Numerical control lathe is multiple and compound dictate circularly (G70 ~ G76)

Use code of this group of G, can machine the part with more complex form, the simply when process designing specifies finish machining course and amount of penetration of a cutting tool of rough machining back, the system can be calculated automatically a rough machining course and treatment frequency, process designing efficiency is accordingly taller.

1.Outside round rough machining is compound circulate (G71)

Statement form Re of   of D of Δ of G71   U

            W Ff Ss Tt of Δ of U W of Δ of G71   Pns Qnf U

Instruction function Excision club expects semifinished product is major mental allowance, cutting is along parallel Z axis direction undertakes, see a picture 1,

Graph 1 outside round rough machining circulates

A is circular start, a-A’-B is finish machining course.

The instruction explains Δ D expresses every time cutting deepness (radius is worth) , without sign;

        E represents the amount that retreat a knife (radius is worth) , without sign;

        Ns represents finish machining line the suitable serial number of the first block;

        Nf states finish machining course is the last the suitable serial number of block;

       Δ U shows the finish machining surplus of X direction, diametical value;

            Δ W shows the finish machining surplus of Z direction.

Process designing of use loop instruction, should decide the dot that change a knife, loop nods A, cutting above all only then dot A ‘ the coordinate position with cutting terminus B. To save the auxiliary working hours of numerical control machine tool, use G00 to A of abide circling point from the dot that change a knife instruction of fast fixed position, the X coordinate of A of abide circling point is located in besides semifinished product dimension, z coordinate value and cutting only then dot A ‘ Z coordinate value is same.

Next, according to outside the statement form that round rough machining circulates and treatment craft requirement draw up G71 dictates block, there is U of two addresses accord with in dictating circularly, before one expresses to bear amount of penetration of a cutting tool, hind a finish machining surplus that shows X way. There is magic figures drawn by Taoist priests to invoke or expel spirits and bring good or ill fortune of address of P, Q in block, criterion the finish machining surplus that U of address accord with shows X way, express to bear amount of penetration of a cutting tool conversely. Quantity of back penetration of a cutting tool does not have negative worth.

A ‘ the contour line that → B is workpiece, a → A ‘ → B is finish machining course, the cutting tool when rough machining nods W of regressive Δ U /2, Δ from A, namely surplus of finish machining of automatic put apart. Ordinal date Ns describes the line that cutting tool cutting machines to the block between Nf.

1 graph shows example 2 times, process designing of instruction of loop of rough machining of the circle outside applying.

Graph 2 outside round rough machining applies circularly

N010 G50 X150 Z100

N020 G00 X41 Z0

N030 G71 U2 R1

N040 G71 P50 Q120 U0.5 W0.2 F100 

N050 G01 X0 Z0

N060 G03 X11 W-5.5 R5.5

N070 G01 W-10

N080 X17 W-10

N090 W-15

N100 G02 X29 W-7.348 R7.5

N110 G01 W-12.652

N120 X41

N130 G70 P50 Q120 F30

2.  End panel rough machining is compound circulate (G72)

Statement form D Re of Δ of G72   W

    W Ff Ss Tt of Δ of U W of Δ of G72   Pns Qnf U

Instruction function Dividing cutting is outside undertaking along direction of parallel X axis, this instruction function and G71 are identical, see a picture 3.

The instruction explains The meaning of W of U of Δ D, E, Ns, Nf, Δ , Δ and G71 are identical.

Graph rough machining of 3 end panel circulates

Graph rough machining of 4 end panel applies circularly

Example 2 show 4 times like the graph, apply process designing of instruction of loop of end panel rough machining.    

