The screw-cutting lathe 16K20 belongs to the category of universal metal-cutting equipment, suitable for performing a number of operations. The machine was produced in the period from the early 70s to the mid-80s by Moscow. Currently, only used units are on the market, but due to its reliability, low price and ease of maintenance, it is still widely used today for training purposes, in repair shops, as well as in production and repair shops for single and small-scale production of parts.
Capabilities of the 16K20 machine
The design characteristics of the 16K20 lathe allow it to be effectively used for turning surfaces with a workpiece length of up to 2000 mm and a weight of up to 1300 kg of both cylindrical and conical shapes. It can also be used for cutting workpieces, preparing holes, preparing various types of threaded connections - metric, inch, modular and pitch.
The machine's capabilities allow you to produce threads with different pitches. Thus, it is possible to cut modular and pitch threads with a pitch of 0.5 to 56, inch threads with a pitch of 0.5 to 112 threads per inch, and metric threads with a pitch of 0.5 - 112 mm. The screw-cutting lathe has an accuracy class H, ensures a deviation from cylindricity of no more than 7 microns, conicity - no more than 20 microns per 300 mm, end surface - 16 microns per diameter of 300 mm.
Design features of the machine 16K20
Let us note the main features and advantages of the machine, thanks to which it is still one of the most reliable and popular solutions for equipping repair and production workshops:
- The box-shaped frame is placed on a massive, monolithic base, which ensures the rigidity of the entire structure.
- High precision movement of the caliper and movable tailstock thanks to reliable guides.
- Possibility of fixing the workpiece in the chuck or by clamping in the centers.
- Reliable fixation of the cutter thanks to the design of the holder.
- High-precision spindle bearings guarantee high-precision positioning and rotation and do not require adjustment during operation.
- High security thanks to a range of fencing and locking elements. Emergency caliper shutdown.
- The headstock mechanism allows for four rows of spindle rotation numbers.
- The output shaft of the headstock is rigidly connected to the feed box through the engagement of replaceable gears. This ensures precise movement of the caliper from the lead shaft or lead screw depending on the operation.
- High precision of operations due to the presence of a ruler with sights for effectively checking the longitudinal and transverse movement of the cutting tool.
You can study the main technical characteristics of the 16K20 machine in the table below:
| Technical characteristics of the machine 16K20 | Options |
| Machining diameter above the bed, mm | 400 |
| Machining diameter above the support, mm | 220 |
| Distance between centers | 1000 / 1500 |
| Accuracy class according to GOST 8-82 | N |
| Size of the inner cone in the spindle | Morse 6 M80* |
| Spindle end according to GOST 12593-72 | 6K |
| Diameter of through hole in spindle, mm | 55 |
| Maximum weight of the workpiece fixed in the chuck, kg | 300 |
| Maximum weight of the part fixed at the centers, kg | 1 300 |
| Number of spindle rotation stages, pcs. | 23 |
| Number of spindle reverse rotation frequency steps | 12 |
| Frequency limits for direct spindle rotation, min-1 | 12,5 — 2 000 |
| Spindle reverse rotation frequency limits, min-1 | 19 — 2 420 |
| Number of working feed stages - longitudinal | 42 |
| Number of working feed stages - transverse | 42 |
| Limits of working feeds - longitudinal, mm/rev | 0.7 — 4,16 |
| Limits of working feeds - transverse, mm/rev | 0,035-2,08 |
| Number of metric threads cut | 45 |
| Number of inch threads cut | 28 |
| Number of modular threads to be cut | 38 |
| Number of pitch threads cut | 37 |
| Number of threads to be cut - Archimedean spiral | 5 |
| Maximum torque, kNm | 2 |
| Maximum movement of the quill, mm | 200 |
| Transverse displacement of the housing, mm | ±15 |
| Largest cutter section, mm | 25 |
| Main drive motor power | 10 kW |
| Electric motor power for fast movement of the caliper, kW | 0.75 or 1.1 |
| Cooling pump power, kW | 0,12 |
| Overall dimensions of the machine (L x W x H), mm | 2,812 / 3,200 x 1,166 x 1,324 |
| Machine weight, kg | 3 035 |
The design of the machine ensures high operational safety, reliability, simplicity and ease of maintenance. All this, along with low cost, guarantees its demand on the Russian market.
