Cylindrical Turning and Face Turning - Course: Techniques for Machining of Material. Instruction Examples for Practical Vocational Training: Instruction example 2.1.: Pressure disk

Cylindrical Turning and Face Turning - Course: Techniques for Machining of Material. Instruction Examples for Practical Vocational Training

		(introduction...)
		Preface
		Instruction example 2.1.: Pressure disk
		Instruction example 2.2.: Flange
		Instruction example 2.3.: Bearing shaft
		Instruction example 2.4.: Connection piece

Instruction example 2.1.: Pressure disk

This example serves to practise turning of simple cylindrical parts held in a chuck without counter-support.

Figure

Material

St 60 (St = steel, 60 = tensile strength 600 MPa)

Dimensions

(blank)
dia. 70 × 25 (dia. 70 = diameter 70 mm 25 = length in mm)

Cutting and operating tools

Right-offset side-cutting tool, key, right-bent roughing tool

Measuring and testing tools

Vernier caliper, depth gauge

Auxiliaries

Supporting plate (for turning tools), chuck jaws

Required previous knowledge

Reading of drawings, geometry of angles of cutting tools, types and application of clamping tools, measuring and testing.

Sequence of operations	Remarks
1. Measuring of blank	Undersize is not acceptable. Arrange sequence of operations accordingly or separate undersize blanks, respectively.
2. Clamping of workpiece	Type of clamping: "chucking" in stepped chuck jaws which can be turned out. Clamp short.
3. Clamping of tool	Central position to axis of rotation is absolutely necessary. Nose grinding angle 1 × 45° is favourable to tool life and guarantees "deburring" operation.
4. Setting of cutting values	In case of infinitely variable speed gear pay attention to cutting speed constant.
5. First cut on circumferential surface	Switch on lathe. Set bed stop (to avoid accidents). Let turning tool take first cut on the circumferential surface of the rotating part. Set scale of cross slide to "0" (for adjustments consider lost motion of spindle). Return tool carrier to initial position. Set depth of cut.
6. Turning of dia. 65	Switch on longitudinal feed. Cut until total length is reached. Watch formation of chips. For short-chip material use safety goggles. Switch off feed. Carry out dimensional and visual inspection.
7. Facing - right-hand face	Take first cut on end face. Lock tool slide in longitudinal direction. Return tool carrier to initial position. Set depth of cut. Switch on feed (visual inspection to make sure face is machined all over and clean). Switch off feed.
8. Deburring	Utilize chamfer 1 × 45° Use top slide.
9. Re-chucking	Re-chuck part by 180° around its longitudinal axis. Pay attention to any radial or axial run-out.
10. Clamping of tool	Make sure it is in central position.
11. Turning - total length 20 mm	Set bed stop. Take first cut on end face. Set scale of cross slide to "0". Return tool carrier to initial position. Set depth of cut. Switch on cross feed. Pay attention to surface finish. Ensure correct centre.
12. Deburring	Adjust top slide. Use side-cutting edge.
13. Unload workpiece
14. Final inspection	Dimensional and visual inspection.

For workpiece batches, the sequence of operations is to be repeated up to operation 08 and to be continued from operation 09 at the end of the batch.

Figure