N010 G50 X150 Z100

N020 G00 X41 Z1

N030 G72 W1 R1

N040 G72 P50 Q80 U0.1 W0.2 F100 

N050 G00 X41 Z-31

N060 G01 X20 Z-20

N070 Z-2

N080 X14 Z1

N090 G70 P50 Q80 F30

3.  Fixed appearance cutting is compound circulate (G73)

Statement form K Rd of Δ of I W of Δ of G73   U

      W Ff Ss Tt of Δ of U W of Δ of G73   Pns Qnf U

Instruction function Suit treatment to cast, forge creates a kind of work of form, see a picture 5.

Graph cutting of 5 fixed appearance is compound circulate

The instruction explains Δ I states X axial always retreats a knife to measure (radius is worth) ;

Δ K states Z axial always cancels knife amount;

D represents circular time;

Ns represents finish machining line the suitable serial number of the first block;

Nf states finish machining course is the last the suitable serial number of block;

The finish machining surplus that Δ U shows X way (the diameter is worth) ;

Δ W shows the finish machining surplus of Z direction.

Fixed appearance cutting is compound the characteristic that dictates circularly, cutting tool contrail is parallel the outline at workpiece, reason suits treatment to cast the preform that makes take shape with forge. Quantity of back penetration of a cutting tool passes X axis direction to always retreat a knife to measure Δ I and Z axis direction to always retreat a knife to measure Δ K to divide respectively get with circular time D. The cutting deepness of the set that always removes a knife to estimate Δ I and Δ K value and workpiece is concerned.

Cutting of form of use solid shape is compound circular instruction, should decide the dot that change a knife, loop nods A, cutting above all only then dot A ‘ the coordinate position with cutting terminus B. Example of the path on the analysis, a nods the circling point that it is abide, a ‘ the contour line that → B is workpiece, a → A ‘ the finish machining course that → B is cutting tool, the cutting tool when rough machining backs down from A dot nod to C, regressive distance is U /2 of Δ of Δ I + respectively, w of Δ of Δ K + , after such rough machining circulate W of U /2 of Δ of surplus of finish machining of automatic put apart, Δ .

Ordinal date Ns describes the line that cutting tool cutting machines to the block between Nf.

Graph compound loop applies cutting of 6 fixed appearance

Example 3 show 6 times like the graph, apply fixed appearance cutting process designing of compound loop instruction.

X of N010 G50 100 Z100

50 Z10 of X of N020 G00

18 W5 R10 of U of N030 G73

N040 G73 P50 Q100 U0.5 W0.5 F100 

N050 G01 X0 Z1

R of N060 G03 X12 W-6 6

N070 G01 W-10

N080 X20 W-15

N090 W-13

N100 G02 X34 W-7 R7

N110 G70 P50 Q100 F30

4.  Finish machining is compound circulate (G70)

Pns Qnf of   of statement form G70 

After instruction function dictates with G71, G72, G73 rough machining ends, loop of usable finish machining dictates, make cutting tool has the precision work of A-A’-B, (if pursue 1, graph 3, graph 5) .

The instruction explains Ns expresses to assign finish machining route the ordinal date of the first block;

Nf expresses to assign finish machining route the suitable serial number of the last block;   

Instruction of loop of G70 ~ G73 calls N(ns) to come between N(nf) block, the subprogram cannot be called in block among them.

5.  End panel drill is complex dictate circularly (G74)

Statement form G74 Re

            G74 X (U) Z (W) D Ff of Δ of K R of Δ of P Δ I Q 

Instruction function Can use at interrupted cutting, if course taking a knife pursues 7, be like a X (U) with P, R the value omits, can use at bore treatment.

Graph drill of 7 end panel is complex circulate

The instruction explains E represents the amount that retreat a knife;

X states the X coordinate that B nods is worth;

U states by A the increment coordinate to B is worth;

Z states the Z coordinate that C nods is worth;

W states by A the increment coordinate to C is worth;

Δ I states shift of X axis direction is measured, without sign;

Δ K states shift of Z axis direction is measured, without sign;

Δ D states in cutting bottom cutting tool go back is measured;

F shows feed rate.

