1. Drawing Analysis

Main dimensions and tolerances:

Outer circle: ϕ62mm，ϕ35mm h6,ϕ34mm h6
Inner hole: ϕ20mm, keyway（6mm）
Length: 34mm.
Hole: 6 ϕ7mm through holes
Geometric tolerance：
The radial runout of the outer circle of ϕ 35mmh6 relative to the reference A (ϕ 20mmH7 inner hole axis) is 0.02mm.
The radial runout of the outer circle of ϕ 34mmh6 relative to reference A is 0.02mm.
The perpendicularity of the right end surface to reference A is 0.02mm.
Surface roughness:
(ϕ35mm h6,ϕ34mm h6)The roughness requirement is Ra0.8, which requires grinding or precision turning.

The remaining machining surfaces are Ra1.6 or Ra3.2.

Unspecified chamfer 1X 45°.

2. Machining technology route

Raw material selection: ϕ 65 × 40 mm bar material

Process 10: Material cutting

Sawing machine cutting size ϕ 65 × 40 mm.

Process 20: Heat treatment (preparation)

Normalizing or tempering treatment, hardness 220-250 HBS, improves cutting performance.

Process 30: Rough turning (clamp one end, turn the other end)
1. The three jaw chuck holds the outer circle of the blank.

2. The turned end face shall be flat.

3. Rough turning of outer circle outer circle ϕ 63, ϕ 35, ϕ 36, leaving a margin of about 1-1.5mm.

4. Drill a hole of ϕ 18 and drill a rough hole to ϕ 19.5mm.

Process 40: Rough turning (turning the other end)

Turn around and clamp the outer circle of ϕ 63.

Turn the end face to ensure a total length margin.

Rough turning the outer circle and step on the other end.

Process 50: Semi precision turning (key process, ensuring the basic tolerance of form and position)

Clamping method: Soft claw clamping ϕ 62 outer circle

1. Precision turning of the end face.

2. Precision turning of inner hole ϕ 20H7 (leaving grinding or reaming allowance, such as turning to ϕ 19.8).

3. Precision turning of outer circles ϕ 35h6, ϕ 34h6, ϕ 62 (leaving grinding allowance, such as 0.3-0.4mm).

4. Turning groove 3 × 0.5 (left and right sides).

5. Chamfering 1 × 45 °.

Process 60: Drilling 

Positioning of inner bore20H7 and outer end face.

Drill 6 -7 holes.

Deburring of burrs.

Process 70: broaching (keyway)

The inner hole keyway shall be broached to ensure the width and depth of 6mm.

Process 80: Grinding (guaranteed accuracy Ra0.8 and 0.02 runout)

Clamping: Insert with a high-precision mandrel (clearance fit or micro-expansion mandrel)

In hole 20H7 and keyway, top the centers at both ends or both ends of clamping mandrel. This ensures the runout of the outer circle to the hole.

Grindingφ 35h6 excircle

Grindingφ 34h6 excircle

Grind the right end face to ensure the perpendicularity of 0.02mm.

Process 90: Blackening

Process 100: Inspection

1. Use a micrometer to measure the outer diameter ϕ 35h6, ϕ 34h6.

2. Use an inside micrometer to measure the inner hole ϕ 20H7.

Detect the radial runout (≤ 0.02) of the outer circle against the hole on a deflectometer.

Check the perpendicularity of the end face.

Process 110: Surface Cleaning and Storage

Cleaning, rust prevention treatment, and storage.