Boring machines are designed for processing parts in a single and batch production. These are versatile machines, which can be used for rough and fine boring of holes, turning of outer cylindrical surfaces, ends of holes, drilling, countersinking, reaming, milling of planes, threading and other operations. A wide variety of different types of processing performed on boring machines allows, in some cases, to carry out complete processing of a part without rearranging it to other machines.

Depending on the nature of the operations performed, the purpose and design features, boring machines are divided into universal and specialized. In turn, universal machines are divided into horizontal boring, jig boring and diamond boring (finishing boring). For all types of machine tools, the most important parameter that determines all the main dimensions of the machine is the diameter of the boring spindle. A characteristic feature of boring machines is the presence of a horizontal spindle, which moves the axial feed. A cutting tool is mounted in the spindle: a boring bar with cutters, a drill, a countersink, a cutter, a tap, etc.

The shaping movements in boring machines are spindle rotation and feed movement. The feed is communicated to either the tool or the workpiece, depending on the processing conditions. Auxiliary movements are the positioning movements of the spindle head in the vertical direction, the movement of the table in the longitudinal and transverse directions, the movement of the rear rack with a steady rest, the movement of the steady rest on the rack, etc.

Figure 39 shows general form horizontal boring machine. On the bed 1 rack installed 2 , on the vertical guides of which the spindle head is mounted 3. In its body there are mechanisms that carry out the main movement and feed. The spindle of the gearbox is hollow, a faceplate is fixed on it 4. A caliper is installed in the radial guides of the latter 5 carrying a cutter. A boring spindle is mounted inside the hollow spindle 6. If necessary, the end of the boring bar is inserted into the tapered hole of the latter, the left end of which is held in the steady rest 7 rear rack 8. The steady rest is located coaxially with the spindle and can be moved in the vertical direction synchronously with the headstock.

The table is used for setting and fixing the workpieces. , consisting of three elements: sled 10, moving along the bed 1 , carriages 11 , having a feed in the transverse direction and a rotary work table 9 .

The main movement is the rotation of the faceplate or boring spindle. The feed movement, depending on the nature of the processing, is received by a part (table) or a tool (support) 5 , boring spindle or headstock.

The jig boring machine is designed not only for processing holes with high precision, but also for obtaining accurate center-to-center distances. Linear dimensions and center-to-center distances can be measured on the machine. The spindle and machine table have independent drives. The spindle is driven by an adjustable DC motor.

Fig. 39. General view of the universal horizontal boring machine

Figure 40 shows a vertical diamond boring machine designed for fine boring of the cylinder bores of an automobile or tractor engine block with diamond tools or carbide cutters. This machine has a massive, rigid structure that reduces vibration from high-speed machinery.

Fig. 40. Diamond boring machine

On the foundation slab 1 the curbstone is mounted 2 , and on it - a vertical bed 3. There are T-slots on the front of the plate to secure the table 4. On the slab inside the curbstone 2 an electric motor is installed to drive the main movement. Pumps for coolant and lubrication, as well as electrical equipment are installed inside the cabinet. Inside the bed 3 gearboxes of speeds and feeds are placed, and in front, on its outer upper part, a spindle head is fixed 5 ... On two straight guides 6 vertical bed can move bracket 7 with spindle 8.

From the electric motor through the V-belt transmission, gearbox and flat-belt transmission, the machine spindle with boring bar receives six different frequency values. Adjustment of the spindle with boring bar to different rotational speeds is carried out using replaceable gear wheels of the gearbox.

The feed box is also an independent unit, mounted inside the frame in the upper part of it. In addition to the mechanism for switching the working feeds of the spindle with a boring bar, the feed box contains mechanisms for rapid traverse and automatic switching of the spindle from rapid traverse to the working feed, as well as to rapid return to the initial vertical position.

Using the rotary tables and other accessories supplied with the machine, you can also machine holes specified in the polar coordinate system, inclined and mutually perpendicular holes, and grind end surfaces.

The jig boring machine is equipped with optical devices that allow counting the whole and fractional parts of the coordinate size. The machine can be used both in tool shops and in production shops for precise processing of parts without special equipment. Under normal operating conditions, the machine provides the accuracy of setting the center-to-center distances in a rectangular coordinate system of 0.004 mm and in a polar system - five arc seconds.

Drilling holes in a part with precise axis placement does not necessarily require drilling machine... Drill and some milling work can be done with only one boring machine.

