1、COMMON CAUSES OF CENTERLESS GRINDING ERRORS 無心磨削錯誤的常見原因Burn Marks on the Workpiece 工件灼傷標記工件灼傷標記Cutting on trailing edge of the wheel (Spiral Burn) 尾緣切口（螺旋紋） Insufficient coolant (Shadow and Spots) 冷卻液不足（陰影和斑點）Dull or flat diamond (Shadows and Glazed Grinding Wheel) 金剛筆太鈍（陰影和砂輪釉面）Grinding wheel dress

2、ed with too slow a diamond traverse rate (Glazed looking Grinding wheel) 砂輪修整時金剛筆速度太慢（砂輪呈現釉面）Wheel too hard 砂輪太硬Too heavy stock removal 磨削量過大Chatter顫振顫振Blade not properly clamped 托板沒固定好Glazed wheel caused by dull diamond, wheel too hard, grit size too fine or dressing rate too slow 釉面砂輪成因：金剛筆太鈍、砂輪太硬

3、、砂粒太細、修整速度太慢。Work too high above center 工件離中心線太遠Blade too thin or warped 托板太薄或卷曲Wheel out of balance 輪子失去平衡Motors out of balance 電機失去平衡Stock removal too heavy (Line of Cut Not Set Correctly) 磨削量太大 （切削路線不直）Chatter Cont. 顫振顫振Machine leveling screws not adjusted for even torque when machine is finally

4、leveled 機器最后調平后螺母上緊程度不均Blade being used is too long for the width of the wheel 托板相對于輪子寬度太長Outside “floor harmonics” 機器外面“地面諧波”Grinding wheel mount fits loosely on spindle 砂輪松動Blade angle too steep (300 Standard) 托板上表面角度太陡（標準30）Erratic Sizing 尺寸不穩定尺寸不穩定Work improperly rough ground 粗磨精度不夠Parts overhea

5、ting during cut, due to improper wheel or insufficient coolant 磨削時由于砂輪不好或磨削液不足桿受熱過度Loose work support blade 托板松動Insufficient lubrication on lower slides causing slides to hang or jump (infeed). Too much lubrication oil (Thrufeed) 下滑塊潤滑不夠導致進刀時滑塊每次進刀量不一致（切入磨）。潤滑油過多（通磨）Gibs not properly adjusted on upp

6、er and lower slides 上下滑塊沒有調整好。Erratic Sizing Cont.尺寸不穩定尺寸不穩定Regulating wheel camming 導輪凸輪板問題Soft wheel 輪子太軟Wear on infeed screw and nut 進給螺釘螺母磨損Infeed lever not held tight (for thrufeed work) 進給裝置沒有固定好Improper tension on backlash spring 消隙彈簧張力不合適Feed Lines 進料線紋進料線紋Grinding wheel not relieved on exit

7、 side 砂輪出口端沒有修整好Work guides not properly set 夾板沒調好On long bar fixtures excessive pressure on work piece by roller hold-down 長軸夾具- 工件受壓過大Finish光潔度光潔度Setup not correct 設置錯誤Dirty or insufficient coolant 冷卻液太臟或不足Diamond dressing traverse rate too fast 修整速度太快Pick-up on blade 托板上Loose, cracked or dull dia

8、mond 金剛筆松動，裂開或太鈍Regulating wheel SFM excessive 導輪SFM太大 Unbalanced wheel 輪子平衡性不好Finish Cont 光潔度光潔度Blade not tight in work rest 托板沒有上緊Work too high above center 工件位置太高Regulating wheel not tight on its mount 導輪松動Erratic movement of truing attachments 修整器運動不穩定Improper wheel grade 輪子不合適Oil on face of whe

9、el 輪子表面有油Blade angle too steep 托板上表面太陡Low Ends on Work Chamfered 工工件錐度件錐度-兩端磨出倒角兩端磨出倒角Work guides deflected toward regulating wheel 夾板向導輪偏離Face of regulating wheel not straight at work contact point (truing device worn or not on correct angle) 導輪與工件的接觸面不平 （修整器磨損或修整角度不當）Low Centers High Ends 中間凹進中間凹進

10、 兩端凸出兩端凸出Work guides deflected toward grinding wheel 夾板向砂輪偏移Face of regulating wheel not straight at work contact point (truing device worn or not on correct angle)導輪接觸工件的表面不平 （修整器磨損或修整角度不當）Out of Round Work 工件圓度不好工件圓度不好Regulating wheel not dressed round 導輪沒有修整圓 Flat diamond 金剛筆太鈍Work not high enoug

