欧美人妻精品一区二区三区99,中文字幕日韩精品内射,精品国产综合成人亚洲区,久久香蕉国产线熟妇人妻

Drilling refers to the mechanical process of creating holes in solid materials using a drill bit. In general, when drilling on a drilling machine, the drill bit should perform two simultaneous movements:

Primary motion:?This involves the rotation of the drill bit around its axis (cutting motion).

Auxiliary motion:?This refers to the linear movement of the drill bit along the axis direction towards the workpiece (feed motion).

During drilling, the inherent flaws in the structure of the drill bit can, to some extent, affect the quality of the workpiece. The machining precision is generally below IT10, and the surface roughness is around Ra12.5μm, categorizing it as rough machining.

drilling holes

Drilling Operation Steps

1Marking Lines

Before drilling, familiarize yourself with the pattern requirements. Use a height gauge to mark the cross-center line at the hole position according to the dimensional requirements. The center line should be clear, accurate, and as fine as possible. After marking the lines, use a vernier caliper or a steel ruler for inspection.

2Drawing Inspection Grid or Circle

After marking the lines and ensuring they pass inspection, draw an inspection grid or circle with the hole’s center line as the symmetrical center. This serves as a reference for checking during drilling, facilitating the inspection and correction of hole positions.

3Pilot Hole Punching

After drawing the corresponding inspection grid or circle, carefully punch a pilot hole. Start with a small point, observe carefully in different directions from the cross-center line to ensure the pilot hole is at the intersection of the cross-center line. Finally, punch the pilot hole firmly, ensuring accuracy for drilling alignment.

4Clamping

Clean the machine table, fixture surface, and workpiece reference surface. Clamp the workpiece securely, ensuring a flat and stable clamping for easy observation and measurement. Pay attention to the clamping method to prevent deformation during clamping.

5Trial Drilling

It is essential to conduct a trial drill. Align the drill bit transversely with the center of the hole, drill a shallow pit at the center of the sample punched hole, visually inspect its correctness, and continuously adjust to align the pit with the inspection circle. If the deviation is small, apply force to gradually correct the position.

6Perforación

Machining the hole in metalworking generally involves manual feed operation. Once the trial broaching achieves the required positional accuracy, proceed with the broaching. During manual feeding, ensure that the feed force does not cause bending of the drill bit to prevent the hole axis from skewing.

What are the 5 Methods Available to Improve the Precision of Drilling? 1

Methods to Improve Drilling Accuracy

1Well-Sharpened Drill Bit as a Prerequisite

Before drilling, carefully select and sharpen the appropriate drill bit. The sharpened drill bit should have accurate positive rake angles, relief angles, and equal lengths for the two main cutting edges. Additionally, the two main cutting edges should be symmetrical with the centerline of the drill bit, and the main relief surfaces should be smooth. To facilitate centering and reduce wall roughness, appropriate grinding of the relief and main cutting edges is necessary (preferably rough grinding on a grinding wheel followed by fine finishing on an oilstone).

2Precise Marking as the Foundation

Accurate marking with a height gauge is fundamental. Ensure accurate dimensions, and when marking, create an angle of 40 to 60 degrees (along the marking direction) between the marking needle and the workpiece marking plane to produce clear and uniform lines. Select a well-machined reference surface for marking, ensuring its own flatness and perpendicularity to adjacent surfaces. After marking the crosshair lines for hole positions, use a center punch to mark the center point on the crosshair lines (the punch point should be small and accurately positioned) to facilitate centering during broaching.

3Correct Clamping is Key

For holes with a diameter less than 6mm, if precision is not critical, hand clamping of the workpiece for drilling is acceptable. For holes in the range of 6 to 10mm, if the workpiece is regular and flat, use a flat-nose pliers but ensure the workpiece surface is perpendicular to the drill spindle. When drilling larger diameter holes, the flat-nose pliers must be fixed with bolts. For larger workpieces with hole diameters exceeding 10mm, use a clamping method with a pressure plate for broaching.

4Accurate Centering is Crucial

After clamping the workpiece, do not rush to start drilling; instead, begin with centering. Centering can be static or dynamic. Static centering occurs before the drilling machine is started, aligning the centerline of the drill spindle with the intersection of the workpiece’s crosshair lines. While this method is safer and more convenient for beginners, it may result in lower drilling accuracy due to factors like the swing of the drill spindle. Dynamic centering is performed after the drilling machine is started, considering various uncertain factors, resulting in relatively higher accuracy.

5Thorough Inspection is Essential

Inspection helps discover the accuracy of the hole promptly, allowing necessary measures to be taken for correction. For holes requiring high accuracy, a processing technique involving drilling, reaming, and tapping is often employed. After drilling a small hole in the first step, use a caliper to measure the deviation from the center of the bottom hole to the reference surface. If the deviation is less than 0.10mm, adjustments can be made during reaming by increasing the drill bit’s rake angle and weakening the automatic centering effect, gradually pushing the workpiece in the correction direction. If the deviation exceeds 0.10mm, a round file can be used to smooth the sidewalls of the bottom hole, ensuring a smooth transition with the arc of the bottom hole.

Deja una respuesta

Tu dirección de correo electrónico no será publicada. Los campos obligatorios están marcados con *

国产成人精品久久久成人| 国产熟女视频一区二区三区| 把女生操出水的视频| 9999热精品免费视频| 午夜精品福利一区二区三区蜜桃p| 日日爱黄色毛片视频| 国产乱精品一区二区三区视频了| 久久一级高潮a免费| 欧美猛男一区二区三区快播| 激情五月六月婷婷俺来也| 日本高清一区二区三区在线观看| 国产精品亚洲一区二区三区下载| 巨屌抽插舔阴视频| 日本高清一区二区三区在线观看| 欧美人与性动交b欧美精品| 欧美巨屌虐无毛骚逼| 96精品久久久久久蜜臀浪| 国产黄片在线免费看| 欧美久久精品免费看C片| 操我好舒服用力视频| 可以免费看污污片的软件| 被医生添奶头和下面好爽| avtt天堂网先锋伦理| 波多野吉衣一区在线观看| 亚洲一区二区女同性恋免费看| 精品一区二区久久久久无码| 色噜噜AV亚洲色一区二区| 天堂丝袜人妻中文字幕在线| 一级特黄大片色欧美精品| 一区二中文字幕在线看国产一区| 9999热精品免费视频| 大鸡巴射在穴穴里的视频| 中文字幕av一区二区三区蜜桃| 日本亚洲免费不卡| 最新的亚洲欧美中文字幕| 男生舔女生下面黄色视频| 国产天美传媒剧免费观看| 欧美久久精品免费看C片| 精品一区二区三区成人免费视频| 精品一二三四区中文字幕| 国产区高清在线一区二区三区|