Areas of use and modification of the 16K20 machine
You can download the passport of the 16K20 screw-cutting lathe for free in pdf format here: Passport 16K20
The screw-cutting lathe model 16K20 belongs to the category of universal equipment for processing metal parts. Its characteristics, of course, do not allow it to replace milling equipment, but make it possible to use it to perform a whole list of specialized operations. Such operations, in particular, include cutting threads of various types (metric, inch, modular, pitch), drilling, countersinking and other types of turning.
The capabilities of this screw-cutting lathe are such that it can be used to process workpieces from both hot-rolled and cold-rolled steel. Before the appearance of this machine, enterprises used the 1K62 equipment model, which is significantly inferior to it in all its characteristics. Thus, the advantages of the 16K20 screw-cutting lathe (compared to the previous model) include:
- operational safety;
- high reliability;
- the ability to process parts with high precision;
- simplicity and ease of maintenance;
- exceptional durability even with active use;
- high performance.
Read also: What is the difference between a tray and a box
Screw-cutting lathes 16K20 are used in enterprises that produce products individually or in small batches, as well as in tool shops, where such equipment can be used to perform both semi-finishing and finishing work.
Among the design features of this screw-cutting lathe, the following can be noted.
- The equipment frame is made in a box-shaped form and installed on a massive monolithic base, which gives high rigidity to the entire structure. Precision movement along the caliper frame and movable tailstock is ensured by reliable guides, which are heat-treated and ground.
- Depending on the type of processing and configuration, the workpieces can be fixed in the chuck or clamped in centers.
- The cutter holder device is designed to ensure reliable fixation of the tool.
- To install the spindle, high-precision (precision) rolling bearings are used, which are necessary for the accuracy of its location and rotation.
- The design of the 16K20 screw-cutting lathe provides a number of blocking and fencing technical elements that ensure safe work on it.
- To ensure processing accuracy, the machine is equipped with rulers with sights, which can be used to control the longitudinal as well as transverse movements of the tool.
- You can urgently turn off the support feed of a 16K20 machine using a special device installed on the apron of the machine.
The 16K20 tool holder on the machine support looks like this:
Machine tool holder 16K20
Due to the versatility, reliability, simplicity of design and maintenance of the 16K20 screw-cutting lathe, analogues of this equipment were produced at a number of domestic and foreign enterprises, where they were designated:
- MK6058 (6057, 6056) – Machine tool building in Moscow;
- 16V20P, 16V20 – Astrakhan Machine Tool Plant;
- ZHA-805 – Automatic machine tools plant in Zhitomir;
- 16B16 and modifications, Samat 400 – Srednevolzhsky Machine Tool Plant in Samara;
- GH-1840ZX (“Jet” – Switzerland), CU402 (“Vratsa” – Bulgaria), CD6140A (“Anhui Chizhou” – China), BJ1630G, CS6240, CS6240 (“Bochi” – China), CA6240B, CA6140A (“SMTCL” – China).
- KA-280 - in Kyiv.
- 16VT20P, 16VT20 - in Vitebsk.
Analogues of the machine
The 16K20 screw-cutting lathe replaced the 1K62 model, surpassing it in all quality indicators. After it was discontinued, domestic and foreign manufacturers produced numerous analogues of the 16K20 machine with various additions. These are MK6056, MK6057 and MK6058 (Red Proletary, Moscow), 16VT20 and 16VT20P (Vistan, Vitebsk), 16B16, 16B16P, 16B16V and 16B16A (SVZS, Samara) and many other models. Thanks to many analogues and high standardization of parts, there is no shortage of spare parts and equipment to ensure uninterrupted operation of the 16K20 machine.
Gearbox 16K20
Gearbox assembly for screw-cutting lathe 16K20. You can also purchase a friction clutch for this gearbox.
Gear boxes are the most common mechanisms for regulating speeds in the main movement drives of universal machine tools. The advantages of gearboxes are as follows: the ability to regulate over a wide range, the ability to transmit significant power, reliable operation, and a constant gear ratio. The disadvantages of such boxes include the impossibility of stepless control, low efficiency, and the difficulty of switching gears on the go. The design of the gearbox is closely related to the design of the spindle drive, and their calculation and design are carried out jointly. According to their design, gearboxes can be divided into three groups:
1) boxes that differ in their location in the machine (in layout); 2) boxes that differ in the method of switching speeds; 3) boxes that differ kinematically.
Speed boxes in their layout and location in the machine are determined mainly by the purpose of the machine and its standard size and, in turn, are divided into three groups:
1) built-in gearboxes; 2) gearboxes, made in the form of an independent unit; 3) attached gearboxes.
