Discipline "cutting tool" theme "metal cutting tool"

Contents

Introduction

1. Analysis of source data

2. Development of turning assembly cutter

2.1  Tool Selection

2.2  Calculation of cutting modes, cutting forces, cutting power

2.2.1 Selection of processing stages

2.2.2 Selection of cutting depth

2.2.3 Supply Selection

2.2.4 Selection of cutting speed

2.2.5 Calculation of cutting forces

2.2.6 Calculation of cutting power

2.3 Calculation of the cutter for strength

2.4  Calculation of basic machine time

2.5  Selection of Alternative Tool Options

3. Development of prefabricated drill

3.1 Tool Selection

3.2 Calculation of cutting modes, cutting forces, cutting power

3.2.1 Select Cutting Depth

3.2.2 Feed Selection

3.2.3 Selection of cutting speed

3.2.4 Calculation of cutting forces

3.2.5 Calculation of cutting power

3.3 Calculation of basic machine time

3.4 Selection of alternative tool options

4. Development of boring cutter

4.1  Tool Selection

4.2  Calculation of cutting modes, cutting forces, cutting power

4.2.1  Selection of processing steps

4.2.2  Select Cutting Depth

4.2.3  Supply Selection

4.2.4  Selection of cutting speed

4.2.5  Calculation of cutting forces

4.2.6  Calculation of cutting power

4.3 Calculation of the cutter for stiffness

4.4 Calculation of basic machine time

4.5 Selecting Alternative Tool Options

5. Worm Mill Development

5.1 Tool selection.                                                                                    

5.2 Design Calculation

5.3 Calculation of cutting modes, cutting forces, cutting power

5.3.1 Select Cutting Depth

5.3.2 Supply Selection

5.3.3 Selection of cutting speed

5.3.4 Calculation of cutting power

5.4 Determination of the main machine time

6. Development of keying

6.1 Tool Selection

6.2 Design Calculation

6.3 Calculation of cutting modes, cutting forces, cutting power

6.3.1 Selection of cutting speed

6.3.2 Calculation of cutting forces

6.3.3 Calculation of cutting power

6.4 Calculation of basic machine time

Conclusion

Appendix A Bibliographic list

Project Description

PASS CUTTER, BORING CUTTER, PREFABRICATED DRILL, WORM CUTTER, KEYWAY.

The object of work is the practical mastery of the knowledge gained during the study of the discipline "Cutting Tool."

This work contains all the necessary calculations for the design:

- turning assembly cutter for treatment of the main external surfaces of the gear wheel;

- prefabricated drill to obtain the gear wheel mounting hole;

- boring assembly cutter for treatment of landing hole;

- worm cutter for production of toothed rim;

- keying to obtain the keying slot.

Introduction

The development of tool production is one of the most important tasks of the development of mechanical engineering.

The quality, operability and reliability of the cutting tools greatly depends on the accuracy of the workpiece, the performance and efficiency of the processing process, especially in automated manufacturing.

When designing cutting tools, knowledge of the theoretical foundations of tool design and calculation is required.

The cutting tool should provide the required shape, dimensions and quality of the workpiece, the highest efficiency of the processing process with the lowest costs, be technological in manufacturing, have the ability to restore cutting properties during operation, while striving to minimize the consumption of expensive tool materials.

During design it is necessary to ensure all requirements for the tool:

- operability;

- quality of work;

- performance;

- processability;

- economic efficiency.

The design result is a design document in the form of a drawing or electronic model that contains all the necessary information for manufacturing and controlling the tool.

Development of turning assembly cutter

A cutter is a single-cut tool for processing parts using translational or rotational motion and the ability to be fed in any direction. In this course design, a part is made - a gear wheel made of structural alloyed steel of grade 40X GOST 454371. Machining of the external surfaces of the part is performed with a turning cutter.

2.1 Selection of tool.

The height of the cutter used on the machine 16GS25F3 does not exceed 25 mm, the holder with a section of 20x20 mm is accepted.

According to Annexes 1, 5 [1] and based on the processing conditions, the rhombic shape of the plate CNMG120408 according to GOST 2424980 from solid alloy T5K10 GOST 388274 is accepted - for rough and semi-finished treatment stages with a plate thickness of 4.76 mm. Shank material - steel 45 GOST 105088. This choice of tool material provides sufficient wear resistance, strength, hardness, and rather high productivity at relatively low cost.

According to Annex 6 [1], the method of securing the plate by means of a central screw for the rough and semi-finished processing stages is selected.

According to Annex 7 [1] and based on the processing conditions, the main angle in the plan is chosen to be 95 °.

Annex 8 [1] defines the remaining geometric parameters of the cutting part.

For the rough and semi-finished treatment stages:

- rear angle α = 8 °;

- front angle γ = 12 °;

- chamfer width of the main cutting edge f = 0.4 mm;

- radius of rounding off of the cutting edge ρ = 0.025 mm;

is the radius of the tip of the cutter r = 1 mm.

The normal durability period is as per Appendix 13 [1] Tn = 30 min.

Design and dimensions of SCLCR2020K12 lathe cutter with attachment of replaceable plates by screw through hole is accepted as per GOST 2499681.

2.2 Calculation of cutting modes, cutting forces, cutting power.

2.2.1 Selection of processing stages.

According to the map 1, the sheet 3 [1] determines the necessary processing stages for obtaining the dimensions of the part corresponding to the 12th quota, from the blank of the 16th quota it is necessary to carry out processing in two stages: draft, semi-pure.

2.2.2 Selection of cutting depth.

Map 2 [1] defines the minimum required cutting depth for the semi-finished treatment stage.

