With the upgrading of domestic crushing equipment manufacturing technology, high manganese steel castings, as core crusher parts, are widely applied in wear-resistant components such as jaw plates and hammers. The production of these special cast steel components has distinctive process characteristics: it adopts a single-piece, small-batch production mode, primarily relying on manual sand casting technology. The quality control system involves multi-dimensional key factors.
1. Key Control Points in the Production Process Chain
● Structural Design and Process Adaptability
The geometric structure of crusher parts needs to balance wear resistance with the feasibility of the casting process, especially the transition areas of the wall thickness in high manganese steel castings, which must be optimized with rounded corners to avoid stress concentration. The casting process design should focus on the impact of the gating system on directional solidification, with process parameters optimized through numerical simulation technology.
● Melting and Alloying Control
The smelting of high manganese steel castings requires strict control of the carbon-manganese ratio (C/Mn ≈ 1/10), using an electric arc furnace plus refining furnace dual-process to ensure steel cleanliness (S, P ≤ 0.04%). Through argon stirring and vacuum degassing technology, the hydrogen and oxygen content is reduced to below 2 ppm, preventing porosity defects.
● Molding Sand System Management
A composite system of chromite sand and resin binders is used to ensure that the molding sand has a refractoriness of ≥1580°C, permeability >120, and wet compressive strength of 0.12-0.16 MPa. During molding, the compaction must be controlled within the 75-85 unit range to avoid sand expansion or insufficient permeability.
2. Process Quality Control Elements
● Precise Temperature Control
The pouring temperature is controlled at 1480 ± 20°C, with a stepwise pouring system to achieve sequential solidification. During heat treatment, furnace temperature uniformity (±15°C) must be ensured, and the austenitizing treatment temperature is strictly controlled in the 1050-1100°C range. The timeliness of water toughening treatment directly affects wear resistance.
● Environmental Parameter Monitoring
A constant temperature and humidity system is established in the casting workshop (temperature 25 ± 3°C, humidity 45 ± 5%), with dehumidification procedures applied during the rainy season. For high manganese steel castings, the box opening temperature should be controlled below 200°C to avoid cracks caused by residual stress.
3. Quality Defect Prevention Mechanism
● Establishing a Process Traceability System
From raw material entry to finished product shipment, a traceability system is implemented. 28 quality control points are set for key processes, increasing the defect detection rate to 99.6%.
● Failure Mode Analysis
For common wear failures in crusher parts, metallographic analysis is used to optimize the manganese-carbon ratio, ensuring that the initial hardness reaches above HB200. After work hardening, it can be increased to above HB500, significantly extending service life.
● Intelligent Transformation
3D printing technology for sand molds is introduced to solve the problem of forming complex structures. Machine learning algorithms are applied to optimize process parameters, improving the qualification rate of high manganese steel castings from 89% to 96.5%, with energy consumption per ton reduced by 18%.
The UT testing qualification rate for high manganese steel castings in Duma Mechanical Crusher Parts has increased to 98.2%, and the service life of the installed equipment has been extended by over 30%, providing reliable support for improving the quality and efficiency of the equipment manufacturing industry.
