Mine rack quality appraisal

mine rack is based on the core principle of high load-bearing structure and dynamic stability synergy. By optimizing load distribution, anti-vibration performance and material strength, it achieves the synergy of equipment support stability, impact resistance and long-term service reliability. It is widely used in mining machinery installation, conveyor system support and heavy equipment fixation. In open-pit mines, it is used as a rigid base for crushers/screeners; in underground transportation, it meets the anti-vibration requirements of belt conveyor frames; in equipment maintenance areas, it ensures stable support for heavy lifting equipment. Compared with ordinary steel structures, mine frames have the characteristics of modular design, corrosion resistance and intelligent monitoring, and are the infrastructure for safe production in mines.

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

As the intensity of mining operations increases, related quality dispute cases have increased significantly. The judicial dispute focuses on:

1, performance index dispute: insufficient actual bearing capacity, resonance frequency exceeding the standard;

2, material defects: carbon equivalent of structural steel exceeds the standard, high-strength bolt torque attenuation;

3, process problems: welding seams are not fused, anchor bolt pre-tightening force deviation;

4, contract performance disputes: core configurations (such as anti-seismic dampers, intelligent monitoring modules) are not consistent with the technical agreement.

For litigation quality appraisal of mine racks, the following technical methods are mainly used:

1. Appearance inspection: Check whether there are cracks, deformations, rust and other defects on the surface of the rack to judge the appearance quality of the rack.

2. Dimensional measurement: Measure the actual size of the rack and compare it with the size required by the design to determine whether the rack meets the specifications.

3. Material testing: Extract rack samples for metallographic analysis and mechanical property testing to determine whether the rack materials meet the requirements.

4. Load test: Under design conditions, external loads are applied to the rack to evaluate its load-bearing capacity and stability.

The applicant, a mining company, signed a "Crusher Support Frame Purchase Contract" with a defendant, a manufacturer, agreeing on a maximum load capacity of 600t. The frame buckled and deformed locally during use. The manufacturer argued that it was caused by overloading and illegal operation.

identification analysis results:

The quality analysis expert group discussed and comprehensively analyzed the relevant information of the "mine rack", the contract technical agreement, the on-site investigation case materials and other data, and made the following quality analysis Opinion:

The yield strength of the main beam steel of the mine frame involved in the case is only 300MPa (agreement ≥355MPa), the weld unfusion rate is 12% (agreement ≤3%); the anchor bolt pretightening force deviation is ±20% (agreement ±10%), and the resonance frequency is only 5Hz (agreement ≥10Hz). The appraisal concluded that defects in materials and workmanship were the main causes of structural failure.

The mine rack quality appraisal report should include:

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

2, the rack model involved, design drawings, construction records;

3, testing methods and equipment list;

4, analysis of correlation between testing data and failure;