Grain fan quality appraisal

grain fan is based on the core principle of synergy between aerodynamics and material transportation. By optimizing air volume adjustment accuracy, static pressure efficiency and energy consumption control, it achieves efficient transportation of grain particles, cleaning and impurity removal, and coordination of storage ventilation. It is widely used in grain warehouses, flour mills, feed processing, grain drying and other fields. In grain storage, it is used for uniform temperature and humidity ventilation of vertical silos; in the processing process, it meets the energy-saving needs of pneumatic transportation of materials; in the cleaning process, it ensures the efficient separation of light impurities. Compared with general-purpose fans, grain fans have the characteristics of strong dust-proof sealing, long wear-resistant life, and explosion-proof safety. They are the core equipment of grain storage, transportation and processing systems.

Zhongke Testing is a product quality appraisal service organization registered with the court. It can provide grain fan quality appraisal services. It has a professional appraisal team and advanced instruments and equipment to provide fair and accurate appraisal results for grain fan quality appraisal.

With the large-scale development of grain processing, related quality dispute cases have increased significantly. The judicial dispute focuses on:

1, performance index dispute: air volume is not up to standard, static pressure efficiency is insufficient;

2, material defects: impeller coating peeling, bearing seat casting porosity;

3, process problems: dynamic balance deviation, sealing structure leakage;

4, contract performance dispute: key configurations (such as explosion-proof motor models, frequency conversion control systems) are inconsistent with the technical agreement.

Grain fan litigation quality appraisal technical methods mainly include:

1. Appearance inspection: Check whether the model, specification, appearance, structure, etc. of the grain fan are consistent with the contract or standard requirements.

2. Performance testing: including testing of performance parameters such as air volume, wind pressure, head, etc. to verify whether the actual performance of the grain fan meets the design requirements.

3. Material testing: Conduct component analysis and strength testing on key materials of grain fans (such as impellers and casings) to verify whether the materials meet standard requirements.

4. Processing accuracy testing: Check the processing accuracy of the grain fan, such as the dynamic balance of the impeller, the sealing of the casing, etc., to evaluate the processing technology level of the equipment.

A grain depot of the applicant signed a "Centrifugal Grain Fan Procurement Contract" with an equipment manufacturer of the respondent, and it was agreed that the air volume should be ≥10000m³/h. After the operation was put into operation, uneven ventilation caused local mildew. The manufacturer argued that it was caused by the excessive resistance of the grain pile.

Identification analysis results:

The quality analysis expert group discussed and comprehensively analyzed the relevant information, contract technical agreements, on-site inspection case materials and other data of "Grain Fan", and made the following quality analysis opinions:

The actual air volume of the grain fan involved in the case was only 7800m³/h (agreement ≥10000m³/h), the impeller coating thickness was 0.8mm (agreement ≥1.2mm), and insufficient wear resistance caused blade wear to exceed 30%; the dynamic balance correction deviation caused a vibration value of 6.2mm/s (agreement ≤4.5mm/s).

The appraisal concluded that design and material defects were the main cause of insufficient performance.

Grain fan quality appraisal report should include:

1, purpose of appraisal (such as ventilation failure attribution, safety compliance verification) and reference standards;

2, involved equipment model, production batch, operation record;

3, testing method and equipment list (such as Wind tunnel test bench, vibration analyzer);

4, correlation analysis between test data and failure (such as the impact of insufficient air volume on ventilation uniformity);