Shallow talk about numerical control lathe the treatment of common thread

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OK on numerical control lathe turning the metric system, inch make, modulus and diameter are abstemious whorl of 4 kinds of standards, no matter turning which kind of whorl, the campaign that must keep strict between lathe main shaft and cutting tool concerns: Namely main shaft every turn (namely workpiece turns) , cutting tool should move equably one (of workpiece) the distance of lead. Pass the analysis of pair of common thread below, enhance the knowledge of pair of common thread, so that better treatment is common whorl. One, the lathe of dimension analysis numerical control of common thread needs a series of measure to the treatment of common thread, the dimension computation analysis that place of common thread machining requires basically includes the following two respects: 1, tooth of thread machining of consideration of diameter of the workpiece before thread machining expand quantity, d/d of diameter of the workpiece before thread machining - 0.

1P, namely whorl old way is decreased 0.

1 pitch, be out of shape according to material commonly capacity is small take older than whorl way small 0.

1 to 0.

5. 2, whorl of quantity of thread machining feed adds feed to measure way of bottom of OK and referenced whorl, namely whorl knife is final feed position. Whorl trail is: Old way - 2 times tooth is tall; Tooth tall =0.

54P (P is pitch) the feed quantity of thread machining should decrease ceaselessly, specific feed quantity undertakes choosing according to cutting tool and working material. 2, the outfit knife of common thread tool and low to knife lathe tool is installed exorbitantly or passing exorbitant, criterion penetration of a cutting tool arrives when certain deepness, of lathe tool hind knife face withstands workpiece, increase attrition power, bend workpiece top even, create the appearance that gnaw a knife; Too low, cut bits not easy eduction, the direction of lathe tool radial load is work center, add a horizontal stroke to pass into guide screw and nut clearance big, cause deepness of penetration of a cutting tool ceaseless and automatic incline to is deepened, raise workpiece thereby, appear gnaw a knife. Right now, answer to adjust lathe tool height in time, make the axes of its point of a knife and workpiece tall (can use tailstock center to the knife) . When thick car and half fine vehicle, position of point of a knife is higher than a center of workpiece 1 % D is controlled (D expresses to be machined workpiece diameter) . The tigidity that workpiece outfit places itself of not firm workpiece cannot bear the cutting force when turning, had produced big deflection consequently, the centre height that changed lathe tool and workpiece (workpiece by drive up) , form cutting deepness dash forward add, appear gnaw a knife, answer to originally workpiece outfit clip right now, can use tailstock tip to wait, in order to increase workpiece tigidity. The method has pair of knives of common thread try cut a law to be mixed to the knife be opposite automatically to Dao Yi knife, can try with cutting tool directly cut pair of knives, also can set work with G50 at 0 o'clock, move with workpiece setting workpiece undertook pair of knives at 0 o'clock. Thread machining is not very tall to knife requirement, especially Z to do not have rigid limitation to the knife, can machine a requirement according to process designing and decide. 3, the process designing treatment of common thread is in current numerical control lathe, whorl cutting has method of 3 kinds of treatment commonly: G32 enters type cutting method, G92 to enter type cutting method and G76 continuously 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. 1, 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. 2, G92 simplified into type cutting method continuously process designing, relatively G32 instruction improved efficiency. 3, 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. 4, observation can be passed after thread machining is finished quality of whorl of whorl tooth judgement takes step in time, when whorl tooth when the tip is not pointed, the approach that increases a sword can make whorl old way increases instead, increase to the quantity inspects material plasticity and be decided, the approach that the sword increases when when the tooth the top already was nibbed is old diameter is reduced into scale, according to this one characteristic should treat the approach of whorl correctly, prevent to discard as useless. 4, of common thread detect to average level whorl, use whorl ring gauge or plug guage to measure. When the whorl outside measuring, if whorl " carry too " ring gauge as it happens comes back into, and " end stop " ring gauge comes back to be not entered, the thread that shows a treatment accords with a requirement, conversely unqualified. Measure inside when whorl, use whorl plug guage, undertake metrical with same method. Other measure still can be used to undertake metrical outside be being measured except whorl ring gauge or plug guage, measure with whorl micrometer measure screw center diameter, measure tooth of echelon screw center diameter with vernier calipers of transverse tooth thickness thick with transverse tooth thickness of worm part way, use quantity needle to measure a law to measure screw center diameter according to 3 needles. CNC Milling