11、h above center 工件位置太低Interrupted cut due to keyways, holes, flats, etc. 工件上有鍵槽、孔、或者平面等，干涉切削Work piece bowed 工件彎曲Not enough stock to round up 磨削量太小Out of Round Work Cont. 圓度差圓度差Regulating wheel speed too slow or too fast 導輪速度太慢或太快Out of balance work piece 工件平衡性不好Regulating wheel loose on mount 導輪松動Bl

12、ade angle not steep enough 托板上表面角度不夠大（不夠陡）Grinding wheel not properly graded for job 砂輪不適合On infeed only, end stop or ejector may be worn on locating surface 僅適用于切入磨：彈出器可能磨損Taper 錐度錐度Work guides not set properly 夾板沒有調好Dirt under workrest or blade 托架或托板有污染Loose gibs 夾條松動Failure to keep parts butted e

13、nd to end on thrufeed 工件之間沒對接好Too much feeding pressure (race grinding fixture) 進給壓力過大Non-uniform spark out time from one piece to the next (infeed setup) 光磨時間不均（切入磨設置）Wheel not cutting freely (part expands due to surface temperature immediately behind lading end. This results in tapered part with l

14、eading end high.) 砂輪切削不暢 （表面溫度升高導致工件膨脹。 這將導致工件的錐度，件前端過高）。Dull Diamond Grinding Wheel Truing Attachment 金剛筆太鈍金剛筆太鈍 砂輪砂輪修整器修整器Diamond nib not turned periodically 金剛筆沒有定期車削Excessive infeed of diamond (should not take more than 0.001” depth of cut under normal conditions) 金剛筆進的太多 （一般情況下，每次的深度不超過0.001英尺）

15、Fish Tails 末端呈魚尾狀末端呈魚尾狀Dirty coolant 冷卻液太臟Loose grit in wheel 輪子上砂粒沒粘緊Grinding Wheel Too Hard 砂輪太硬砂輪太硬May cause burn marks 可能導致桿上有燒傷痕跡Can cause squeal because it is not free cutting 刺耳的噪音Glazing may occur on wheel face 砂輪表面出現釉面Soft materials may “load” wheel 材質軟的材料可能附在砂輪上Often produce chatter on wor

16、k piece 制造噪音Sizing trouble, due to no spark out 尺寸問題May cause heat checks or cracks 可能導致熱龜裂或裂開Grinding Wheel Too Soft 砂輪太軟砂輪太軟Sizing trouble, because wheel breaks down rapidly 尺寸問題，因為砂輪磨損過快Chatter may develop 可能有顫振High Above Center of Workpiece 工件位置太高工件位置太高If too high, chatter can develop 位置太高時，可能顫振

17、Optimum rounding action will not occur if center height is too low 中心高度太低時達不到最優圓度Intermittent Cut 間歇性磨削間歇性磨削Grinding wheel not correctly trued 砂輪沒修整好Regulating wheel “camming” 導輪形狀沒修整好Warped work piece 工件彎曲Jumpy Truing Device 修整器顛簸修整器顛簸Slides not lubricated properly 滑塊潤滑不當Gib adjusted improperly 夾條沒

18、調好Loading of Wheels 輪子粘上雜質輪子粘上雜質See grinding wheels too hard (3 above) 見砂輪太硬部分Wheel to fine. Larger grain size allows more chip clearance. 需要細砂輪。砂粒越大，間隙越大，越容易塞進雜質Ineffective cutting fluid due to the lack of lubricity of cutting fluid, chips adhere to grit of wheel. 切削液失效-由于切削液潤滑性能不好，磨屑附在砂料上。Change t

19、o coolant with greater lubricity or increase amount of concentration in mix. 應更換潤滑性能更好的磨削液或增大濃度。Pick-up on Blade 托板上有雜質托板上有雜質Cutting fluid no lubricating work-to-blade contact point. Use cutting fluid with greater lubricity or increase concentration. 磨削液潤滑性能不好。 請用潤滑性能更好的磨削液或增大濃度。Blade too hard for m

20、aterial being ground (use cast iron or bronze blade) 托板太硬 （使用鑄鐵板或銅板）Regulating Wheel “Camming” 導輪形狀沒修整好導輪形狀沒修整好Collet screws loose 夾筒螺釘松動Bearings worn 軸承磨損Regulating wheel spindle eccentric or out of round 導輪主軸偏心或不圓Spiral Chatter 螺旋紋螺旋紋 Hard spots in wheel 輪子上有堅硬凸起Chipped edge of wheel 輪子棱破損Loose machine elements 機器部件松動Straightness 垂直度垂直度Work not straightened sufficiently before grinding 磨前沒有調直Insufficient grinding stock left on work piece ，磨前工件尺寸不夠Too much stock removal on firs