What is this machine and what is it for?

Boring machines belong to the group of boring machines and are intended for processing large body parts that cannot be processed in any other way. In addition to drilling and milling the end surfaces, which were mentioned earlier, on these devices you can perform:

• boring;
• countersinking;
• centering holes;
• threading;
• turning and trimming of ends.

In addition, a boring machine can be useful for accurately measuring and marking out the linear dimensions of the workpiece. For example, you can quickly measure the center-to-center distances of the axes of several holes without resorting to the use of special devices and fixtures.

Types of boring machines

• A horizontal boring machine that is used for roughing and finishing workpieces large sizes... It has a horizontal spindle. Its main movement is the translational-rotational movement of the spindle relative to its axis. Auxiliary movements: vertical movement of the spindle headstock, movement of the table in two coordinates, movement of the rear rack and steady rest. As with any other, the horizontal machine has the ability to adjust the required value of speed and feed.
• which is used in cases where you want to achieve the maximum accuracy of the hole or group of holes. For successful drilling, the coordinate machines are equipped with all necessary fixtures... For example, each such machine has a rotary table for machining holes in a polar coordinate system or when tilting.

Popular machine models are: 2A78, 2A450, 2435P, 2620 and 2622A. In addition, some models are additionally equipped with stands and digital display devices (DRO), which simplify and speed up the work.

Numerical and alphabetic designation

According to standard classification the boring machine belongs to the drilling group, which is indicated by the first number "2" in the model name. The numbers "4" and "7" indicate that the device belongs to coordinate boring and horizontal boring metal-cutting machines, respectively.

Letters between numbers indicate upgrades relative to the base model. For example, the basic model of the 2A450 machine is 2450.

The letters after the numbers indicate accuracy. For example, 2622A is a particularly high precision boring machine, and 2435P is an increased one.

The two numbers at the end of the name indicate the maximum cutting diameter.

Specifications

To choose a boring machine for processing a specific type of part, you need to pay attention to the main technical characteristics and. These include:

1. The largest diameter of the bore hole and the face to be turned. For example, for a horizontal boring machine model 2620, these are 320 and 530 mm. Accordingly, it is impossible to machine a hole or end face larger than these dimensions.
2. Dimensions (edit) work surface tables, which should be selected depending on the dimensions of the workpiece.
3. Engine power. This characteristic affects the further choice of power, speed and feed for machining a part.
4. The maximum weight of the work piece. For example, the jig boring machine model 2E440A has a weight limit of 320 kg.
5. Machine dimensions. In a production environment, no one would pay attention to this characteristic. But if you choose a machine for work at home, then you need to take into account the maximum length, width and height, since a too large machine will not fit, for example, in a garage room.

The search for the most rational designs of devices, combining small dimensions with ease of assembly and adjustment, led to the widespread use in the nodes and mechanisms of devices of complex structures, boards, brackets and other parts with the presence in them a large number holes of 1 and 2 classes of accuracy with tight tolerances not exceeding 0.01-0.02 mm, on the relative position of the axes of the holes. The simplest and most reliable solution to the problem of machining conjugate systems of precise holes is provided by the use of the coordinate boring method.
The development of this method and the creation of domestic jig boring machines were one of the critical factors that contributed to the achievement of very large successes in the field of precision instrumentation. Distinguished by high accuracy and productivity, jig boring machines, along with their wide use in tool shops, have found application in the production shops of instrument-making plants. Currently, the domestic machine tool industry equips the instrument-making industry with high-quality precision jig boring machines, however, along with domestic equipment, our factories also operate various models of imported jig boring machines ( processing centers ).

Application of various kinds auxiliary and setting devices allows you to expand the capabilities of jig boring machines and widely use them not only for tool work (stamps, molds, machine tools), but also for processing complex and precise parts in single and small-scale production.
There are two main types of jig boring machines:
- single-column machines whose table receives two mutually perpendicular displacements

2E450; 2E450AF10; 2E450AF30) which can be purchased from the LLC "Machine World" company;
- gantry machines, the table of which receives a longitudinal movement, and the spindle group, mounted on the cross member, receives a transverse movement.

According to the method of counting coordinates, the machines are divided into 3 groups:

1) Machine tools, on which the coordinates are read using a ruler, lead screw, dial and vernier in combination with the so-called correcting device, which corrects the inaccuracy of the screw pitch along its entire length. The use of the core fixture allows the use of large-sized machines with sufficient accuracy.

