Common problems and solutions in processing
1. The pore diameter is reduced
Causes: the design value of reamer outer diameter is too small; the cutting speed is too low; the feed rate is too large; the main deflection angle of reamer is too small; the selection of cutting fluid is not appropriate; the worn part of reamer is not worn off during grinding, and the elastic recovery reduces the aperture; when reaming steel parts, if the allowance is too large or the reamer is not sharp, it is easy to produce elastic recovery, so that the aperture is reduced and the inner hole is not round and the aperture is not qualified.
Solutions: change the outer diameter of reamer; increase the cutting speed; reduce the feed rate; increase the main deflection angle; select the oil-based cutting fluid with good lubrication performance; exchange reamers regularly and grind the cutting part of the reamer correctly; when designing the reamer size, consider the above factors or take the value according to the actual situation; make experimental cutting and take appropriate allowance to sharpen the reamer 。 Deep hole drilling and boring machine
2. The pore diameter increases
Causes: the design value of reamer outer diameter is too large or the reaming cutting edge has burr; the cutting speed is too high; the feed rate is improper or the machining allowance is too large; the reamer's main deflection angle is too large; the reamer is bent; the reamer edge is stuck with chip lump; the swing error of reaming edge is out of tolerance during grinding; the cutting fluid is not selected properly; the surface of taper shank is not wiped clean or the conical surface is damaged when installing reamer; After the flat tail of the taper shank is offset and installed into the spindle of the machine tool, the taper of the taper shank interferes; the spindle is bent or the bearing of the spindle is too loose or damaged; the reamer floats inflexibly; the force of both hands is uneven when the shaft is different from the workpiece and when reaming the hole by hand, which makes the reamer shake left and right.
Solutions: according to the specific situation, reduce the reamer outer diameter; reduce the cutting speed; properly adjust the feed rate or reduce the machining allowance; properly reduce the main deflection angle to straighten or scrap the reamer that cannot be used; carefully trim the reamer to be qualified with oilstone; control the swing error within the allowable range; select the cutting fluid with good cooling performance; before installing the reamer, the reamer taper shank and machine tool spindle must be adjusted The oil stain inside the taper hole shall be cleaned up, and the bumps on the cone surface shall be polished with oilstone; the flat tail of reamer shall be grinded, and the main shaft bearing shall be adjusted or replaced; the floating chuck shall be readjusted and the coaxiality shall be adjusted; attention shall be paid to the correct operation.
3. The reamed inner hole is not round
Causes: the reamer is too long and rigid, which causes vibration during reaming; the main deflection angle of reamer is too small; the reamer cutting edge is narrow; the reaming allowance is biased; there are gaps and cross holes on the inner hole surface; there are sand holes and air holes on the surface of the hole; the spindle bearing is loose, there is no guide sleeve, or the clearance between reamer and guide sleeve is too large, and the workpiece is deformed after unloading due to the tight clamping of thin-walled workpiece.
Solutions: the reamer with unequal pitch can be used for the reamer with insufficient rigidity. The installation of the reamer should adopt rigid connection to increase the main deflection angle; the qualified reamer should be selected to control the hole position tolerance in the pre-processing process; the reamer with unequal pitch should be used with a longer and more precise guide sleeve; the qualified blank should be selected; when the reamer with equal pitch is used to ream more precise holes, the spindle of the machine tool should be used If the clearance is adjusted, the fit clearance of guide sleeve should be higher or appropriate clamping method should be adopted to reduce the clamping force.
4. The position accuracy of reamed hole is out of tolerance
Causes: the guide sleeve is worn; the bottom end of the guide sleeve is too far from the workpiece; the length of the guide sleeve is short, the precision is poor and the spindle bearing is loose.
Solutions: replace the guide sleeve regularly; lengthen the guide sleeve to improve the matching precision between the guide sleeve and reamer; timely repair the machine tool and adjust the spindle bearing clearance.