In current numerical control lathe, whorl cutting has method of two kinds of treatment commonly: G32 enters type cutting method and G76 continuously method of the inclined cutting that take form, as a result of cutting method different, process designing method is different, cause machining error to also differ. We are used in the operation on want anatomize, strive for treatment to give the part with tall precision.
Two kinds of process designing that machine a method dictate
G32 X (U) ＿ Z (W) ＿ F ＿ ;
Explain: X, Z is used at absolutely process designing; U, W is used at opposite process designing; F is pitch;
Deepness of cutting of G32 process designing allocates means to be worth for constant commonly, double blade cutting, its every time cutting deepness gives out by process designing of process designing personnel commonly.
G76P (M) (R) (A) Q (△ Dmin) R (D) ;
G76X (U) Z (W) R (I) P (K) Q (△ D) F (L) ;
M: Finish machining repeats a time; R: Pour horny width; A: Angle of point of a knife;
△ Dmin: Deepness of the smallest cutting, when every time cutting deepness (· of D of △ of N½- of △ D · (N-1) ½ ) when be less than △ Dmin, cutting deepness limitation is on this value; D: Finish machining allowance; I: The radius of whorl part is poor, be like I ＝ 0, for means of straight whorl cutting; K: Whorl tooth is tall;
△ D: The cutting deepness of first time cutting; L: Pitch.
Deepness of cutting of G76 process designing allocates means to be degressive type commonly, its cutting is odd blade cutting, its cutting deepness is calculated by control system give out.
Machining error analysis and use
G32 submits type cutting method continuously, because two side edge work at the same time, cutting power is greater, and the platoon cuts difficulty, because this is when cutting, two cutting blade wears away easily. It is when the whorl with cutting bigger pitch, because cutting deepness is bigger, edge wears away faster, cause screw center diameter to produce an error thereby; But the tooth form precision that its machine is taller, because this is general multi-purpose at small pitch thread machining. As a result of its cutting of cutting tool shift all relies on process designing to finish, machine program is so longer; Because edge wears away easily, because this treatment is medium,should accomplish diligent measure.
G76 is inclined method of the cutting that take form, because be treatment of odd side edge, treatment edge is injured easily and wear away, make the whorl face of treatment not straight, horn of point of a knife produces change, and cause tooth form precision poorer. But work for odd side edge as a result of its, cutting tool load is lesser, platoon bits is easy, and cutting deepness is degressive type. Accordingly, this treatment method applies to big pitch thread machining commonly. Because bits of platoon of this treatment method is easy, edge treatment operating mode is better, ask in whorl precision not high case falls, this treatment method is more convenient. Machining relatively when high accuracy whorl, can use two knives treatment to finish, machine a method to have thick car with G76 first already, machine methodological fine vehicle with G32 next. But should notice initial drop wants cutting tool accurate, otherwise easy chaos is buckled, cause a spare parts to discard as useless.
Cutting fluid is used
When turning whorl, use cutting liquid appropriately, can improve productivity and spare parts quality, the main effect of cutting fluid is as follows:
Can reduce the quantity of heat of the generation when cutting, reduce the machining error that causes as a result of temperature rise.
Film can be formed in metallic surface, reduce the attrition of cutting tool and workpiece, can sweep scrap, reduce workpiece surface surface roughness to be worth thereby, reduce cutting tool to wear away.
Cutting fluid enters metallic aperture, can help cutting tool successful cutting.
According to above action, my company passes a test for many times, used ” limited company of chemistry of Tai Lun spy ” of production ” CCF-10 of fluid of small emulsification cutting ” . Fluid of this kind of cutting is afterwards emulsion, synthesis after cutting fluid, the new generation product of fluid of water radical cutting, it overcame emulsion easy metamorphism, clean function difference and synthetic cutting fluid to erode difference of face of machine tool lacquer, lubricant function to wait for blemish, have good lubricant, refrigeration, clean, antirust function. Compare with other cutting fluid photographs, it has improve treatment efficiency, reduce motivation to use up, prolong cutting tool life, improve parts appearance bright and clean degree wait for effect.
Process designing citing
Machine the whorl of M36X1.5 for example, if the graph is shown 3 times, enter type cutting process designing continuously with G32 (every time cutting deepness is 0.2mm) :
N10 G00 Z234
N2O G00 X35.6
N30 G32 Z269 F1.5
N40 G00 X38
N50 G00 Z234
N60 G00 X35.2
N70 G32 Z269 F1.5
N80 G00 X38
N90 G00 Z234
N100 G00 X34.8
N110 G32 Z269 F1.5
N120 G00 X38
N130 G00 Z234
N140 G00 X34.38
N150 G32 Z269 F1.5
N160 G00 X300
G76 is inclined process designing of the cutting that take form:
G76 P010160 Q200 R0.05
G76 X34.38 Z269 P812 Q200 F1.5
Deepness of the smallest cutting is 0.02mm.
Deepness of first time cutting is 0.02mm.
Whorl tooth is 0.812mm high.
Can see the distinction of G32 process designing and G76 process designing apparently from inside above give typical examples, the precision that should see workpiece ask in the job will decide.