In the semi-finished treatment stage: for the outer surface of the workpiece, the diameter of which corresponds to the size interval 180... 250 mm, it is recommended t = 2.20 mm (pos. No. 4, ind. "a").

The cutting depth for the rough treatment stage is determined based on the total processing allowance and the cutting depth at the semi-finished treatment stage: t = 4.30 mm.

Development of prefabricated drill

Drill is a cutting tool for processing holes in solid material, or for drilling holes in two simultaneous movements: rotation of drill around its axis and translation of feed along tool axis. In this course design, the assembly drill produces a landing hole in steel of grade 40X GOST 454371.

Development of boring cutter

A cutter is a single-cut tool for processing parts using translational or rotational motion and the ability to be fed in any direction. In this course design, a part is made - a gear wheel made of structural alloyed steel of grade 40X GOST 454371. The boring cutter performs treatment of the landing hole.

4.1 Tool selection.

Cutters (mandrels) shall be used with the smallest technologically possible length and the largest technologically permissible section with a section diameter of d = 25 mm.

In accordance with the recommendations of Annex 1 [1], the treatment is carried out with hard alloy plates T15K6 GOST 388274 at the finishing and finishing stage. Shank material - steel 45 GOST 105088. This choice of tool material provides sufficient wear resistance, strength, hardness, and rather high productivity at relatively low cost.

According to Annex 5 [1] and based on the processing conditions, the square shape of the plate with the rear angle and chip-breaking grooves SCUM120408 according to GOST 2425280 is accepted.

According to Annex 7 [1] and based on the conditions of processing, the main angle in the plan-view [TAG] = 75 ° and the auxiliary angle in the plan-view [TAG] 1 = 15 ° are selected.

Annex 8 [1] defines the remaining geometric parameters of the cutting part.

For the rough and semi-finished treatment stages:

- rear angle α = 7 °;

- front angle γ = 10 °;

- radius of rounding off of the cutting edge ρ = 0, 25 mm;

is the radius of the tip of the cutter r = 0.8 mm.

The normal durability period is as per Appendix 13 [1] Tn = 45 min.

Boring cutter S25RCSKCR12A is accepted with attachment of replaceable plates with tack on top as per GOST 2661285.

4.2 Calculation of cutting modes, cutting forces, cutting power.

4.2.1 Selection of processing steps.

According to the map 1, the sheet 2 [1] determines the necessary processing stages to obtain the dimensions of the part corresponding to the 7th quota. From the procurement of the 16th quota, it is necessary to conduct processing in three stages: draft - obtaining the 14th quota, semi-pure - the 12th quota, finishing - the 7th quota.

Worm Mill Development

Tooth cutting is the most common and most labor-intensive in the production of gears.

The performance and precision of the toothing treatment is higher than that of the toothing, so a worm cutter is selected to obtain a toothed rim.

The method of cutting teeth with a worm mill is economical.

The worm cutter is a single or multi-start worm that has a defined initial contour of the rack, and the longitudinal chip grooves located along the axis form teeth with cutting edges necessary for cutting processing. The teeth of the cutter are naked.

In this course design, the worm mill produces a toothed rim of a cylindrical spur wheel made of steel grade 40X GOST 454371.

Worm cutters are designed for cutting cylindrical wheels with straight and oblique teeth, worm wheels and splined shafts.

Select a tool.

We accept a worm modular milling mill made of high-speed steel P6M5 GOST 1926573. To obtain a wheel of 7 degree of accuracy according to GOST 164381, we select a single-start finishing worm mill of type 1, accuracy class - AA according to GOST 932480.

The main structural and design dimensions are accepted according to GOST 932480 :

external diameter dao = 90 mm, mounting hole diameter d = 40 mm, shoulder diameter d1 = 60 mm, cutter length L = 90 mm, shoulder width l = 5 mm (therefore, working length of cutter 100 mm), number of teeth (number of chip grooves) z0 = 14; front angle γ = 0 °; rear angle α = 12 °.

Development of keying

The rails are a complex, expensive tool and should be designed to provide as long a service life as possible, which is particularly dependent on the correct selection of tool material for the working parts of the rails.

To pull key grooves in cylindrical holes, two types of draws are used: with a flat body and with a cylindrical body. Links with flat thickened body have shape of strip with rectangular section. They move during operation in rectangular slot of guide mandrel. The rear cylindrical end of this mandrel is inserted into the opening of the transition ring, which in turn is connected to the table or chuck of the extension machine. A workpiece is put on the front end of the mandrel, inside the hole of which a key groove must be cut. Intermediate cylindrical collar-flange is support part of mandrel.

In this course design, by pulling the keyway, a keyway is obtained in a previously processed landing hole.

6.1 Tool selection.

The material of the cutting part of the pulling is steel P6AM5 GOST 1926573; shank material - steel 45X GOST 454371. Pulling with welded shank. Pulling with flat thickened body as per GOST 1821790 and type 1 shank as per GOST 404370 is accepted.

Conclusion

During the course project, knowledge of the Cutting Tool course is consolidated, the ability to use information from previously studied disciplines for practical applications is developed, gaining skills in working with reference literature, state and industry standards.

In this project, a prefabricated (pass cutter, boring cutter, drill) and profile (worm cutter, keyway) tools were developed.

When developing a metal cutting tool, they learned to choose a tool with the necessary parameters, to select alternative versions of European and Asian manufacturers. During the course project, such important information from the course as strength calculations, rigidity of the dimensional tool, verification calculations of the profile tool, and the selection of the material of the blade and fastening parts found practical application.

Thus, course design in the discipline "Cutting Tool" is an important stage of training.