I. Purpose and Equipment Selection

1. Quality Control

   • Screening machines remove impurities and ensure particle uniformity. For example, stainless steel rotary drum sieves improve efficiency in soybean protein powder screening.

2. Equipment Selection Criteria

   • Material Properties: Vibrating screens are suitable for high-moisture materials, while electromagnetic-driven screens handle fine powders.
   • Precision: Multi-layer sieve configurations enhance grading accuracy, such as double-layer screens in fertilizer screening machines.

II. Operational Guidelines

1. Pre-operation Checks

   • Inspect sieve mesh integrity to prevent leakage (refer to linear screen maintenance standards).
   • Clean residual material to avoid cross-contamination.

2. Parameter Settings

   • Adjust amplitude and frequency based on material characteristics. High-amplitude screens improve efficiency for sticky materials.
   • Sieve aperture: Typically 2–2.2 times the target particle size (e.g., ≥200 mesh for fine particles).

3. Monitoring

   • Ensure uniform material distribution via horizontal rotation .
   • Troubleshoot reduced efficiency by checking mesh blockages or motor issues.

III. Common Issues and Maintenance

1. Fault Handling

   • Poor Screening: Clean or replace clogged/damaged mesh (e.g., fertilizer screen’s rotating disk design reduces leakage).
   • Abnormal Noise: Inspect bearings or loose fasteners (regular lubrication required).

2. Maintenance Cycles

   • Daily: Clean sieve surfaces and tighten bolts.
   • Periodic: Monthly mesh wear checks; annual replacement of wear parts (e.g., vibrating screen bearings last ~1,500 hours)[.

Doebritz China is a joint-venture of Doebritz German and some expert in China powder handling industry with rich experience. The mission of the company is to provide high cost-performance product to the market. At the moment, 4 major products are the key. Dosing valves from Doebritz German, FG sifters from British, tipping station and integrated tipping station, coating and mixing system.