Vibratory polishing machines: efficient solutions for metal surface treatment

In the field of metal processing, the precision and efficiency of surface treatment directly affects product quality and production costs. Vibratory polishing machine

as a set of high efficiency, uniform, flexible polishing in one of the equipment, is becoming the hardware, electronics, automotive and other industries, the core 

processing tools. In this article, we will start from the technical principle, application advantages, metal polishing process and operation points, to provide you with

a comprehensive analysis of this surface treatment "tool".

First, what is a vibration polishing machine?

Vibratory polishing machine is a kind of automated equipment that generates high-frequency vibration of the grinding trough driven by vibration motor or eccentric block, 

so that the grinding medium (a mixture of abrasive,polishing agent and water) collides, rubs and rolls with the workpiece, thus realizing the deburring, descaling, 

chamfering, and polishing of the surface of the workpiece. Its core structure includes: 

1.Grinding trough: mostly U-shaped or round, made of wear-resistant materials (such as PU, rubber or stainless steel), accommodating the workpiece and grinding media; 

2.Vibration system: composed of vibration motor, spring components, through the adjustment of vibration frequency and amplitude control of the polishing intensity; 

3.Control system: supports the setting of parameters such as rotational speed, time, dosing amount, etc. to realize intelligent processing. 

Second, the core advantages of vibratory polishing machine 

1. Efficient and flexible processing

 ·Single processing hundreds to thousands of pieces of workpieces (such as small-sized hardware, electronic components), the efficiency of 5-10 times more than the manual polishing; 

 ·Non-rigid contact polishing, to avoid the risk of scratches, deformation of the traditional mechanical polishing, especially suitable for complex curved surfaces (such as curved surfaces, blind holes)       workpieces.

2. Uniformity and consistency

 ·Vibration field uniform distribution, to ensure that the workpiece surface of the same force in all areas, polishing accuracy of up to ± 0.01mm; 

 ·Batch processing yield stability, suitable for the surface roughness (Ra0.2-1.6μm) have strict requirements of precision parts.

3. Low-cost adaptability

 ·No need for professional and technical personnel, low threshold for operation, energy consumption is only 1/3 of the traditional polishing equipment; 

 ·Supports a variety of grinding media switching, can be adapted to copper, aluminum, stainless steel, titanium alloy and other metal materials, as well as plastics, 

  ceramics and other non-metallic materials.

Third, the working principle: the vibration field in the “micro-grinding” mechanism 

When the vibration polishing machine starts, the grinding trough to a specific frequency (50-300Hz) and amplitude (0.5-5mm) vibration, driving the media to form

a spiral trajectory: 

1. Media movement: abrasive (such as brown corundum, ceramic pills, resin particles) in the centrifugal force and the Under the action of friction, the surface of the 

    workpiece to produce high-frequency micro-impact and grinding; 

2. Polishing agent role: containing surfactants, corrosion inhibitors of the polishing solution, can remove the metal surface oxide film, lubricate the media and 

    accelerate the discharge of debris; 

3. Energy transfe：The vibration energy is uniformly transmitted to each workpiece, realizing “omni-directional dead-angle-free” machining, especially suitable

    for blind holes, grooves and other hidden areas.

Fourth, The core application of metal polishing 

Vibration polishing machine is widely used in industries that require high precision of metal surface: 

1. Hardware: deburring and mirror polishing of sanitary fittings (faucet, door handle), locks, jewelry fittings; 

2. Electronic communication: chamfering and precision polishing of cell phone frames (aluminum alloy/stainless steel), heatsinks, connector terminals; 

3. Automotive parts: de-oxidation and roughness optimization of engine valve plates, bearings, brake calipers; Aerospace: lightweight polishing of titanium 

   alloy structural parts, aviation bolts (avoiding stress concentration of traditional polishing). automotive components: engine valve plates, bearings, cages, brake

   calipers, oxidation removal and roughness optimization; 

4. Aerospace: titanium alloy structural components, lightweight polishing of aviation bolts (to avoid the stress concentration of traditional polishing).

Fifth, the analysis of the whole process of metal polishing (stainless steel parts as an example) 

1. Pre-treatment: workpiece and material preparation 

(1) workpiece requirements 

 ·To remove oil (cleaned with alcohol or degreasing agent), welding residues (grinding and smoothing); 

 ·Classification and screening: according to the size, material, polishing difficulty of the grouping (such as small-sized bolts and large-sized flanges are handled separately).

(2) Configuration of grinding materials

·Selection of abrasives 

 ·Rough grinding (deburring / rust removal): brown corundum abrasives (particle size 0.5-1mm, high hardness, suitable for stainless steel, cast iron); 

 ·Fine grinding (surface refinement): ceramic abrasives (particle size 0.2-0.5mm, rounded corners, to avoid scratches); 

 ·Mirror polishing: resin abrasives (elastic material, with the polishing paste to achieve the accuracy of Ra0.2μm below).

·Polishing solution ratio

 ·Water: polishing agent = 10:1 (adjusted according to the degree of oil contamination of the workpiece, the polishing solution containing anti-rust components 

  can prevent rust after processing).

2. Equipment commissioning and processing 

(1) Parameter setting: 

 ·Vibration frequency: 80-120Hz for rough grinding (high-energy impact), 50-80Hz for fine grinding (gentle grinding); 

 ·Processing time: 30-60 minutes for rough grinding, 20-40 minutes for fine grinding (adjusted according to the initial roughness of the workpiece);

 ·Load: not more than 70% of the volume of the grinding tank (to ensure that the media flow space).

(2) Operating steps: 

 ① Workpiece and abrasive, polishing solution poured into the grinding tank in proportion; 

 ② Start the equipment, observe whether the media movement is uniform (ideal state: spiral tumbling, no accumulation); 

 ③ Halfway through the machine can be stopped to check the effect of polishing, replenishment of polishing solution or replacement of abrasive (such as rough 

      grinding and then switch to fine grinding abrasive).

3. Post-processing: cleaning and quality inspection 

(1) Cleaning process: 

 ·Ultrasonic cleaning (to remove residual abrasives and polishing agents) → neutralization and antirust treatment (immersion 5% sodium nitrite solution, for steel parts) 

 → drying (hot air drying or centrifugal dewatering); 

(2) Quality Inspection: 

 ·Visual Inspection: no burrs, scratches, even surface color; 

 ·Instrumental inspection: roughness meter (Ra value up to standard), film thickness meter (suitable for inspection after plating polishing).

Sixth, metal polishing precautions 

1. equipment operation safety: 

 ·Wear protective gloves and goggles to avoid abrasive splash; 

 ·Regularly check the vibration motor screws tightness, to prevent abnormal vibration damage to the equipment.

2. Material matching principle: 

 ·Abrasive hardness needs to be higher than the workpiece material (such as aluminum parts to avoid the use of carbon steel abrasive, to prevent secondary scratches); 

 ·Polishing solution needs to be selected according to the characteristics of the metal (such as copper parts with ammonia polishing solution, stainless steel with weak acidic formula).

3. Optimization of process parameters: 

 ·Small pieces (<20mm) with high frequency and low amplitude, large pieces with low frequency and high amplitude; 

 ·First processing is recommended to do 5-10 pieces of small batch test, record the best parameters.

4. Maintenance: 

 ·Daily cleaning of residual debris in the grinding tank, weekly check the spring assembly elasticity (to avoid vibration attenuation); 

 ·Long term shutdown, empty the tank liquid and dry, to prevent abrasive caking and equipment corrosion.