CN113601265B - A method for estimating the energy consumption ratio of the front and rear rake faces of the tool in machining - Google Patents

Abstract

The invention discloses a method for estimating the energy consumption ratio of the front and rear rake faces of a tool in machining. First, the working conditions to be analyzed are set, and several cutting tests are constructed according to the working conditions to obtain an energy consumption data array; The energy consumption difference array is used to calculate the energy consumption of the flank face under the working conditions by fitting the relationship between the energy consumption difference and the cutting parameters. Finally, the energy consumption ratio of the flank face and the energy consumption ratio of the rake face are calculated. The significant effect of the invention is that the ratio of the energy consumption of the rake face of the tool to the energy consumption of the flank face can be quantified, so as to directly reflect the energy loss of the front and flank faces of the tool during the cutting process. It provides important numerical basis for wear separation, tool optimization and optimization design, tool wear state analysis and tool change decision-making.

Description

A method for estimating the energy consumption ratio of the front and rear rake faces of the tool in machining

technical field

The invention relates to the energy consumption of machining process or the energy consumption of machine tools, in particular to a method for evaluating the energy consumption ratio of front and rear rake faces of a tool.

Background technique

The amount of machining is large and wide, and it is accompanied by huge energy consumption. Analyzing and determining the proportion of energy consumption in the machining process (which is a problem with the separation of energy consumption) is of great significance for energy-saving design, decision-making and optimization.

The separation of energy consumption in the machining process can be carried out along the two dimensions of time and space. In the spatial dimension, many studies have analyzed the physical composition of machining systems and machine tools, such as cooling Tool change mechanism, chip removal mechanism, etc., determine the energy consumption of each component through measurement and modeling; in the time dimension, there are periods of standby, startup, dry run, feed, cutting, etc. for the processing system or machine tool The energy consumption of the machine tool has been studied, and there are also studies on the separation of energy consumption for the energy transfer path (chronological order). Spindle energy consumption, etc. These studies are very valuable, and many research results have been applied in practice.

However, the current general treatment method for the energy entering the cutting area is as a whole without further separation. The common practice is to use the output energy of the machine tool spindle as the input energy of the cutting area. The energy problem in the cutting area mainly involves the energy consumption of the tool in the process of removing the machining allowance of the workpiece. The separation of energy consumption in the cutting area has theoretical significance for further clarifying the composition of energy consumption on the one hand, and on the other hand, the optimization and optimization of the tool design, tool wear and tear. Status analysis and tool change decisions, as well as the optimization of cutting amount, have practical significance.

SUMMARY OF THE INVENTION

Aiming at the problem of energy consumption separation in the cutting area, the present invention provides a method for separating the energy consumption in the cutting area into the energy consumption of the rake face and the flank face of the tool, so as to determine the energy consumption ratio of the front and rear rake faces of the tool; the method In particular, it can support tool optimization and optimal design, tool wear status analysis and tool change decision-making. The main technical solutions adopted are as follows:

A method for estimating the energy consumption ratio of the front and rear rake faces of the tool in machining, the key lies in the following steps:

Step 1. Set the working conditions to be analyzed (v _cg , a _pg , f _g ), where v _cg is the cutting speed, a _pg is the back cutting amount, and f _g is the feed amount;

Step 2: Construct several cutting tests in sequence according to the working conditions. The conditions for the cutting test are (v _cg , a _pg , f _i ), where:

i=1,2,3...,n;

f _i =f ₁ , f ₂ , . . . , f _n ;

n≥6;

f _i =f ₁ *i;

f _g ∈ f _i ;

Step 3: Carry out the cutting test according to the above settings, and record the corresponding energy consumption data array E;

E=(E ₁ , E ₂ , . . . , _En );

The energy consumption data corresponding to the analysis conditions (v _cg , a _pg , f _g ) are E _g , E _g ∈ E _i ;

Step 4. Construct the energy consumption difference array ΔE;

ΔE=(ΔE ₂ , ΔE ₃ ,...,ΔE _n )=((E ₂ -E ₁ ),(E ₃ -E ₂ ),...,(E _n -E _n-1 ));

Step 5. Fit the relationship between ΔE _i and f _i ;

ΔE _i =G(fi ₎ ;

Step 6, calculating the energy consumption E _b of the flank face under the described working conditions;

E _b =E ₁ -ΔE ₁ =E ₁ -G(f ₁ );

Step 7. Calculate, under the working conditions, the energy consumption of the flank face is c%, and the energy consumption of the rake face is 1-c%;

c%=E _b /E _g ×100%=(E ₁ −G(f ₁ ))/E _g ×100%.

