As a core device in the metal - processing field, universal grinding machines serve the precision manufacturing industry extensively due to their multifunctionality and high - precision characteristics. This article will systematically analyze the technical features and usage value of this key processing tool from four dimensions: the device types, operation essentials, working principles, and industry applications.
I. Core Types and Technical Features of Universal Grinding Machines
Based on the differences in processing objects and techniques, universal grinding machines can be divided into four technical branches:
1. Cylindrical Grinding Machines
- Basic Function: Specializes in the precision grinding of cylindrical and conical outer surfaces and can handle the shaft - shoulder end faces simultaneously.
- Technical Upgrade: Some models are equipped with an internal grinding module, supporting the processing of internal holes and large - taper inner and outer surfaces.
2. Surface Grinding Machines
- Processing Mode: Achieves workpiece surface processing through the peripheral or end - face grinding of the grinding wheel.
- Sub - types:
- Horizontal - spindle rectangular - table type: Suitable for high - precision surface processing, with the grinding wheel making intermittent transverse feeds.
- Vertical - spindle circular - table type: The end face of the grinding wheel performs high - speed grinding, supporting continuous production and increasing efficiency by over 30%.
- Specialized models: Include guide - rail grinding machines and double - end face grinding machines, meeting the mass - processing requirements of bearing rings, piston rings, etc.
3. Tool Grinding Machines
- Core Purpose: Aims at tool manufacturing and re - grinding, covering the processing of cutting tools such as drills, broaches, and milling cutters.
- Technical Evolution: CNC models can achieve complex - curve grinding with an accuracy of ±0.002mm.
4. Centerless Grinding Machines
- Process Feature: The workpiece is automatically positioned by the driving of the guide wheel without traditional clamping devices.
- Production Advantage: Suitable for the mass - processing of shaft - type parts, with the efficiency of a single machine 5 - 8 times higher than that of traditional models.
II. Key Operation Techniques and Process Control
The operation efficiency of universal grinding machines directly affects the processing quality. The following aspects need to be emphasized:
1. Grinding - wheel System Configuration
- Select the grinding - wheel grain size according to the material hardness. Diamond grinding wheels are recommended for cemented carbide.
- The dynamic - balance verification should be carried out every 80 hours to prevent surface ripples caused by vibration.
2. Workpiece Clamping Optimization
- The electromagnetic chuck workbench needs to be demagnetized regularly to avoid the influence of iron - chip residues on positioning accuracy.
- Special fixtures should be used for complex workpieces, and the clamping error should be controlled within 0.01mm.
3. Grinding Parameter Setting
- Rough - grinding stage: Keep the linear speed at 35 - 45m/s and the feed rate at 0.02 - 0.05mm/stroke.
- Fine - grinding stage: Reduce the speed to 20 - 25m/s and use a micro - feed of 0.005 - 0.01mm to ensure a surface accuracy of Ra0.4μm.
III. Analysis of Core Working Principles
Universal grinding machines achieve complex processing through multi - axis linkage. The typical working modes include:
1. Cylindrical Grinding Mode
- Main motion: The grinding wheel rotates at a high speed (usually 1800 - 3600rpm).
- Feed system: The compound motion of the workpiece rotation (circumferential feed) and longitudinal movement (axial feed).
2. Tapered - surface Processing Solution
- Long tapered surface: Adjust the inclination angle of the workbench (within ±30°) to keep the axis of the grinding wheel non - parallel to that of the workpiece.
- Short tapered surface: Use plunge - grinding, with the grinding wheel making continuous transverse feeds, reducing the processing time by 40%.
3. Internal - hole Grinding Technology
- High - speed spindle: The rotational speed of the internal grinding wheel reaches 10000 - 20000rpm, supporting a micro - lubrication system.
- Online measurement: Equipped with an aperture - monitoring probe to provide real - time feedback on dimensional errors.
IV. Panorama of Industry Applications
The precision - processing ability of universal grinding machines enables them to play a key role in multiple strategic industries:
1. Transportation Field
- Automobile manufacturing: Finish - processing of core components such as engine crankshafts and transmission gears.
- Rail transit: Plane grinding of wheel - set bearings and brake discs.
2. Equipment Manufacturing Sector
- Machine - tool industry: Processing of precision mating surfaces of guide - rail sliders and spindle components.
- Energy equipment: Treatment of turbine - blade profiles and nuclear - power valve sealing surfaces.
3. Precision - Parts Field
- Electronic communication: End - face grinding of optical - fiber connectors, with a surface - roughness requirement of Ra0.1μm.
- Medical devices: Precision forming of artificial - joint spherical surfaces and surgical - instrument cutting edges.
4. Tool - Manufacturing System
- Cemented - carbide cutting tools: Edge - blunting treatment, increasing the service life by over 200%.
- Mold processing: Precision trimming of injection - mold parting surfaces and die - casting - mold cavities.
With the development of intelligent manufacturing technology, universal grinding machines are evolving towards numerical control and compounding. New - generation models integrate online detection and adaptive compensation systems, maintaining the processing accuracy at a stable micron - level, and continuously promoting technological innovation in the precision manufacturing industry.
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