Application of Anti-Vibration Fine Boring Tools in Automotive Steering Knuckle Machining - BIG DAISHOWA
Application of BIG Anti-Vibration Fine Boring Tool in Automotive Steering Knuckle Machining
● Machined Product: Automotive Steering Knuckle
The automotive steering knuckle is an important component in the vehicle steering system. The steering knuckle's kingpin hole is assembled together with the kingpin, front axle, etc., effectively transmitting the steering angle from the steering wheel to the front wheels, controlling the vehicle's path during operation, thereby ensuring safe and accurate vehicle movement. The steering knuckle is subjected to complex forces, including variable bending stress from changing loads, as well as certain impact loads and torsional moments. Its geometric shape is relatively complex, with high positional accuracy requirements between various geometric surfaces. The level of precision directly affects the steering accuracy during vehicle operation.
● Machining Challenges
- The entire kingpin hole of the steering knuckle is relatively deep, making it difficult to machine in a single pass.
- The roundness requirement for the upper and lower lug holes of the kingpin hole is within 0.005mm.
- The coaxiality requirement for the upper and lower lug holes is within 0.012mm.
- Hole surface roughness: Ra1.6.
● Previous Machining Methods
Method 1:
Using the rotary table to flip the part, machining the upper and lower lug holes of the kingpin hole in two separate operations.
Problem: Relies on the accuracy of the rotary table and fixturing, making it difficult to guarantee the precision required for kingpin hole machining.
Method 2:
Using a reamer to directly ream through the kingpin hole.
Problem: There are many models and types of steering knuckles, requiring a large number of corresponding reamers, resulting in high tooling costs.
● BIG Machining Solution
Using an anti-vibration fine boring tool to machine the entire kingpin hole (both upper and lower lug holes) in a single operation.
Advantage 1:
Directly boring through the kingpin hole in one pass not only reduces dependence on the rotary table and fixture accuracy but also provides more guaranteed precision. It also reduces waste of non-machining time, improving efficiency.
Advantage 2:
Compared to reamers, boring tools have adjustable sizes, a wide machining range, and can accommodate various specifications and sizes, reducing the number of tools required and lowering the customer's overall costs.
● Machining Example & Conclusion
Machining Requirements:
Tooling Solution:
Basic Shank: BT50-CKB3-124
Anti-Vibration Fine Boring Head: CKB3-EWN32DP-160
Insert: TPGP080204L AC520U
(Overhang: 284mm, L/D Length-to-Diameter Ratio reaches 9 times)
Cutting Parameters:
Machining Result:
Actual Machined Size: Ø37.971mm
Surface Roughness: Ra=1.6
Roundness and coaxiality both met requirements.