How to Process Steel Rods into Twist Drill Bits?

This is a professional article about the production process of twist drill bits. If you can read it patiently, I believe you will gain a lot.

In the last article, we explained the concept of twist drill bits to you. This article will tell you how to produce a qualified twist drill bit. To put it simply, it has a total of 12 steps, namely incoming material, drawing with incoming material, cutting off material, chamfering, heat treatment, rough grinding of outer circle, flat head chamfering, groove grinding, edge cleaning, opening, double rear angle, and fine finishing. After the 12-step process of grinding the outer circle, we will also conduct a full inspection, engraving, cleaning and packaging of the drill bit. The packaged drill bits will be shipped to customers as quickly as possible.

What follows is a detailed explanation of each step of the production process:

1. Incoming materials and wire drawing. The factory will temper the raw material of the drill bit. The tempering time is usually more than 24 hours. The tempered raw material will then be placed on the drawing equipment. After being repeatedly stretched and polished by the mold inside the equipment, it will be wound and the outer diameter of the raw material will be reduced. Once the processing is within the process requirements, the error control in this step will be very strict, and a certain outer diameter margin will often be left.

2. Cutting off materials and tipping. After drawing the incoming materials, the factory will use cutting equipment to cut the raw materials to a fixed length. This step often leaves a 3 mm margin for the length of the cut materials. The purpose is to prevent the wear and tear of the subsequent processes from being insufficient. The next step in cutting off the material is to tip it. This step will make it shorter to a certain extent. In the chamfering process, we will use chamfering equipment to carve an angle on one end of the blank to create a sharp corner. The chamfering requirement cannot be smaller than the opening angle to ensure the concentricity of the later processed products.

3. Heat treatment. After completing the above four steps, the factory will heat treat the material and improve its strength and formability through four times of tempering.

4. Roughly grind the outer circle. The grinding wheel in the cylindrical grinding equipment is used for rotational grinding to remove the oxide scale produced after heat treatment, and the outer diameter of the drill bit is ground to within the range of process requirements.

5. Flat head chamfering and groove grinding. The purpose of the flat head chamfering process is to make the tail end of the drill bit conform to the standards for the installation of the drilling rig. The next step is groove grinding. In this step, the factory will use groove grinding equipment to rotate and groove the blank. The groove grinding process requires good control of the length, depth and surface finish of the groove. When the grinding wheel is severely worn, it needs to be replaced, because the wear of the grinding wheel will affect the dimensional accuracy of the grinding groove.

6. The ninth step is the edge cleaning process. The factory will use automatic edge cleaning equipment to polish the spiral outer wall of the drill bit. In this step of the process, it is necessary to pay attention to the consistent leaf width, consistent ligament depth and consistent outer diameter after edge cleaning.

7. After completing the edge cleaning, we need to open the material. Through fully automatic opening equipment, the head of the material is processed according to the process standard requirements. This process requires the surface of the cutting edge to be smooth, the size of both sides of the opening to be consistent, and there to be no chamfers, scorch spots, etc. With the completion of this step, the prototype of a drill bit has been formed.

8. Step 11 is the double back corners. Through the automatic back corner chamfering equipment, two back corners are cut on the head according to the requirements. We have strict inspection requirements for this step. The two back corners are required to be symmetrical and consistent in length. The knife edge cannot be broken and must be in the same position. On the parallel line, this step greatly affects the sharpness of the drill bit and the efficiency of the drill bit.

9. Precision grinding the outer circle. This step is similar to rough grinding of the outer circle, except that this step is fine grinding, which is a final step to form a qualified drill bit. The surface of the product is finely ground using the grinding wheel in the grinder equipment to within the standard range of size requirements. This step requires ensuring the smoothness of the product surface, the concentricity of the drill bit, and ensuring accuracy.

After completing the above process steps, a twist drill bit has been produced. But it is not enough. In order to ensure the qualification rate of the product, we will arrange specialized personnel to conduct a comprehensive inspection. The inspection requirements are that there should be no obvious difference in the length of the drill bit, there should be no gaps in the cutting edge, and there should be no black spots or obvious processing lines on the surface of the drill bit, etc.

After completing the drill bit inspection, we use a rolling engraving machine to roll and engrave one end of the drill bit clamping handle for qualified drill bits. On the one hand, the basic attributes of the drill bit will be imprinted, and on the other hand, the LOGO required by the customer will be imprinted. We will ensure that the engraving is clear, the depth of the engraving is consistent, the information is complete, and the font direction is correct and consistent.

Finally, we clean and package the finished drill bits. Clean the impurities and stains attached to the drill bit during processing to ensure that the surface of the drill bit is clean and free of water stains. After cleaning, drying is carried out, and then we will pack, label and carton according to customer requirements to ensure the number of boxes, the accuracy of the mark information, the accuracy of the weight of the whole box, etc.

After completing all the above steps, we will dispatch our high-quality and qualified twist drill bits to our dear customers as scheduled. If you want to ask more professional questions about twist drill bits, you can come to our FORUM to comment, and our professionals will give you a timely and professional reply.