Detailed ways

The present invention will be further described below in conjunction with the examples.

Example 1:

A method for estimating the energy consumption ratio of the front and rear rake faces of the tool in machining, which is carried out according to the following steps:

Step 1. Set the working conditions to be analyzed (v _cg , a _pg , f _g ), where v _cg is the cutting speed, a _pg is the back cutting amount, and f _g is the feed amount;

Step 2: Construct several cutting tests in sequence according to the working conditions. The conditions for the cutting test are (v _cg , a _pg , f _i ), where:

i=1,2,3...,n;

f _i =f ₁ , f ₂ , . . . , f _n ;

n≥6;

f _i =f ₁ *i;

f _g ∈ f _i ;

Step 3: Carry out the cutting test according to the above settings, and record the corresponding energy consumption data array E;

E=(E ₁ , E ₂ , . . . , _En );

The energy consumption data corresponding to the analysis conditions (v _cg , a _pg , f _g ) are E _g , E _g ∈ E _i ;

Step 4. Construct the energy consumption difference array ΔE;

ΔE=(ΔE ₂ , ΔE ₃ ,...,ΔE _n )=((E ₂ -E ₁ ),(E ₃ -E ₂ ),...,(E _n -E _n-1 ));

Step 5. Fit the relationship between ΔE _i and f _i ;

ΔE _i =G(fi ₎ ;

Step 6, calculating the energy consumption E _b of the flank face under the described working conditions;

E _b =E ₁ -ΔE ₁ =E ₁ -G(f ₁ );

Step 7. Calculate, under the working conditions, the energy consumption of the flank face is c%, and the energy consumption of the rake face is 1-c%;

c%=E _b /E _g ×100%=(E ₁ −G(f ₁ ))/E _g ×100%.

Example 2:

A method for estimating the energy consumption ratio of the front and rear rake faces of the tool in machining, which is carried out according to the following steps:

Step 1. Set the working conditions to be analyzed (v _cg , a _pg , f _g ), where v _cg is the cutting speed, a _pg is the back cutting amount, and f _g is the feed amount;

Step 2: Construct several cutting tests in sequence according to the working conditions. The conditions for the cutting test are (v _cg , a _pg , f _i ), where:

i=1,2,3...,n;

f _i =f ₁ , f ₂ , . . . , f _n ;

n≥6;

f _i =f ₁ *i;

f _g ∈ f _i ;

f _n is greater than the maximum feed used by the tool;

The feed sequence f _i is assigned and constructed under the conditions of considering the blunt circle radius of the cutting edge of the tool, the presence or absence of negative chamfering, and the range of the feed;

Step 3: Take the main cutting force F _i as the energy consumption data, and record the corresponding main cutting force array F;

F=(F ₁ , F ₂ , . . . , F _n );

The main cutting force corresponding to the analysis condition (v _cg , a _pg , f _g ) is F _g , F _g ∈ F _i ;

Step 4. Build the main cutting force difference array ΔF;

ΔF=(ΔF ₂ , ΔF ₃ ,...,ΔF _n )=((F ₂ -F ₁ ),(F ₃ -F ₂ ),...,(F _n -F _n-1 ));

Step 5. _Fit the relationship between _ΔFi and fi;

ΔF _i =G(fi ₎ = _Kfi ^b , where:

K is the coefficient of fitting, and b is the index of fitting, which is obtained according to the measured main cutting force and the corresponding feed;

Step 6: Calculate the main cutting force F _b of the flank face under the working conditions;

F _b =F ₁ -ΔF ₁ =F ₁ -G(f ₁ )=F ₁ -Kf ₁ ^b

Step 7. Calculate, under the working conditions, the energy consumption of the flank face is c%, and the energy consumption of the rake face is 1-c%;

c%=(F ₁ -Kf ₁ ^b )/F _g ×100%;

The main cutting force F _i can be obtained by measurement or calculated according to the following formula:

in:

C _Fc is a coefficient related to processing materials and processing conditions, obtained through cutting experiments or obtained from tool manuals;

K _Fc is the correction coefficient, obtained through cutting experiments or by checking the tool manual;

X _Fc is the index of a _pg , obtained by cutting experiments or by checking the tool manual;

Y _Fc is the index of f _i , obtained by cutting experiments or by checking the tool manual;

n _Fc is the index of v _cg , obtained by cutting experiments or by checking the tool manual.

Similarly, in step 3, the energy consumed by the machine tool spindle J, the power consumed by the machine tool spindle W, the current A consumed by the machine tool spindle, or other data that has a linear relationship with the main cutting force can be equal to the energy consumption data. , proceed to the next steps.

