Numerical control machine tool machines dimension not to stabilize case study

The join between axis of servo electric machinery and guide screw becomes loose, cause guide screw beforehand electric machinery is not synchronous, occurrence on size error. When detecting, need to make good mark on the shaft coupling of servo electric machinery and guide screw only. Make a round trip with faster fold shuttle table (or tool carrier) , as a result of workbench (or turn tower) inertial action, will make the two end of shaft coupling appear to move relatively apparently. This kind of breakdown changes to be treatment dimension to change to a direction only now normally, need to tighten shaft coupling screw solid to be able to eliminate equably only. 2.

Lubricate between ball guide screw and nut undesirable, make workbench (or tool carrier) athletic obstruction increases, cannot completely accurate executive shift dictates. Normally expression is this kind of breakdown inside a few limits spare parts dimension is random fluctuant, need to be able to remove lubricant improvement trouble only. 3.

Machine tool workbench (or tool carrier) mobile resistance is too great, it is commonly set had adjusted surface of slideway of close, machine tool lubricant and undesirable be caused by. Average performance is this breakdown phenomenon inside a few limits spare parts dimension is random fluctuant, need to will set a readjust and improve slideway to lubricate only can. 4.

Scroll bearing wears away or adjust undeserved, cause athletic resistance too big. This breakdown phenomenon also is behaved normally it is for dimension inside a few limits random is fluctuant. Need to will wear away to bearing changes and be adjusted seriously only, breakdown can eliminate. 5.

Guide screw clearance or clearance compensation are undeserved, compensate a value to be able to remove trouble through adjusting clearance or change clearance. Treatment dimension does not stabilize kind of breakdown to judge 　 of maintenance 　 　 1.

Workpiece size is exact, the surface is bright and clean reason of breakdown of 　 of the 　 that spend difference: Cutting tool point of a knife is damaged, not sharp; The machine tool produces resonance, place not smooth; The machine tool has creeping appearance; Treatment technology is bad. Solution: Cutting tool wears away or damage hind is not sharp, the cutting tool with grind a knife afresh or choose better is opposite afresh knife; The machine tool produces resonance or place not smooth, adjust a level, lay next foundations, fixed and smooth; What mechanical generation crawls is former because procrastinate board slideway wears away fierce, guide screw ball wears away or become loose, the machine tool should notice to maintain, iron wire should be swept after commuting, add lubricating oil in time, in order to reduce attrition; The choice suits the cooling fluid that workpiece machines, below the condition that can obtain other working procedure to machine a requirement, choose higher main shaft rotate speed as far as possible. 2.

Workpiece produces account of breakdown of 　 of 　 of phenomenon of taper differ in roll end diameter: The standard that the machine tool sets was not adjusted good, one tall one low, generation is placed not smooth; When turning grows an axis, contributive data is harder, cutting tool penetration of a cutting tool is deeper, create appearance letting a knife; Tailstock thimble and main shaft are not homocentric. Solution: Use gradienter adjusts the level of the machine tool to spend, lay next solid groundwork, had secured the machine tool raise its tenacity; Choose sound technology and proper cutting feed to avoid cutting tool to suffer force to let a knife; Adjust tailstock. 3.

Driver is phasic the lamp is normal, and the reason of breakdown of 　 of 　 of work measure size that treatment comes out: The machine tool procrastinates board long-term high speed moves, bring about filar lever and bearing to wear away; The repetition of tool carrier locates precision produces deviation in be used for a long time; Procrastinate board every time can accurate return treatment start, but treatment work measure still changes. This kind of phenomenon is caused by main shaft commonly, the high speed roll of main shaft makes bearing wears away serious, bring about treatment dimension to change. Solution: Lean in tool carrier bottom with dial gauge, edit program of a fixed loop through the system at the same time, the examination procrastinates board repeat fixed position precision, adjust filar lever clearance, change bearing; Repeat fixed position precision with what dial gauge checks tool carrier, adjust machinery or change tool carrier; Detect with dial gauge after processing work accurate return program start, it is OK to be like, overhaul main shaft, change bearing. 4.

