What are the types of CNC threading instructions?

CNC threading instructions are: G32, G92, G76, G82 The difference between these three instructions:

G32 is a constant pitch thread machining.

G72 is Rowan.

Compound fixed cycles.

G82 is a multi-head threaded composite fixed cycle.

The G92 is a threaded single shape fixed loop.

FANUC system CNC lathe thread cutting instruction (Huazhong, Guangzhou CNC and FANUC system are almost the same).

g32 x f ；

g32 z f ;(X and Z are the coordinates of the target point, and F is the pitch, which belongs to a single program segment pass, similar to the G01 route, one program segment and one action).

g92 x z f ;

x ;x ;(X, Z is the target point coordinates, F is the pitch, belongs to a single cycle of the tool, a program section has four actions: feeding, turning, retracting, and returning).

G76 is a thread-cutting compound cycle, a program segment with multiple actions until the end of turning to the end of X and Z, the format and meaning are as follows.

g76 p020060 q150 ；

g76 x z p q r f ；

The first line can be applied, q is the amount of knife eaten each time, in microns. r is the fine turning allowance, radius value).

The second line: x and z are the coordinates of the target point, p is the height of the tooth profile (p is in microns, for example, p1000 means 1mm), q is the amount of the first knife (the unit is microns, for example, q150 is the radius difference between the start and end points of the thread you have programmed, and f is the pitch (lead).

g76 p m rα qδdmin rd;

g76 x(u) z(w) ri pk qδd ff;

Description: m: number of finishing repetitions (01 99);

r: oblique retract (to the first gear, can be specified with 00 99 two-digit number;

There are six types of knife tip angles, which can be selected as °, which are specified by two digits;

dmin: minimum depth of cut;

d: finishing allowance;

x(u) z(w): thread end coordinates;

i: the radius difference of the conical thread, if i=0 is a cylindrical thread,;

k: thread tooth height (directional radius value), usually positive, expressed as no decimal point;

d: the first coarse depth of cut (radius specified), expressed in the form of no decimal point;

f: Threaded lead.

The second format.

g76x(u)__z(w)__i__k__d__f__a__；

where x and z are the coordinate values of the end point of the thread;

u, w: the coordinate increment of the end point of the thread relative to the beginning of the cycle;

i: is the radius difference between the start point and the end point of the taper thread, when i is 0, the cylindrical thread is processed;

k: is the height of the thread profile (radius value), usually a positive value;

d: is the amount of back eating knife (radius value) of the first feed, usually a positive value;

f: command thread lead;

A: Thread profile angle.

CNC threading instruction programming.

Types of threading: inner (outer) cylindrical threads, inner (outer) conical threads, single and multi-head threads, constant pitch and variable pitch threads.

2. Classification of thread processing instructions: Equal pitch thread turning instruction (G32), simple thread turning cycle instruction (G92), thread turning compound cycle instruction (G76), 3. Equal pitch thread cutting instruction G32, the basic thread cutting method is shown in the figure. Programming format G32 x(u) z(w) f: x(u), z(w) - the coordinate value of the end point of the thread cut; When x is omitted, it is cylindrical thread cutting, and when z is omitted, it is end face thread cutting; When x and z are not omitted, it is taper and thread cutting; (The x coordinate value is determined according to the "Mechanical Design Manual" lookup table) f - thread lead.

Attention should be paid to setting enough upward speed advance section δ1 and reduced speed retract section δ2 at both ends of the thread cutting. Figure: Cylindrical thread cutting.

Use the G92XZF command: X, Z are the target points, and the coordinates F represent the pitch, which belongs to a single program segment of the knife, similar to the G01 route, one program segment and one action.

CNC threading instruction format requirements:

G32 is used to process single-head equal-pitch straight threads and single-head equal-pitch tapered threads: N, G32, X(U), Z(W), F, M, T, S;

G92 equal pitch straight thread and tapered thread single shape fixed cycle: N, G92, X(U), Z(W), R, M, T, S;

r: oblique retract (to the first gear, can be specified with 00 99 two-digit number;

There are six types of knife tip angles, which can be selected as °, which are specified by two digits;

CNC threading instructions are: G32, G92, G76, G82 The difference between these three instructions:

G32 is a constant pitch thread machining.

G72 is a Rowan compound fixed cycle.

G82 is a multi-head threaded composite fixed cycle.

The G92 is a threaded single shape fixed loop.

Thread cutting cycle G92: In the FANUC CNC system, there are two processing instructions for CNC lathe thread cutting cycle machining:

G92 straight cutting and G76 diagonal cutting. Due to the different feeding methods of cutting tools, these two processing methods are different, and their programming methods are also different, and the machining accuracy of the thread section after the workpiece is machined is also different.

Command format: g92 x(u) z(w) f j k l ; Metric straight thread cutting cycle).

g92 x（u）_ z（w）_ i_ j_ k_ l ；inch straight thread cutting cycle).

g92 x（u）_ z（w）_ r_ f_ j_ k_ l ；Metric taper thread cutting cycle).

g92 x（u）_ z（w）_ r_ i_ j_ k_ l ；inch taper thread cutting cycle).

Command function: From the starting point of cutting, radial (X-axis) approach and axial (Z-axis or X, Z-axis at the same time) cutting are carried out to achieve equal pitch.

Straight thread and taper thread cutting cycles. Execute the G92 instruction and there is a thread tailing process at the end of the threading:

At a fixed length from the end of the thread cut (called the thread's tail length), the x-axis retracts along the x-axis while the thread interpolation continues.

The directional exponential or linear (set by the parameters) accelerates the exit, and after the z-axis reaches the end of the cutting shinmori, the x-axis retracts at a rapid moving speed.