Example 4 show 8 times like the graph, use end panel drill process designing of compound loop instruction.

Graph 8 Compound loop uses end panel drill

G50 X60 Z40

G00 X0 Z2

G74 R1

G74 Z-12 Q5 F30 S250

G00 X60 Z40

6.  Outside round grooving is compound circulate (G75)

Statement form G75   Re

G75   X (U) Z (W) D Ff of Δ of K R of Δ of P Δ I Q                                                     

Instruction function Use at end panel interrupted cutting, if course taking a knife pursues 9, be like a Z (W) with Q, R the value omits, can use at outside the interrupted cutting of round chamfer.

Graph 9 outside round grooving is compound circulate

The instruction explains E represents the amount that retreat a knife;

X states the X coordinate that C nods is worth;

U states the increment coordinate that nods to C by A dot is worth;

Z states the Z coordinate that B nods is worth;

W states the increment coordinate that nods to B by A dot is worth;

Other the meaning of each symbol and G74 are identical.

Round grooving is compound outside application circular instruction, if use cutting tool is grooving knife, this cutting tool has 2 point of a knife, the knife that set left point of a knife is this cutting tool dot, the circular start A that wants set cutting tool first before process designing and target nod D, if workpiece chamfer is wide the blade that is more than grooving knife is wide, want to consider the jackknife amount of edge contrail, the blade that makes cutting tool measures Δ K to be less than grooving knife in displacement of Z axis direction is wide, the blade of grooving knife is wide the jackknife volume that measures the difference of Δ K to be edge contrail with displacement of point of a knife.

5 graphs show example 10 times, round grooving is compound outside applying circular instruction process designing.

Graph 10 outside compound loop applies round grooving

G50 X60 Z70

G00 X42 Z22 S400

G75 R1

G75 X30 Z10 P3 Q2.9 F30 

G00 X60 Z70

7.  Whorl cutting is compound circulate (G76)

Statement form G76 Dmin Rd of Δ of Pm R A Q

G76 X (U) Z (W) D Ff of Δ of Ri Pk Q

Instruction function The craft sex that this whorl cutting circulates is more reasonable, process designing efficiency is taller, if course of whorl cutting loop and feed method pursue 11.

Graph 11 whorl cutting is compound circular course and feed law

The instruction explains M states finish machining repeats a time;

R expresses inclined to the quantity that retreat a knife the unit is counted (0.01~9.9f, it is one unit with 0.1f, with 00~99 two digit word is appointed) ;

A expresses point of view of point of a knife;

Δ D states first time is rough cut deep (radius is worth) ;

Degressive formula calculates cutting deepness D2 = Δ D;

      D3 = Δ D;

      D of Δ of Dn = ;

Every time thick cut deep: D of Δ of Δ Dn = – Δ D;

Δ Dmin shows depth of the smallest cutting, be less than Δ Dmin when Dn of cutting deepness Δ , take Δ Dmin to regard cutting as deepness;

X states the X coordinate that D nods is worth;

U states the increment coordinate that nods to D by A dot is worth;

Z states D nods Z coordinate value;

W states the increment coordinate that nods to D by C dot is worth;

I states the radius of awl whorl is poor;

K shows whorl height (X direction radius is worth) ;

D shows finish machining surplus;

F shows whorl lead.

Example 6 show 12 times like the graph, apply whorl cutting process designing of compound loop instruction (finish machining frequency is 1 times, inclined it is 4mm to the quantity that retreat a knife, point of a knife is 60 ° , the smallest cut take 0.1mm greatly, finish machining surplus takes 0.1mm, whorl height is 2.4mm, cut for the first time take 0.7mm greatly, pitch is 4mm, whorl trail is 33.8mm) .

Graph compound loop applies 12 whorl cutting

G00 X60 Z10

G76 P011060 Q0.1 R0.1

G76 X33.8 Z-60 R0 P2.4 Q0.7 F4