Brand: BeHappy
Certification: Gs, Scoc, Iecee
Support Customization: Oem
Place Of Origin: China
Species: Twist Drill Bit
Application: Masonry Drilling, Metal Drilling, Wood Drilling
Surface Treatment: Plain, Black Oxide
Packaging: Plastoc case
Productivity: 1, 000, 000 Set/Year
Transportation: Ocean,Land,Air,Express
Place of Origin: China
Supply Ability: 1, 000, 000 Set/Year
Certificate: ISO
Port: Shanghai ,Ningbo,Yiwu
Payment Type: T/T,D/P,T/Ts
Incoterm: FOB,CIF,EXW,FCA,DDU,DDP
(1) Helix angle β The helix angle is the angle between the helix of the outermost circle on the helical groove of the Drill Bit and the axis of the drill bit after it is expanded into a straight line. Since the lead of each point on the helical groove is the same, the helix angle of the drill is different at different diameters. Increasing the helix angle increases the rake angle, which is beneficial to chip removal, but the rigidity of the drill decreases. The helix angle of a standard Twist Drill is 18° to 38°. For drills with smaller diameters, the helix angle should take a smaller value to ensure the rigidity of the drill.
(2) Rake angle γOm [Because the rake face of the twist drill is a helical face, the rake angle of each point on the main cutting edge is different. From the outer circle to the center, the rake angle gradually decreases. The rake angle at the tip of the knife is about 30°, and it is about -30° near the Chisel edge. The rake angle on the chisel edge is -50° to -60°.
(3) Relief angle αOm [The relief angle of the selected point on the main cutting edge of the twist drill is represented by the feed relief angle αOm in the column section at this point. The column profile is a straight line parallel to the axis of the drill bit through the selected point m of the main cutting edge, and the cylindrical surface formed by the rotation of the straight line around the axis of the drill bit. αOm also varies along the main cutting edge, and the closer to the center αOm is. The relief angle α at the outer circle of the twist drill is usually 8° to 10°, and the relief angle at the chisel edge is 20° to 25°. This can make up for the influence of the reduction of the actual working clearance angle of each point on the main cutting edge due to the axial feed movement of the drill bit, and can adapt to the change of the rake angle.
| Specification: | |
| Product Name | 100pcs Screwdriver Bit Nut Driver Set Magnetic Bit Holder Drill Bit Set |
| Package | plastic case |
| Material | High speed steel; High carbon steel |
| Size | According to the customer's request |
| MOQ | 1 set for sample testing |
| 2000 sets for mass production | |
| Delivery time | 15~45 days, according to order quantity |
| Application | Suitable for a variety of applications |
| Payment terms | T/T, D/P, L/C, Paypal, Western Union, ect. |
| Certificated | SGS, RoHS, CE |
| Unit price | Contact us to get latest price (Larger quantity, more discount ) |
Product Photo
Product Categories : Drill Bit > Twist Drill Bit
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