2) Machine tools, the coordinates of which are measured by end measures and indicators. The lead screws of these machines are not a measuring instrument, but only serve to move the table. The machines of this group are manufactured only as single-column machines.

3) Machine tools, the coordinates of which are measured on exact scales in combination with an optical device. These machines are a more advanced type of boring machines.

To work on jig boring machines, devices and accessories are used that increase the versatility of the machines and expand their technological capabilities. Depending on their purpose, they can be divided into the following groups:

Installation devices. The main purpose of these devices is to install and fasten parts. This type of device includes: squares, rectangular and box tables, horizontal and universal rotary tables, sine table, etc. Rotary tables for cattle, in addition to fastening, they provide the ability to rotate parts, due to which a rotary positioning movement is added to the longitudinal and transverse movements on the machine.

Fixing accessories

This group includes different types stands, prisms, all kinds of clamping bars, jacks, stubs, threaded rods, and fastening bolts with a set of nuts and washers, etc.

Fixing devices

With the help of which the location of the part is determined or the part is installed in the required position. These devices are used to set the reference surfaces of the workpieces relative to the machine spindle.

Tool holder accessories

These include eccentric chucks, adapter sleeves, reducer taper bushings, mandrels, boring bars, universal chucks, tool holders for fastening cutters when boring holes large diameters, special chucks for turning, special chucks for milling, etc.

The boring machine is used for processing workpieces in both single and batch production. Such equipment belongs to the universal class. It is possible to process products with high quality, including without transferring the workpieces to any other specialized machines.

Main purpose

Machines of this type are used primarily, of course, for boring holes of different diameters in blanks. But if necessary, they can also be used for:

• turning the outer surfaces of cylindrical parts;
• processing of the ends of the workpieces;
• countersinking and reaming holes;
• threading;
• milling.

Types of boring machines

Equipment of this type can be classified according to several criteria. According to the scope of application, such machines can be:

• universal turning and boring;
• specialized.

The machines of the second group, in turn, are subdivided into the following types:

• horizontal boring;
• jig boring;
• diamond boring.

Recently, CNC boring machines have become very widespread at enterprises.

What working tools are used

Operations on equipment such as a boring machine can thus be done in a variety of ways. When processing parts on these units, cutting tools are used such as:

• drill;
• cutter;
• cutter;
• countersink;
• tap, etc.

When choosing this type of equipment of any type, first of all, they pay attention to the diameter of the spindle.

What can be a jig boring machine

Equipment of this type is designed primarily for the most accurate processing of workpieces. Jig boring machines can be:

• single-column;
• two-column.

The design of such machines includes:

• bed;
• rack;
• table with skids;
• boring head.

Also, a traverse is included in the design of such equipment.

Features of work on a coordinate boring machine

When using equipment of this type, the workpiece to be processed is preliminarily fixed on the working table. Next, the required cutting tool is installed in the spindle. Then the work is done in the following order:

• depending on the height of the workpiece, adjust the traverse and boring head;
• set the spindle to the specified coordinates.

The last operation on equipment such as a jig boring machine, depending on its type, can be performed in different ways. On a single column model, the spindle is properly positioned by moving the work table in two perpendicular directions. On two-rack equipment:

• the table is moved in the longitudinal direction;
• the boring head is moved laterally along the traverse.

Range of jig boring machines

Many manufacturers produce such equipment today. But most often, enterprises use coordinate boring machines:

• 2E450. This single column model has a table dimensions of 630 x 1120 mm and is equipped with an optical measurement system, supplemented by a screen readout. Also, this boring machine has an automatic slide stop function. Another convenience-enhancing addition to this model is the preset device.
• 2D450. This model also has a table size of 630 x 1120. The optical device included in its design can count both integer and fractional parts of coordinates.

Of course, other coordinate boring machines can also be used in enterprises. Models 2A450, 2L450AF11-01, for example, are also in great demand today.

Horizontal boring machines

Such equipment is also used quite often in enterprises and workshops. Its main distinctive feature is that the spindle is horizontal in it. The main movement of the latter is rotational-translational relative to the axis. In this case, during turning, both the supply of the workpiece and the movement of the working tool itself can be carried out.

Moving the headstock on equipment such as a horizontal boring machine is an additional movement.

What models can be used

Equipment of this type can be supplied to the market today, both conventional universal with a spindle with a diameter of 110-130 mm, and heavy. The latter type machines are usually additionally equipped with a slider and a movable column.

