Solve the abnormal wear of the ball valves in the pulp transportation pipeline

The mining and beneficiation operations in regions such as Silesia in Poland focus on the efficient and reliable transportation of high solid content slurries. As a key control component in the pipeline system, the performance of ball valves directly affects the continuity of production and maintenance costs. However, the sharp mineral particles in the slurry, high flow rates, and potential corrosiveness have led to severe abnormal wear problems for traditional metal seat ball valves, manifested as increased internal leakage, increased opening and closing torque, and even rapid failure.

The wear of ball valves caused by the pulp conditions

The slurry is not a homogeneous fluid but a two-phase mixture of solid and liquid. The damage to the valves mainly results from two factors:

1. Abrasive wear
   • When hard particles such as quartz and metallic minerals pass through the valve under high pressure, they will exert microscopic cutting and scraping effects on the sealing surface (the ball and the valve seat). The PTFE soft sealing valve seat or the ordinary hardened metal surface will be rapidly scratched, damaging the sealing line and causing the seal to fail, resulting in internal leakage.
2. Erosion and Wear
   • At the points where the flow rate is reduced or changes direction, the high-speed particles continuously impact specific areas within the valve body cavity, which may lead to local material loss and thinning of the wall thickness. Eventually, this could result in a risk of shell leakage.

Core solution

The key to resolving abnormal wear lies in making the hardness of the flow-through components far greater than that of the abrasive particles.

1. Materials of flow through components: ranging from metals to high performance ceramics
   • Employing structural ceramic liners and ceramic spheres. For instance, manufacturing spheres, valve seats, and valve inner linings with pure alumina (Al2O3) or silicon carbide (SiC) with a purity of >99%. These ceramic materials have a Rockwell hardness (HRA) of up to 80-90, which is much higher than the hardness of most hard particles, thereby converting wear from "component wear" to "wear by the medium itself". This ensures that the geometric accuracy of the sealing pair is maintained over a long period of operation, fundamentally resolving the failure caused by wear.
2. Optimization of valve structure for pulp process conditions
   • Ensure that when the valve is opened, the flow channel is basically in line with the inner diameter of the pipeline, thereby reducing the risk of particle accumulation and jamming.
   • To overcome the possible accumulation of slurry on the valve ball surface, which may cause opening and closing resistance, an air actuator with sufficient torque and a safety factor (usually 1.5-2 times the calculated torque) should be configured. Additionally, it is necessary to ensure that its service life (such as 1,000,000 cycles) meets the requirements of the frequent switching process of the dust removal system.

For the Polish mining industry, adopting a wear-resistant ball valve solution with a core technology based on fully ceramic flow components, a structure optimized for the mineral slurry, and a matching heavy duty actuator, the enterprise can significantly extend the service life of key valves, reduce the overall cost of unplanned downtime and frequent valve replacements.