Drills are the most commonly used tools in hole processing. They are widely used in the intelligent manufacturing of vertical cnc machining centers 850, especially for the processing of cooling devices, tube sheets of power generation equipment, steam generators and other parts. The applications are particularly wide and important. So how does the machining center perform detailed drilling operations?
First of all, we must understand the characteristics of drilling and cutting effects.
According to different workpiece shapes, materials, structures, functions, etc., drill bits can be divided into many types, such as high-speed steel drill bits (twist drill, group drill, flat drill), solid carbide drill bit, indexable shallow hole drill, deep hole Drills, nesting drills and interchangeable bit drills, etc. The drill bit usually has two main cutting edges, and during machining, the drill bit performs cutting while rotating. The rake angle of the drill is getting larger and larger from the central axis to the outer edge. The cutting speed of the drill is higher the closer to the outer circle, and the cutting speed is gradually reduced toward the center, and the cutting speed of the rotation center of the drill is zero.
Two major problems that need to be solved in drilling-chip breaking and chip removal
The cutting of the drill is carried out in a hole with a narrow space, and the chips must be discharged through the groove of the drill. Therefore, the shape of the chip has a great influence on the cutting performance of the drill. Common chip shapes include flake chips, tubular chips, needle chips, conical spiral chips, band chips, fan chips, powder chips and so on.
Solution to the problem of improper chip shape
1. The methods of increasing the feed rate, intermittent feed, grinding the chisel edge, and installing chip breakers can be used separately or in combination to improve the effect of chip breaking and chip removal, and eliminate the problems caused by chips.
2. Vertical machining center can use professional chip breaker drill to make holes. For example: adding a designed chip breaker in the groove of the drill bit will break the chips into more easily cleaned chips. Debris is smoothly removed along the groove and will not block in the groove. Therefore, the new chipbreaker drill has a much smoother cutting effect than the traditional drill bit.
Drilling accuracy
The accuracy of the hole is mainly composed of factors such as aperture size, position accuracy, coaxiality, roundness, surface roughness, and hole burrs.
Factors that affect the accuracy of the processed hole during drilling:
1. The clamping accuracy and cutting conditions of the drill, such as tool holder, cutting speed, feed rate, cutting fluid, etc.;
2. The size and shape of the drill bit, such as the length of the drill bit, the shape of the blade, the shape of the drill core, etc.;
3. Workpiece shape, such as orifice side shape, orifice shape, thickness, clamping state, etc.
Drilling is the basic process of a vertical machining center. Maintaining high speed and efficiency while ensuring accuracy is our basic requirement for drilling.