Manufacturers also produce many models of such equipment. For example, aggregates of the VFC and F.O.R.T lines are very popular among consumers.

The horizontal boring machine VFC can be designed for processing workpieces weighing up to 10 tons. Such machines are used mainly for boring parts made of cast iron and steel. These models are built on a modular basis and have a turntable.

The F.O.R.T series machines are also available on the market in a very wide range. They can have a classic design with a cruciform table or with a movable column. Table sizes of F.O.R.T horizontal boring machines range from 1250 x 1400 mm to 4000 x 4000 mm. In this case, the spindle diameter can be equal to 100-260 mm.

Diamond boring machines

Equipment of this type is intended mainly for fine finishing of workpieces. The tools in such machines, as can already be judged by their name, use either diamond or carbide. A boring machine of this type can be used for processing workpieces made of steel and cast iron, as well as from alloys of non-ferrous metals, ebonite, textolite, rubber, etc. In some cases, diamond boring can even replace grinding.

Cutting on such equipment is carried out at a significant speed and at the same time a small depth of material removal. By the location of the spindle, diamond boring machines can be horizontal or vertical.

The lineup

This type of equipment on the market is not as widespread as horizontal and coordinate boring machines. However, there are also quite a few brands of such units produced today. One of the most popular models of such equipment is the 2A78. This boring machine has very good technical characteristics. The dimensions of the table for this model are 500 x 1000. Using this equipment, you can make holes in workpieces with a diameter of 27-200 mm.

Lathes and boring machines

The main feature of this type of equipment is a very high spindle rotation speed. The boring lathe can be used to process both flat parts and cylindrical.

When working on such equipment, the workpiece is mounted on the table. In this case, the spindle performs a rotational-translational movement.

Modern industry also produces large-sized lathes and boring machines. The turning diameter of such equipment can be equal to 4 m. At the same time, the machine is allowed to process parts up to 32 m long. The most popular model of a turning-boring machine at the moment is 2A656RF11.

CNC equipment

CNC can be supplemented with both diamond and horizontal, turning and coordinate boring machines. Modern electronics, of course, significantly increases the convenience of using this equipment. The work of a CNC machine is not controlled by a turner manually, but through a computer. This allows for the highest drilling or cutting accuracy and maximum productivity.

Boring machines with CNC can be used for both roughing and finishing workpieces. They cost, of course, much more expensive than conventional models. Only turners who have undergone a retraining program can work on such machines.

Boring machines are a class of industrial metalworking equipment, on which operations are performed to drill and increase the diameter of through or blind holes, as well as thread cutting. These units are used for the processing of large-sized parts in a batch or one-off production.

This article introduces boring machines. We will consider their functional purpose, principle of operation and design features, as well as provide an overview of popular equipment models.

See also: what is it and how does it work?

1 Boring machine - possibilities, principle of operation

A group of boring units has a characteristic feature, their spindle, fixed in a horizontal (less often vertical) plane, makes an axial movement towards the workpiece. A working tool is fixed in the spindle seat, the type of which directly depends on functionality machine tool.

Modern boring machines are capable of performing the following technical operations:

• boring;
• countersinking;
• drilling;
• threading (internal and external);
• turning;
• milling (face and cylindrical);
• trimming the ends.

In fact, these machines are universal multifunctional equipment that can fully replace several metalworking installations.

A key parameter of any boring machine is the diameter of the spindle that carries the main tool. Depending on it, all units are classified into three groups: small (diameter 50-125 mm), medium (100-200 mm) and heavy (200-320 mm).

The spindle rotation is the main movement of the machine, while the feed movement, depending on design features equipment, can be reported either to the workpiece or cutting tool... The movement of the tool can be axial, radial or vertical, the movement of parts occurs due to the movement of the working table.

1.1 Design features

Depending on the design features, all boring units are divided into two groups: horizontal and vertical. The most common is a vertical boring machine, consider its typical design using the example of the popular 2E78P model.

• work spindles (1, 2, 3, 4, 5);
• control unit (6);
• electrical equipment panel (7);
• bearing column (8);
• work table (9);
• base (10);
• reading device (11);
• pair box of speeds and feeds (12);
• spindle head (13);
• workplace lighting (14);
• electrical equipment control panel (15).

