Rolling residual magnetism technical conditions

Truck crane telescopic cylinder piston rod (pole) grinding waste-prone, according to our experience, the following measures to prevent waste.

1 piece of each point carefully measuring the amount of remaining mill

Should be based on the workpiece bending, deflection, dislocation and other data to determine whether the depth marks grinding.

(1) for grinding of not more than 0.50mm left the site operator can carefully measure the deflection, bending, dislocation, marks and other values. Leaving less than 0.20mm for grinding workpieces must consult the staff agreed before grinding.

(2) If the amount of deflection or bending amount exceeding one third of the parts to wear straightening after grinding.

(3) measuring the diameter of dislocation sites on both sides of both sides of the deflection data and the data available at the mill minimum diameter maximum value minus the yaw yaw position value, the amount of the difference is the actual grinding. Such as: dislocation at the grinding capacity of the smallest diameter 0.40mm, maximum deflection part of the deflection is 0.30mm, the actual grinding capacity equal to 0.40-0.30 = 0.10mm, grinding capacity is small, it is likely appear in the grinding burn conditions, resulting in waste.

(4) marks the site of deep, roll bearings grinding rasp the former is best to use local symmetry points (the most serious side parts) filed a two symmetrical facets, by filing off the site measured. If the measured diameter minus the diameter of marks after less than 0.20mm, should consult before grinding.

(2) properly handle grinding burns

(A) before grinding grinding according to the above requirements can be checked, if the coarse grinding sparks big, there are local burns, while after two reciprocating grinding burn site can not be eliminated, it should be carried out once the workpiece deflection values measurements. If the deflection values ??were lower than the preceding grinding limit, should be straightened. By straightening still not eliminated, must be scrapped.

(2) grinding sparks should pay attention to the changes, once burned, the workpiece Serve waste. Special minor burns, if measured yaw values ??below one-third of the amount of grinding, you can continue grinding; than one-third of which should be scrapped.

Burn causes and the wheel model, the workpiece material is also a relationship. Preventive measures are timely repair wheel, adjust the amount of feed (coarse or fine grinding, if the feed rate is too small will produce minor burns), add enough coolant and adjust the workpiece and wheel speed.

3 Carefully observe the spark

Once the grinding sparks too large to immediately retract. After all coarse grinding sparks phenomenon should not be interrupted, if the deflection off the fire area exceeds the amount of a quarter mill, to be straightened. Each wheel sparks near the ends of the workpiece gradually increased, the top should be checked whether the temperature is too high, if the top temperature is consistent with the workpiece to be tight at the top end. If the spark through bays larger, it indicates that the site of the top bracket is unreasonable, so that it temperature. Grinding sparks should not exist when the elephant stopped, if a serious fire off what should be measured yaw and grinding capacity, when the amount of deflection over a quarter mill grind it up.

4. Strictly control the quality and accuracy of processing

The spot diameter measured values ??are inconsistent, brackets and tailstock respond timely adjustments.

(1) through coarse, semi-fine grinding, the workpiece is not cylindrical tolerance. If ovality tolerance of the parts of a broken fire phenomenon, should be measured yaw value, if this value exceeds 30μm should try again after straightening mill; After several feed grinding, in total more than 50μm feed when Sparks will no longer off the fire, measured ovality should be zero; when measured ellipticity still exceeds tolerance, you should try again after grinding wheel dressing, if the ellipse is still not eliminated, the top hole should be checked for damage, research injuries ( At this point the workpiece surface showing polygonal).

(2) the surface after grinding and finishing the reasons presented Duoleng measures: If wheel has been blunt, should be trimmed; wheel if there is noticeable vibration, balance should be adjusted; head frame, motor frame vibration isolation facilities have been damaged, shall be repaired ; excessive vibration if the workpiece itself, should be properly deceleration; top too tight or too loose, it should be adjusted.

(3) If the coarse surface occurs when a large spiral, the reason is bad dresser, grinding wheel dressing time must be uniform and must not have significant single angle spark phenomenon blunt surface after grinding wheel prone to large spiral.

(4) grinding, the workpiece often appear galling, scratched and dirty coolant phenomenon. To prevent this phenomenon, the new wheel should be finishing with a wire brush a few times (pay attention to safety).

(5) When grinding the workpiece phenomenon taper, drum, saddle-shaped, both ends of a diameter larger or smaller, you should adjust the bracket, tailstock, wheel overrun and the number of workpieces at both ends of the workpiece and the grinding wheel travel time.

5 strictly controlled two top parts of the temperature

According to two top temperature changes are reasonable judgment leading tightness; generally top temperature slightly higher than the temperature of the workpiece as the standard.

(A) two leading causes of high temperatures: First, the top too tight, two center hole is top notch and the workpiece misalignment. If the top is too tight, first loosen the top, add the butter on the two center hole and then adjust the tightness of the top.

(2) If there is a top temperature is too high, then the top center hole with the workpiece misalignment.

(3) When the temperature of the top two consistent temperature of the workpiece, the workpiece two polygonal phenomenon does not occur, and more uniform spark, this time to continue the grinding. As part two phenomena appear Duoleng, you should look at the top tight, if the workpiece does not burn, you can wear them all. When the workpiece two spark uneven, they will bear about the top end.