What are Machining Parts: Types, Benefit and Design Guide?

Introduction: What are Machining Parts?

Machining parts are products obtained from various machining processes like turning, milling, drilling, and grinding. As per the Machining Parts Manufacturer, they consist of material taken from raw plastic, metal, or composite workpieces to obtain the required shape, size, and surface finish. Machining parts are significant products in industries like the automobile, aerospace, electronics, construction, and medical equipment industries, among numerous others.

Whatever it is, a precision gear, an engine part, or a specific bracket, machining prevails in manufacturing today because of unmatched precision and customization.

Types of Machining Parts

There are quite numerous machining parts, which are categorized based on the process of manufacturing, material, and application. They are the most utilized types, explained below:

1. Turned Parts

Lathe is used to make turned parts, which are generally axisymmetrical. Turned parts consist of bushings, pins, rods, and shafts. The part is cut by the elimination of material from the part while the work is being turned by the action of a cutting tool.

2. Milling Parts

Parts are manufactured on milling machines, which move along a sequence of axes in cutting away material from a fixed workpiece to produce milled pieces. Plates, brackets, and more complex shapes are milled.

3. Drilled Parts

Drilled parts are those parts that require cylindrical holes for wiring, mechanical, or fastening purposes. Drilling is occasionally independent but also done with turning or milling.

4. Ground Parts

Grinding is employed where ultra-fine surface finish and tolerances are specified. Ground components are generally employed on high-performance machine elements such as gearboxes or engines.

5. EDM (Electrical Discharge Machined) Components

Employed in products with extremely complex geometry or extremely hard material, EDM-machined components are fashioned by material removal in a controlled manner by electrical sparks.

6. Threaded Parts

Threaded components like threaded inserts, screws, and bolts are usually manufactured through thread rolling or thread cutting and are integral components of assembly-based products.

7. Special Parts

They comprise precisely machined parts that are made to specific design standards. They are mostly utilized in the instrumentation, robot, and aerospace applications.

Advantages of Machined Parts

Machining is the most versatile of all processes because it can perform precision, flexibility, and repeatability. The key advantages are described below:

1. High Precision and Accuracy

Machined parts may then be produced with tolerances as small as ±0.001 mm. This degree of precision is employed mainly in aerospace, defence, and medical device manufacturing.

2. Surface Finish Quality

Machining can create parts with extremely high surface finish, sometimes even eliminating secondary finishing processes.

3. Material Versatility

Machining is very versatile, with the capability to machine a wide range of materials like metals (steel, aluminium, brass, and titanium), plastics (nylon, PEEK, and Delrin), and composites. This makes machining valuable in nearly every industry.

4. Flexibility and Customization

Unlike moulding or casting, machining can produce one-off or small quantities at low cost. This is ideal for tooling, one-offs, and prototypes.

5. Less Scrap with CNC

New Computer Numerical Control (CNC) machines minimize wastage and maximize tool path, and thus production is better overall.

6. Economies of Scale and Repeatability

After a digital design file is created, the part can be duplicated time and again with minimal deviation in attempting to achieve consistency from run of mass production to run of mass production.

7. Quick Turnaround

Lead times are considerably minimized through CNC technology. Quick change and quick prototyping without the necessity of having to retool.

Design Manual for Machining Parts

Machining design does address issues of cost, performance, manufacturability, and function. Proper procedures in machining parts design in stages are presented below.

1. Material Selection

Select a material based on what you require in your application—machinability, corrosion resistance, strength, weight, or thermal conductivity.

●       Aluminum is corrosion resistant, light, and machinable.

●       More corrosion resistant and stronger but less machinable.

●       Parts of low stress and low weight may be produced from plastic like Delrin or PEEK.

2. Fits and Tolerances

Specify critical dimensions and tolerances. Apply tight tolerance on detail only when unavoidable. Tight tolerances are time-consuming and expensive.

●       For general characteristics, apply general tolerances (e.g., ±0.1 mm).

●       On mating parts, remember various types of fits—clearance, interference, and transition fits.

3. Limit Advanced Features

Steer clear of highly engineered and complicated geometries with numerous setups or special features that call for special fixtures. Use simple features—flat, regular surfaces, routine holes, and radii—to minimize machining cycle time and expense.

4. Standardize and Regularize the Hole Sizes

Use standard and normal drill sizes for holes in the design to avoid specialty tooling. Consider thread depth and tapping clearance when designing tapped holes.

5. Avoid Abrasive Internal Corners

Internal angles should be filleted and not sharp since most of the milling cutters are cylindrical in shape. Sharp internal angles require additional machining operations or EDM.

6. Provide Sufficient Wall Thickness

Thin walls will flex and vibrate when cutting. Provide sufficient wall thickness (usually >1.5 mm in metals) to enable easy construction and stiffness.

7. Check for Tool Accessibility

Check part geometry for tool accessibility. Undercuts, close slots, or deep pockets are hard to machine and need special care using special tools or 5-axis machines.

8. Allow Fixturing

Design it so that the part is to be supported during the process of machining. Flat surfaces or features for clamp or fixturing points are accurate. at reduced cost.

 General Applications for Machined Parts

Machined parts exist in nearly every major industry:

●       Aerospace: Turbine parts, structural brackets, and enclosures.

●       Automotive: Engine blocks, suspension arms, and specialty items.

●       Medical Devices: Implants, surgical instruments, and enclosures.

●       Electronics: Heat sinks, connectors, and enclosures.

●       Industrial Equipment: Gearboxes, manifolds, and precision gears.

Conclusion

Machined parts are the cornerstone of modern engineering and manufacturing. They are strong, flexible, and accurate, and hence they are a fundamental component in most sectors. As a product designer, design engineer, or producer, you should be familiar with machining part types, advantages, and design key factors in developing successful, functional, and cost-effective parts. Design for manufacturability, the efficient use of the CNC technology and choice of material can enable you to develop your machined parts as robust in terms of reliability and performance.

Also Read: Precision Sheet Metal Fabrication: From Design to Finished Product