Common honing machine defects and causes are as follows: first, roundness error out of tolerance
The main reasons are as follows:
(1) The alignment error between honing spindle and workpiece hole is too large.
Measures: the coaxiality of spindle, guide sleeve and workpiece hole should be adjusted;
(2) The clamping force of the clamp is too large or the clamping position is improper;
Measures: adjust the clamping force or clamping position
(3) Uneven hole, high honing temperature or excessive honing pressure;
Measures: evaluate process and adjust honing pressure
(4) The hardness and material of inner hole are not uniform;
Measures: eliminate the hard spot of casting workpiece
(5) The coolant supply is uneven and insufficient, resulting in uneven cooling and heating on the inner hole surface;
Measures: optimize and adjust the amount of coolant and flushing position
(6) The ring error of process hole before honing exceeds I / 4 of honing allowance;
Measure: evaluate the roundness status of boring station or strong positioning honing station
(7) The floating connection of honing head is too loose, the speed is too high and the moment of inertia is large;
Measure: adjust the size of the floating amount until the joint can be vertical automatically
(8) If the stroke speed is too high, the roughness is unqualified.
Measures: adjust parameters according to workpiece status
3、 The straightness error of hole is out of tolerance
(1) The honing oil stone is too thick, and the guide bar interferes;
(2) The quality problem of the oilstone is that the abrasion is fast and the formability is not good. The oilstone can be treated for longer life;
(3) The straightness error of boring process hole is out of tolerance;
(4) The honing floating joint is not flexible. It affects the heterotropism of honing head;
(5) The clamping deformation of the workpiece is large;
(6) The reciprocating speed of honing is low and the coolant supply is uneven;
(7) The fixture is not well aligned with the spindle or guide sleeve,
3、 Hole size out of tolerance
(1) The honing heat is high and the size becomes smaller after cooling,
Measures: too much honing allowance and too long honing time; high honing speed and low reciprocating speed; blockage of oilstone and poor self sharpening; too fast honing quantity feeding and excessive honing pressure; insufficient coolant or poor cooling performance.
(2) The boring station is unstable, resulting in small size,
Measures: the surface quality of process hole before honing is poor, and the honing allowance changes greatly;
4、 Honing surface roughness can not meet the process requirements
(1) The circular speed of honing is too low and the reciprocating speed is too high;
(2) If the honing allowance is too small, the honing time is short, or the pressure is too large, the general honing allowance should be > 5; the honing pressure should be less than 0.5MPa;
(3) Honing cutting fluid has many impurities, low dryness, poor wettability and low flow rate;
(4) The surface roughness of boring process is too large;
(5) The honing stone is too hard and easy to block;
(6) The honing stone is too soft and the polishing is not good;
(7) If the material of the workpiece is too soft, hard or fine-grained or wax injected oilstone should be selected;
5、 Honing surface scratch
(1) The surface of honing oil stone is too hard and the structure is not uniform, and iron chips are easy to accumulate and scratch the surface after the surface of honing stone is blocked;
(2) the gap between honing head in hole is too small, and the chip which is not easy to be discharged from the hole is squeezed to scratch the surface;
(3) When the honing pressure is too large and exceeds the strength of the stone, the stone is crushed and scratched on the surface of the workpiece;
(4) When the honing head exits, the oilstone does not retract first, thus scratching the surface of the workpiece;
(5) If the guide sleeve is not aligned with the workpiece hole, the end of honing head is easy to swing when the honing head exits;
(6) If the oilstone is too wide, the iron filings are not easy to remove and fall off and accumulate on the surface of the oilstone to form hard spots and scratch the surface of the workpiece;
(7) There are too many impurities in the cutting fluid of honing machine, and the flow rate and I pressure force are too small;