Built-in gearboxes . In this case, the gearbox is constructed directly in the spindle head housing near the spindle unit, connected to it by a system of gears and is generally called “spindle head”. This arrangement is used in most general-purpose machines of medium and large sizes due to its compactness, fewer body parts, reduction in the number of castings and parts for butt fitting, and ease of transmission of rotation to the spindle. It should, however, be taken into account that the built-in gearbox serves as a source of harmful vibrations and heat for the spindle assembly, which is unacceptable in precision machines. According to the overall layout, these boxes come with a normal ratio of overall and axial dimensions and with reduced axial or radial dimensions.
a) Spindle heads with a normal ratio between axial and radial overall dimensions are used in small and medium-sized horizontal machines. For this purpose, gears and shaft axles are combined.
b) Headstocks with reduced axial dimensions are most often made due to the development of radial overall dimensions. This arrangement is used for machines with cantilever moving masses (the spindle head moves perpendicular to the spindle axis) in order to eliminate vibrations, in particular for radial drilling and longitudinal milling machines. The vertical layout of the machine also requires a reduction in the axial dimensions of the headstock - to reduce the overall height and vibration.
c) Headstocks with reduced radial dimensions
Due to the development of axial ones, they are used in heavy horizontal lathes and some other groups. This arrangement makes it possible to reduce the transverse dimensions of the machine, and therefore the width of the workshop bay.
Gearboxes made as an independent unit. These boxes are located in a separate housing (gearbox) and are used in machines with the so-called split drive. They eliminate the disadvantages inherent in built-in boxes; they provide smoother spindle rotation and are most often used in precision machines. A divided drive of the main movement in the machine (for example, in a machine type 1A616 (see Fig. 72) is typical for modern high-speed machines. In this case, the spindle head and gearbox are connected by a belt drive; a device is provided for unloading the spindle from the belt tension force. The advantage of this separate drive is as follows: spindle rotation at high speeds is transmitted directly through an elastic belt drive without the participation of gears, which ensures smooth, vibration-free operation of the machine; friction losses in the main drive are reduced due to the reduction in the number of high-speed gears and shaft supports in the kinematic chain; mechanisms controls in the machine are convenient, fast; installation and unification of speed boxes are facilitated. The split drive is widely used in small and medium-sized high-speed and precision machine tools, as well as in machines where it is difficult to place the speed box near the working element. In heavy machines, the split drive loses its advantages and therefore is almost never used. Attached gearboxes . When modernizing outdated models of metal-cutting machines with a step control drive, in order to increase their productivity, speed boxes are used - gearboxes, most often executed in the form of unified attached individual drives. They are installed on the foundation near the machine (directly or on a column) or directly on the machine and connected to the spindle using a belt drive. Unified attached gearboxes are available in four sizes to transmit power at 2.8; 4.5; 7 and 10 ket. To reduce the time it takes to stop the machine, electrical braking is provided in the attached boxes, and the rotation of the spindle is changed by reversing the electric motor. The method of switching gearbox stages is mainly determined by the purpose of the machine and depends on the frequency of switching and the duration of working strokes. In our catalog you will find a wide selection of spare parts and accessories for machines.
The average screw-cutting lathe 16K20 is a successful modification of the legendary Soviet machine 1K62.
Appearing in Soviet-made machine parks half a century ago, it continues to work today in many enterprises, although sometimes there is a need to buy a 16K20 spindle head , or some other unit to replace a worn one. The gearbox or headstock (also called the spindle headstock) includes several important components that determine the operating algorithms of the machine:
- the presence of a friction clutch guarantees three options for turning on the spindle - forward and reverse directions of rotation, as well as stopping with braking;
- the gearbox mechanism allows you to select one of 24 spindle rotation speeds, forming the main movement of the machine;
- The spindle unit ensures spindle rotation in precision bearings, ensuring the specified precision of metalworking.
Thus, the repair of the 16K20 gearbox can be associated both with the loss of the former accuracy of processing parts, and directly with the malfunctions that have arisen. As a rule, it involves a large amount of work, including dismantling, troubleshooting and a number of other operations, the implementation of which should be entrusted to professionals. In addition, only original spare parts must be used during repairs. An alternative to such a repair (usually a major one) is to buy a 16K20 headstock assembly and replace the entire assembly. Our company's catalog offers a wide range of spare parts of original quality. From us, a client can easily buy ready-made assembled units, including such complex and important ones as a spindle head. But the main advantage of our 16K20 gearbox is that you can buy the assembled product from us at the minimum manufacturer price.
