The advantages of CNC slant bed lathe machine in use
With the digitalization of machining in our country and the development trend of full automation, more and more CNC
lathes are introduced into this industry and serve the economic construction of our country.CNC slant bed lathe is a
relatively comprehensive precision CNC lathe, not only has high precision, but also is relatively durable, not only has a
good appearance, but also has good practicability. advantages. Therefore, this type of equipment is widely used in the
fields of aviation, electronics, clocks and watches in our country, especially for high-precision, multi-batch, and complex-
shaped parts. We must use this type of machine tool for processing to ensure that the manufactured parts The required
accuracy can be achieved. This paper mainly analyzes the advantages of CNC slant bed lathes machine by comparing
slant bed CNC machine tools and flat bed CNC machine tools.
1. Introduction to the basic situation of CNC lathe with slant bed
1.1 The overall situation of the slant bed
In the actual cutting process, the slant bed CNC lathe has the function of optional power tool and 8-station turret tool holder, so it can play an important role in
the processing of different products, especially in the processing of various products, small and medium batches It is relatively applicable in the processing of
products; especially in complex and high-precision parts, it obviously has advantages that other products do not have.
1.2 Preparations before commissioning of CNC lathe with slant bed
Before use, the slant bed CNC lathe must first pass the geometric accuracy inspection, and then clean the whole machine. Specifically, it is necessary to use
cotton cloth or silk cloth containing cleaning agent for cleaning. Cotton yarn or gauze cloth should not be used at this stage to avoid machine jamming. Wash off
the anti-rust oil or anti-rust paint applied to the machined surface, and clean the dust on the outer surface at the same time. At the same time, apply the
lubricating oil specified by the manufacturer on each sliding surface and working surface. At the same time, it is also necessary to carefully check whether all
parts of the CNC lathe with inclined bed have been filled with oil according to relevant requirements, and whether the coolant in the cooling box is sufficient.
Whether the oil in the hydraulic station of the machine tool and the lubricating device in the automatic room can reach the position specified by the oil level
indicator. At the same time, check whether the switches and components in the electrical control box are normal, and whether the plug-in integrated circuit
boards are operating normally. After power on, we also need to start the centralized lubrication device to ensure that there is enough lubricating oil on the
lubricating parts and lubricating oil roads, so as to do a series of preparations for the machine tool before use.
1.3 Installation of slant bed CNC lathe
The slant bed CNC lathe is placed on the foundation and must be leveled in a free state and locked by anchor bolts. As far as ordinary machine tools are
concerned, the level gauge reading will not be higher than 0.04/1000mm, and if it is a high-precision CNC machine tool, the level gauge will not be higher than
0.02/1000mm. When measuring the installation accuracy, we often have to do it at a constant temperature, and the measurement tools need to be used after a
period of time to set the temperature. When installing the CNC lathe with inclined bed, it is necessary to reduce the installation method of forced deformation
caused by the CNC machine tool as much as possible. When installing the inclined bed CNC lathe, some parts of the machine tool cannot be removed casually.
If some parts are removed, it is likely to cause the internal stress of the CNC lathe to be redistributed, thereby affecting the accuracy of the machine tool.
2.Comparison of inclined bed and flat bed CNC machine tools
In China, there are two common types of CNC machine tools: flat bed CNC lathes, also known as economical CNC lathes, or simple CNC machine tools, and
the other is slant bed CNC lathes, also called popular CNC lathes and Full function CNC lathe. According to our analysis of the two kinds of CNC machine tools,
it is not difficult to find that the CNC lathe with slant bed is compared with the CNC lathe with flat bed. From the perspective of use, although both flat bed CNC
lathes and slant bed CNC lathes can be used for CNC turning, the specifications of the parts that can be processed are different. CNC machine tools mainly
appeared for the realization of modern mass production, and its biggest feature is automation, which reduces a lot of repetitive manual labor. Flat bed CNC
lathes are all formed by simple CNC transformation of ordinary lathes, so they are often difficult to automate. The slant bed CNC lathes are different. They are
mainly designed based on the basic principles of CNC machining and have strong pertinence. In terms of, there are obvious improvements. These advantages
are given at the time of design and cannot be obtained through subsequent improvements.
2.1 Machine tool layout comparison
From the perspective of the layout of the two CNC lathes, the biggest feature of the flat bed CNC lathe is that the plane where the two guide rails are located is parallel to the ground plane, while the inclined bed CNC lathe is different, and the plane where the two guide rails are located is parallel to the ground plane. The planes are intersected, and there will also be a slope, and the slope angle can be 30°, 45°, 60°, 75°, etc. According to the side conditions of the second type of machine tool, we can find that the bed of the flat bed CNC lathe is square, and the bed of the inclined bed CNC lathe is a right triangle. From this point of view, we can obviously find that in the case of the same guide rail width, the X-direction carriage of the inclined bed will be longer than that of the flat bed, which means that more tool positions can be arranged.
2.2 Comparison of cutting rigidity
From the perspective of cutting performance, the cross-sectional area of a CNC lathe with an inclined bed is often larger than that of a flat bed of the same
specification, which means that it has stronger bending and torsion resistance. The cutting tools of the CNC lathe with inclined bed are cut from the oblique top
of the workpiece. The cutting force can be kept in the same direction as the gravity of the workpiece, so the spindle can maintain a relatively stable movement
and it is difficult to cause cutting vibration. The lathe is different. The cutting force generated by the tool and the workpiece is often kept perpendicular to the
workpiece, which is more likely to cause vibration.