Example 3:

Based on the method of Embodiment 2, the experiential formula of the outer circle longitudinal vehicle index is used as an example to illustrate. According to "Machining Technology Manual", use carbide turning tool to longitudinally turn the outer circle of 45 steel, take C _Fc = 2650, K _Fc = 1.0, X _Fc = 1.0, Y _Fc = 0.75, n _Fc = -0.15;

It is necessary to analyze the energy consumption ratio of the front and rear rake surfaces of the tool when the cutting speed is v _cg = 60m/min, a _pg = 2mm, and f _g = 0.4mm/r.

Build feed sequence f _i =0.1, 0.2, 0.3, 0.4, 0.5, 0.6;

计算得到的主切削力数组F为：According to the formula

The calculated main cutting force array F is:

F=(F ₁ , F ₂ , ..., F ₆ )=(509.98, 857.68, 1162.50, 1442.44, 1705.22, 1955.09);

The main cutting force difference array ΔF constructed according to the main cutting force array F is:

ΔF=(ΔF ₂ , ΔF ₃ , . . . , ΔF ₆ )=(347.70, 304.82, 279.94, 262.78, 249.87);

The formula constructed according to the formula ΔF _i =G(fi ₎ = _Kfi ^b is:

ΔF _i =G(fi ₎ = _Kfi ^b =5.363· ^{fi -0.300} _;

Under the above working conditions, the energy consumption ratio c% of the flank face is:

c%=(F ₁ -Kf ₁ ^b )/F _g ×100%=(509.98-5.363· ^0.1-0.300 )/1442.44×100%=5.81%;

The energy consumption ratio of the rake face is 1-c%=94.19%.

Theoretical basis: According to the cutting deformation theory, the metal material undergoes shear deformation under the extrusion action of the tool, and is divided into the first deformation zone, the second deformation zone and the third deformation zone according to the different parts of the deformation. The first deformation zone is the shear-slip deformation of the material under the extrusion of the rake face, which is the area where chips are generated; the second deformation zone is the severe friction and further deformation of the chips under the pushing action of the rake face. The deformation causes the chips to separate from the base material; the third deformation zone occurs between the flank and the machined surface, and is the deformation of the machined surface under the extrusion and friction of the flank. From the perspective of the origin of the force of material deformation, the first deformation zone and the second deformation zone can be classified into one category, which are caused by the rake face, and the third deformation zone is classified into another category, which is caused by the flank face. cause. From the point of view of the usefulness of the work, the function of the work of the rake face is to make the material undergo shear slip to form chips, and further separate the chips from the material matrix. This part of the work is useful and unavoidable; The work done by the blade face is to squeeze and rub the machined surface, causing the machined surface to produce elastoplastic deformation, work hardening and friction heat. This part of the work is useless, and it is hoped that it is as small as possible or even zero. Based on this, it is reasonable to divide the energy consumption of the cutting area into the energy consumption of the rake face and the flank face.

The energy consumption of the flank is mainly used to resist the elastic-plastic deformation of the workpiece caused by the flank and the friction between the flank and the machined surface, its size and the size of the contact surface, the geometry of the contact surface, and the friction between the tool and the material. Coefficient, tool clearance angle, flank wear and damage status, tool material and tool material properties, etc. Among the three elements of cutting amount, the back engagement amount a _p directly affects the contact area and contact state between the flank and the workpiece; the cutting speed _vc hardly affects the contact area between the flank and the workpiece, but different cutting speeds will cause cutting Changes in temperature, boundary stress distribution, etc., will affect the contact state between the flank and the workpiece; for most machining situations, the feed f will not affect the contact area between the flank and the workpiece, and the impact on the friction state is also Very small (for less machining situations, such as grooving, cutting, etc. on a lathe, the change in feed will significantly change the actual clearance angle of the tool, which will lead to changes in the contact state between the tool flank and the workpiece, so this method is suitable for Larger errors are expected in such cases). Therefore, it can be considered that changing the feed rate does not affect the energy consumption of the flank face given the cutting speed and the amount of back engagement. Considering that when constructing the feed sequence, there are theoretically countless possible sequences, and the energy consumption of the front and rear rake faces calculated by different sequences is different; at the same time, since the empirical formula of the cutting force index is obtained through cutting experiments, The factors and levels used in the experiment have a significant impact on the coefficients and exponents in the formula. When there is a big difference between the feed sequence in this method and the feed level selected in the cutting experiment, it may lead to the presumed front and rear cutters. The surface energy consumption is quite different from the real situation. For this reason, based on the practical principle, the construction of the feed sequence needs to consider factors such as the radius of the blunt circle of the tool cutting edge, the presence or absence of negative chamfers, the rationality of the feed range, etc. The following is a feed sequence for reference Construction method: f ₁ is the minimum feed, but it cannot be too small, and it should be able to cut normally. According to the "Metal Cutting Handbook", when the radius of the blunt circle of the cutting edge is r _n , f ₁ ≥ 3r _n ; When it is the negative chamfer of b _γ1 , if it is processing low carbon steel, stainless steel and gray cast iron, etc., it should make f ₁ ≥ 2b _γ1 , if it is processing medium carbon steel, alloy structural steel, etc., it should make f ₁ =1.25～3.3 b _γ1 , if the cutting impact load is large, f ₁ =0.5～0.7b _γ1 ; f _n is the maximum feed, which should be greater than the maximum feed used by the tool, which can be determined according to the tool material, workpiece material, v The known conditions such as _cg and a _pg can be obtained by checking the cutting quantity manual. The checked value is often a range, try to take a larger value, and f _n can also be directly given by experienced workers.