A characteristic feature of the 2E78P finishing boring machine is the ability to install interchangeable spindles different diameters- 120, 78 and 48 mm, which increases the diameter of the bore holes. The cutters are fixed on the spindle by means of a clamping vent; a center finder is mounted in the hole located at the end of the spindle cutter head (in the 2E78P, an indicator type center finder is used). The center finder is an auxiliary tool in the form of an overhead template that allows you to accurately align the axes of the cutter and the bore hole.

The 2E78P working table consists of two blocks: the lower slide, moving transversely along the bed guides, and the table panel itself, moving in the longitudinal direction along the slide. On the front wall of the panel there is a ruler for precise positioning of the table. Its installation and movement are carried out manually by means of handwheels.

The headstock is one of the key components of the unit; it consists of an engine, a spindle, and a V-belt transmission connecting them. An oil bath is formed inside the headstock body by the body ribs, in which the rotating shafts are located.

A gear box is installed on the 2E78P boring machine and other models of medium and heavy units. In this model, it gives 12 speeds of rotation of a spindle and 4 speeds of working feeds of a spindle head. An overrunning clutch is also provided for rapid movement of the headstock directly from the drive.

All boring machines are equipped with overload-resistant asynchronous motors, collector motors can be found only in low-quality Chinese equipment. In the 2E78P model, 3 engines are installed, one of which is responsible for moving the spindle head, the second for its accelerated movement, and the third for moving the desktop.

2 Types of equipment

All variety of boring machines, depending on functional purpose and design features, classified into the following types:

• drilling and boring;
• boring and surfacing (mobile and stationary);
• milling and boring;
• turning and boring.

Boring and boring machines were previously the most common group of equipment that could be found in any metalworking workshop, but now most of the drilling operations are performed on milling equipment, which is why the use of such units has decreased. Depending on the area of ​​application, they are divided into universal and specialized (for the mass production of a specific part).

A boring lathe is generally used to machine planes and holes inside hull structures. Such equipment is often called coordinate equipment, since it allows you to achieve high accuracy in the location of holes relative to the plane. base surface... In addition to the standard functionality, these units can perform marking operations.

The mobile boring and surfacing machine differs significantly from the considered mechanisms. It is a portable equipment used for repair and refurbishment cylindrical holes on large equipment. Such units can work in any place and spatial position, which makes them indispensable in the field of automotive, ship and aircraft construction.

Separately, we highlight diamond boring machines, characteristic feature which is the use of carbide cutters with diamond spraying, allowing for the processing of workpieces from hardened steels. Such units are often used for high-precision boring of automotive parts - connecting rods, bushings, cylinders, etc.

2.1 Overview of the machine 2A6622F4 (video)

2.2 Popular models of boring machines

One of the most common vertical boring units is the 2E78P model, which the Maikop Machine-Tool Plant has been producing from 1982 to the present day. This equipment is also capable of performing milling operations on parts made of steel, cast iron and non-ferrous metals.

Consider the technical characteristics of 2E78P:

• diameter of bored holes - from 29 to 200 mm;
• drilling diameter - up to 15 mm;
• maximum dimensions of the processed parts: 75 * 50 * 45 cm, weight - up to 200 kg;
• desktop dimensions - 100 * 50 cm;
• drive power - 2200 W;
• spindle speed - 26-120 min.

Among the horizontal equipment, we single out the 2A622F4 machine, the manufacturer is the Leningrad Machine-Tool Plant named after V.I. Sverdlov. This unit is equipped with CNC - numerical control, which significantly expands its functionality.

The CNC allows you to program the automatic movement of the working mechanism along four axes - X, Y, Z, W. The possibility of manual control from the remote control is also provided. The machine uses a Russian-made CNC system - CNC 2C42, corresponding to the F4 automation class. The unit is equipped with an electronic display, which displays data on the operating mode of the machine.

Technical characteristics of model 2A622F4:

• diameter of bored holes - from 15 to 250 mm;
• drilling diameter - up to 50 mm;
• maximum dimensions of the processed parts: 100 * 100 * 125 cm, weight - up to 5000 kg;
• dimensions of the desktop - 125 * 125 cm;
• drive power - 20,000 W;
• spindle speed - 4-1250 min.

This is a large-sized equipment for industrial operation, focused on use in a single and batch production. The dimensions of the machine are 398 * 634 * 398 cm, weight - 20 tons. Among the operational advantages of this unit, we highlight the presence of high-speed hydraulic clamps that automatically fix the workpiece, the device of the spindle assembly on precision bearings and the use of telescopic guides.