2.3 Comparison of machining accuracy of machine tools
For CNC lathes, the transmission screw is a high-precision ball screw, and there is a small transmission gap between the screw and the nut, but it does not
mean that there is no gap. However, as long as there is a gap, when the screw moves in one direction and then drives in the opposite direction, there will be a
backlash. If there is a backlash, it will definitely affect the repeatability of the positioning accuracy and eventually reduce the machining accuracy. The layout of
the inclined bed CNC lathe is different. It can directly affect the clearance of the ball screw in the X direction, and the gravity will directly affect the axial direction
of the screw, so as to ensure that the backlash during transmission is zero. However, the X-direction screw of the flat-bed CNC lathe is not affected by the X-
axis gravity, so it is difficult to directly eliminate the gap. This is enough to show that the CNC lathe with inclined bed has advantages over the traditional flat bed
machine tool in terms of machining accuracy.
2.4 Comparison of Chip Removal Capabilities
Considering the influence of gravity, it is difficult for the CNC lathe with inclined bed to produce winding tools, and it often has a certain advantage in chip
removal; it also cooperates with the center screw and guide rail to protect the sheet metal, so as to avoid the chips on the screw and guide rail. accumulation
phenomenon. Most CNC lathes with inclined bed will design an automatic chip removal. The main function is to automatically remove chips and increase the
working hours of workers. However, the flat bed is limited by the structure, and it is often difficult to add an automatic chip removal machine.
2.5 Comparison of automated production
For CNC machine tools. Whether it is to increase the number of knives or configure an automatic chip conveyor, the ultimate goal is to automate production. In
the future, there will be a phenomenon that one person guards multiple machine tools on CNC machine tools. The CNC lathe with inclined bed will add another
milling power head, automatic feeding machine tool or manipulator, and at the same time, it will automatically load the material, complete all the construction
processes of the workpiece in one clamping, automatically lower the material, and automatically remove chips, that is to say Developed into an efficient fully
automatic CNC machine tool that no one needs to manage. Therefore, the flat bed CNC lathe does not have structural advantages if it wants to realize
automation.
2.6 Manufacturing cost comparison
Although the inclined bed CNC lathe is more advanced than the flat bed CNC lathe in many respects, it has not received a good response in the market. The
main reason is that flat bed CNC lathes are often not expensive, and the production is fast, so they are favored by many low-to-medium consumer groups,
especially small factories and small workshops. Relatively speaking, CNC lathes with inclined beds are more difficult to manufacture, and the bed is also
heavier. The X-axis also needs to have a servo motor with a brake function. The biggest disadvantage is the high manufacturing cost. Therefore, according to
the actual situation of my country’s manufacturing industry, most enterprises only need to process low-end products, and do not have too high requirements for
the precision of machine tools. The price factor is mainly considered when purchasing machine tools.
3. Analysis of the advantages of CNC lathe with inclined bed in use
According to the above analysis, we conclude that the inclined bed CNC machine tool has the following advantages, which are worthy of our attention.
3.1 Capable of processing high-precision products
For the carriage drive screw of CNC machine tools, it is basically a high-precision ball screw, and there is often a certain gap between the screw and the nut, so
when the screw moves in one direction and then drives in the opposite direction, it will Backlash will occur and affect the final machining accuracy. The CNC
machine tool with inclined bed will directly act on the axial direction of the screw rod under the action of gravity, and it is often difficult to have backlash during
transmission. For example, we can find an ordinary nut and screw, turn the screw vertically upwards, and then return it in the opposite direction. We will find that
the nut is always pressing the screw from one side, so that there will be no backlash. If we let the nut It is difficult to produce such an effect when it is placed flat
with the screw.
3.2 The machine tool has good rigidity, and it is not easy to cause vibration during cutting.
The tool of the CNC machine tool with inclined bed is often located above the workpiece when cutting. The cutting force is consistent with the gravity formed by
the spindle workpiece, so the spindle operation will be relatively stable, and cutting vibration is difficult to occur. This is not the case with ordinary CNC lathes
. When they are working, the cutting tool and the workpiece generate an upward cutting force, which produces inconsistent gravity with the spindle workpiece,
so it is easy to generate vibration, make a large noise, and ultimately affect the machine tool. Rigidity and longevity.
3.3 Other advantages of inclined bed CNC machine tools
According to our previous analysis, we found that the inclined bed CNC lathe is mainly used in the multi-variety and small-to-medium batch processing of
various precision and complex rotary parts. At the same time, we can also choose a hydraulic chuck and tailstock to achieve automatic loading and unloading,
and the selected system and functional components can be clamped at one time to realize turning and milling functions. It can obtain certain advantages in the
processing of inner circle, outer circle, step, cone surface, spherical surface, groove, various threads and complex curved surface. At the same time, it can also
process various high-temperature alloys, titanium alloys, heat-resistant alloys, stainless steel, Various processing of casting and forging blanks of cast iron, cast
steel and other materials. For castings, tempering must be carried out first to eliminate internal stress. Linear guideways are used for the X and Z-axis
guideways. For the entire cutting process, straightness correction must be performed to ensure the accuracy of machine tool movement and maintain cutting
accuracy. The precision of the product.
Finally, the inclined bed CNC lathe also has good reliability, rigidity, precision, long life, fast processing speed, and can perform rough, fine and finish processing
on various difficult-to-process materials. The spindle of the CNC lathe with inclined bed has short drag and twist, and the speed is high. All these advantages
are extremely conducive to its cutting work.
Post time: Jan-14-2023