Beneficial effects: By adopting the technical scheme of the present invention, the ratio of the energy consumption of the rake face of the tool and the energy consumption of the flank face can be quantified, so as to directly reflect the energy loss of the front and flank faces of the tool in the cutting process. The optimization and optimization design, tool wear state analysis and tool change decision-making provide important numerical basis.

Finally, it should be noted that the above description is only a preferred embodiment of the present invention, and those of ordinary skill in the art can make a variety of similar It is indicated that such transformations fall within the protection scope of the present invention.

Claims (3)

1. a method for estimating the energy consumption ratio of the front and rear rake faces of the tool in machining is characterized in that carrying out by the following steps: Step 1. Set the working conditions to be analyzed (v _cg , a _pg , f _g ), where v _cg is the cutting speed, a _pg is the back cutting amount, and f _g is the feed amount; Step 2: Construct several cutting tests in sequence according to the working conditions. The conditions for the cutting test are (v _cg , a _pg , f _i ), where: i=1,2,3...,n; f _i =f ₁ , f ₂ , . . . , f _n ; n≥6; f _i =f ₁ *i; f _g ∈ f _i ; Step 3: Carry out the cutting test according to the above settings, and record the corresponding energy consumption data array E; E=(E ₁ , E ₂ , . . . , _En ); The energy consumption data corresponding to the analysis conditions (v _cg , a _pg , f _g ) are E _g , E _g ∈ E _i ; Step 4. Construct the energy consumption difference array ΔE; ΔE=(ΔE ₂ , ΔE ₃ ,...,ΔE _n )=((E ₂ -E ₁ ),(E ₃ -E ₂ ),...,(E _n -E _n-1 )); Step 5. Fit the relationship between ΔE _i and f _i ; ΔE _i =G(fi ₎ = _Kfi ^b , where: K is the coefficient of fitting, and b is the index of fitting, which is obtained according to the measured energy consumption data and the corresponding feed; Step 6, calculating the energy consumption E _b of the flank face under the described working conditions; E _b =E ₁ -ΔE ₁ =E ₁ -G(f ₁ ); Step 7. Calculate, under the working conditions, the energy consumption of the flank face is c%, and the energy consumption of the rake face is 1-c%; c%=E _b /E _g ×100%=(E ₁ -G(f ₁ ))/E _g ×100%; In the third step, the main cutting force F _i is equal to the energy consumption data, so that the following steps are performed based on the main cutting force F _i ; the main cutting force F _i may be obtained by trial cutting tests , or calculated by the following formula;

in: C _Fc is a coefficient related to processing materials and processing conditions, obtained through cutting experiments or obtained from tool manuals; X _Fc is the correction coefficient, obtained through cutting experiments or by checking the tool manual; X _Fc is the index of apg, obtained by cutting experiments or by checking the tool manual; Y _Fc is the index of f _i , obtained by cutting experiments or by checking the tool manual; n _Fc is the index of v _cg , obtained by cutting experiments or by checking the tool manual. 2. The method for estimating the energy consumption ratio of the front and rear rake faces of the tool in machining according to claim 1, wherein in the step 3, the main cutting force, or the energy consumed by the machine tool spindle, or The power consumed by the machine tool spindle or the current consumed by the machine tool spindle is equal to the energy consumption data, and the subsequent steps are performed. 3. A method for estimating the energy consumption ratio of the front and rear rake faces of a tool in machining according to claim 1 or 2, characterized in that: the feed sequence f _i takes into account the blunt circle radius of the tool cutting edge and the Assignment construction is performed without negative chamfering and feed range.