strictly forbidden to install on email. engine pulley with a diameter of 92 mm when working with a new circle having a diameter of more than 190 mm. An exception may be made for wheels intended for high-speed grinding.
The spindle supports are two adjustable bimetallic plain bearings. Axial play of the spindle is selected by a double-row thrust ball bearing mounted at the rear end of the spindle.
Oil is supplied from the crankcase to the spindle bearings using lubricating rings.
Oil is poured into the crankcase and headstocks through the plug (part 111) to the level of the marks and oil indicators located on the front wall of the headstock.
The grinding wheel is protected by a guard (part 014).
Email The engine and drive belts are covered with a casing.
Installed as needed in place of the grinding headstock B 88.07.001.
The headstock body has a split boss in front for installing a grinding spindle. dividing, there is a platform at the rear for the electric motor. The transmission of rotation from the electric motor to the spindle is carried out by a flat cotton paper belt.
The electrical equipment of the machine is designed for connection to an alternating current network with a voltage of 220/380 volts and consists of:
The machine's electric motors are started using the universal switch UP-5312 in the following sequence: first, the electric motor is turned on. engine 1M (1aM), then alternately 2M and 3M.
Power supply local lighting lamps are produced through a step-down transformer TPB-50.
| Parameter name | 3У10А | B-88 |
|---|---|---|
| Main settings | ||
| Accuracy class according to GOST 8-82 | A | |
| Largest diameter of the installed product, mm | 100 | 140 |
| Maximum length of the installed product (RMC), mm | 160 | 180 |
| Maximum grinding length, mm | 140 | 180 |
| Largest grinding diameter, mm | 0..40 | |
| Smallest grinding diameter, mm | ||
| Recommended grinding diameter, mm | 3..15 | |
| Largest diameter of the hole to be ground, mm | 40 | |
| Recommended hole grinding diameter, mm | 3..15 | 25..50 |
| Maximum length of hole grinding, mm | 50 | |
| Distance from the axis of the headstock spindle to the table mirror - center height, mm | 120 | |
| Maximum weight of the installed product, kg | 1 | |
| Height of headstock centers above table, mm | 100 | 95 |
| Height of centers above the machine sole, mm | 1070 | |
| The largest diameter of the clamping chuck, mm | 100 | |
| Machine bed and table | ||
| Maximum longitudinal movement of the table, mm | 200 | |
| Maximum number of double table moves per minute, mm | 30 | |
| Minimum table travel between stops, mm | 1,5 | |
| Manual slow movement of the table per revolution of the flywheel, mm | 0,176 | |
| Manual accelerated movement of the table per revolution of the flywheel, mm | 2,5 | |
| Speed of automatic table movement (from the hydraulic system), m/min | 0,025..1,0 | No |
| Maximum angle of rotation of the upper table clockwise, degrees | 6 | 10 |
| Maximum angle of rotation of the upper table counterclockwise, degrees | 7 | 90 |
| Upper table rotation scale division value, deg | ||
| Scale division of the upper table (taper), mm/m | ||
| Grinding head | ||
| Maximum movement of the grinding head along the feed screw, mm | 100 | 80 |
| Displacement of the grinding head during rapid approach, mm | 15 | No |
| Angle of rotation of the grinding head clockwise, degrees | 30 | 45 |
| Angle of rotation of the grinding head counterclockwise, degrees | 30 | 45 |
| Time for rapid approach of the grinding head, s | 3 | No |
| Grinding wheel according to GOST 2424-67 | PP250x20x76 | 250 x 25 |
| Grinding wheel wear in mm per diameter | 80 | |
| External grinding spindle rotation speed, rpm | 2800 | |
| Jog feed - periodic feed with table reversal, mm | 0,00125 | |
| Manual jog feed - periodic feed at the moment of table reverse, mm | 0,00125 | No |
| Automatic jog feed - periodic at the moment of table reverse, mm | 0,0025..0,01 | No |
| Maximum stroke of automatic feed, mm | 0,25 | No |
| Transverse feed dial division price, mm | 0,0025 | 0,0025 |
| Fine cross feed dial division price, mm | 0,001 | |
| The amount of transverse movement of the grinding head per one revolution of the flywheel, mm | 0,5 | 0,75 |
| Maximum movement of the grinding head along the microfeed chain, mm/rad | 0,05 | |
| Speed limits of mortise microfeed, mm/min | 0,01..0,1 | No |
| Speed of fast installation movement of the grinding head, mm/min | No | |
| End of the grinding spindle according to GOST 2323-67 (taper 1:5, nominal diameter), mm | 32 | |
| Internal grinding attachment | ||
| The largest diameter of the workpiece installed in the chuck, mm | 60 | |
| Maximum length of the hole to be ground, mm | 85 | |
| Diameter of internal grinding head, mm | 20..45 | |
| Maximum width of the internal grinding head, mm | 16 | |
| Speed of internal grinding spindle | 40000..80000 | |
| Headstock (product headstock) | ||
| Product rotation speed (stepless regulation), rpm | 85..1000 | |
| 30 | ||
| Angle of rotation of the chuck clockwise, degrees | 90 | |
| Headstock spindle cone according to ST SEV 147-75 | Morse 3 | |
| Tailstock | ||
| The amount of retraction of the tailstock quill by hand, mm | 15 | |
| Tailstock quill spindle cone according to ST SEV 147-75 | Morse 2 | |
| Drive and electrical equipment of the machine | ||
| Number of electric motors on the machine | 7 | 4 |
| Grinding head spindle electric motor, kW (rpm) | 1,1 | 0,6 (2800) |
| Product drive electric motor, kW | 0,245 | 0,18 (1400) |
| Electric motor driving the internal grinding spindle, kW | No | 0,4 (2800) |
| Table drive electric motor, kW | 0,245 | No |
| Hydraulic pump electric motor, kW | 0,75 | No |
| Magnetic separator electric motor, kW | 0,06 | No |
| Paper pulling motor kW | 0,18 | No |
| Electric motor of the cooling system pump, kW | 0,12 | 0,125 (2850) |
| Overall dimensions and weight of the machine | ||
| Overall dimensions of the machine (length x width x height), mm | 1250 x 1400 x 1690 | 1140 x 920 x 1350 |
| Weight of the machine with electrical equipment and cooling, kg | 1980 | 580 |
