Deep Hole Processing of Piston Pin

deep hole processing

Deep Hole Processing of Piston Pin

Deep Hole Processing Background

Deep hole processing of piston pin is according to client’s requirements as follwoing:
Must be efficient to meet high productivity and be stable to meet high precision requirment.
Besides, client also requires no visible scratches on hole surface.
Accordingly, we decide to introduce 4-spindle deep hole drilling machine
After studying of workpiece, our engineering team confirm to use manipulator and conveyor to consist of auto-loading system. 
Above all, ensures efficiency and accuracy.


Simultaneously processing 4 PCS of workpiece. The efficiency is secured.

The hole diameter tolerance is  ± 0.05 mm, and roughness is 0.8 um without visible scratches.

So, completely satisfy processing requirement. 

Specific Requirement

Workpiece: piston pin
Material: 20#; 20 Cr
Inner hole diameter range: Φ20、Φ22、Φ23
Drilling depth range:100 mm
Production Demand: batch production; high requirement of inner hole surface roughness, no visible scratches
Tolerance: ±0.1 mm

hole drilling

Option of Deep Hole drilling Machine

At the beginning,  we know model ZK2125*4/500 is the right machine. 

And for convenient on-site management, saving cost of human power and increasing processing efficiency, introduced auto-loading system. Then the final model is ZK2125*4C/500. (letter C stands for lateral transmission of loading conveyor) .

The model can also be designed as 6-spindle one.

Use hydraulic collet clamping. Because the verticality between workpiece’s end and outside cycle cannot be guaranteed for the preceding process is sawing. Additionally, before drilling, the workpiece’s chamfer isn’t processed. Thus, use hydraulic collet clamping to ensure the axiality.

Gun drilling tool is insert coated gun drill by BOTEK. Which can conveniently replace inserts and easily break steel chip. 

deep hole processing

Machine Overview

The machine bed is HT300 one-piece cast with high rigidity. 

For oil coolant and filter system, we adopt the gear pump group and variablr frequency motor, so that oil pressure and flux is adjustable. 

Meanwhile, to secure the performance of the machine, equipped with multiple filter and oil temperature control devices. 

Transmission & Processing

 The working procedure is as belowing. 

  1. Chain conveyor transmits raw material to front of the machine.

  2. Transmission manipulators grab, lift and place 4 PCS workpiece onto the servo conveyor. 

  3. Servo conveyor transmits workpiece to processing area right below 4 PCS of spindles. 

  4. Manipulators of working area grab 4 PCS of workpiece and insert them into hydraulic collet.

  5. Drilling begins when clamping is finished. 

  6. Manipulators of working area grab finished and place onto the conveyor to transmit them to the finished conveyor to conclude the processing circle. 

deep hole processing

deep hole processing

Processing Parameter

Rotation speed of drilling spindle: 1400 rpm

Feeding speed:140 mm/min

Processing Time:88 s/4 PCS of workpiece

Roughness:0.8 um

Diameter: Φ23.05

Completely satisfied the requirements of part processing.