Work measure and real measure differ a few millimeter, or some axial has reason of breakdown of 　 of 　 of very big change: The rate of fast fixed position is too rapid, drive and electric machinery response do not come; In long-term attrition loss hind pulls board silk lever and bearing mechanically to get stuck too closely dead; After tool carrier changes a knife too loose, the lock is incompact; Editing process is wrong, head, end does not have echo or did not cancel a knife to filled to end; Electronic gear of the system is compared or step pitch horn installs a mistake. Solution: Rate of fast fixed position is too rapid, adjust the rate of GO appropriately, cutting adds decelerate to spend make with time driver and electric machinery leave regular job in rated running frequency; After occurrence machine tool wears away generation procrastinates board, bearing of filar lever crane gets stuck too closely dead, criterion must readjust rehabilitate; After tool carrier changes a knife too loose a reversing time of examination tool carrier is contented, whether does the turbine worm that checks tool carrier interior wear away, clearance whether too big, whether does installation cross a pine to wait; If program reason is caused, must modify a program, ask to improve according to workpiece blueprint, choose sound treatment technology, by the statement that reflects a manual the requirement writes proper program; Whether to if discover dimension deviation checks systematic parameter too big,install reasonable, especially whether is the parameter such as electronic gear and step pitch horn destroyed, appear this phenomenon can be measured through hitting dial gauge. 5.

Effect of treatment circular arc is not ideal, dimension is less than a reason of 　 　 breakdown: The jackknife of oscillatory frequency brings about resonance; Machine craft; Parameter setting is unreasonable, feed rate is too old, make circular arc treatment loses a condition; Filar lever clearance causes greatly become loose or filar lever causes too closely lose a condition; Synchronous belt wears away 　 　 solution: Find out generation syntonic component, change its frequency, avoid resonance; Consider the treatment craft of workpiece material, program of reasonable work out; Enter electric machinery to the pace, treatment rate F cannot have been installed big; Whether is the machine tool installed firm, place smooth, procrastinate board after whether wearing away, tighten too, clearance increases or tool carrier becomes loose etc; Change synchronous belt. 6.

In batch production, now and then reason of breakdown of 　 of 　 of occurrence workpiece out of tolerance: Must check tool clamping apparatus seriously, and the operation method that considers handlers, reach the dependability that holds clip, because install the dimension change that clip causes, must improve tool to make the worker avoids to make appearance of miscarriage of justice cursorily artificially as far as possible; Numerical control system may get the wave motion of outside power source or after be disturbed, automatic generation disturbs pulse, pass drive to cause drive to accept redundant pulse drive to electric machinery is snatched or take an appearance less, understanding grasps its pattern, adopt the measure of a few interference rejection as far as possible, be like: The line of the strong report cable that strong electric field disturbs and weak report signal is kept apart, the absorption that joins interference rejection capacitance and use screen line segregation, additional, whether does examination ground wire join firm, ground connection contact is the most intimate, adopt all interference rejection measure to avoid a system to suffer interference. 7.

Treatment of working procedure of workpiece some line has change, other each working procedure size is exact reason of 　 　 breakdown: The parameter of this block program is reasonable, whether be inside booked contrail, whether does process designing format accord with 　 of manual requirement 　 solution: Random tooth appears when whorl block, pitch is incorrect, the periphery that associates to treatment whorl immediately is configured (coder) the objective element with this function. 8.

Every working procedure of workpiece has the reason of breakdown of phenomenal 　 　 that increase by degrees or decreases successively: The program writes a mistake; Systematic parameter setting is unreasonable; Configuration setting is undeserved; Mechanical drive disk assembly has the 　 of metabolic breakdown 　 with seasonal pattern solution: Whether does the statement that inspection program uses press the requirement contrail that the manual sets to carry out, can be judged through hitting dial gauge, after the start that locates dial gauge in the program lets a program end, procrastinate board whether to return start position, repeat executive even if to observe its result again, grasp its pattern; Whether is inspection system parameter installed reasonable or be thought to alter; Concerned machine tool configures only on parameter of join computation coupling consideration to whether accord with a requirement, pulse equivalent is accurate; Part of drive of examination machine tool has damage, gear coupling is even, whether does the examination exist periodic, regularity breakdown phenomenon, if have an examination,its key gives partly eliminate. 9.

The dimension change that the system causes does not stabilize reason of 　 　 breakdown: Systematic parameter setting is unreasonable; Working voltage is not stable; The system suffers exterior interference, bring about a system to lose a condition; Already increased electric capacity, but the impedance between system and driver does not match, bring about useful signal to lose; Signal is transmitted between system and driver abnormal; Systematic attaint or in-house breakdown. Solution: Rapid rate, quicken time to whether pass big, main shaft rotate speed, cutting rate is reasonable, whether the parameter of handlers is revised bring about systematic performance to change; Add equipment of outfit stabilized voltage; Ground wire decides reliable already join, in driver pulse output contact place adds interference rejection to absorb capacitance; Choose proper capacitance model; Whether does the signal jumper between inspection system and driver take screen, join is reliable, check a system to whether is pulse happening signal lost or increase; Send a factory to maintain or change advocate board. CNC Milling CNC Machining