Extending the Life of Slick Lines: How Advanced Wear Technology Reduced Costs and Downtime in Mining

Introduction

A uranium mine was replacing its concrete slick line every 11 months at a direct cost of roughly $1.2 million each time. Today that same 530-meter line is engineered to last more than 20 years. This is how material science and application-specific testing turned a recurring failure into decades of expected service.

In mining operations, every hour of downtime comes at a cost. When critical infrastructure like slick lines wears out prematurely, operations face expensive replacements, production interruptions, and increased safety risks. Selecting the right wear-resistant materials can dramatically improve reliability while reducing long-term operating costs.

The Challenge: Severe Abrasion in Concrete Transport

A uranium mine was experiencing excessive wear on a newly installed concrete slick line. The 530-meter line transported concrete and shotcrete with solids concentrations of approximately 70–75%, creating an extremely abrasive operating environment. The casing was 9.625” and the initial throughput prior to failure was 50,000 cubic meters (1,765,733 cubic feet, 275 million pounds) and was composed of 46,000 cubic meters of concrete (1,6244,475 cubic feet) and 4,000 cubic meters of shot create ( 141,259 cubic feet) with an annual throughput of 65-95,000 cubic meters. The material was a gravity feed at 90 degrees.

Despite using hardened 15 mm casing, the pipeline consistently wore through before reaching one year of service. The failures were not random: wear concentrated. The wear of the existing line was not traceable because of the severe failure throughout the line, the estimate was the line failed at 9 months but the system was not pulled from service until 11 months.

Replacing the casing involved much more than simply swapping pipe sections. The process required:

• New casing and couplers
• Drill rig mobilization
• Drilling a new borehole
• Removing and rebuilding surface infrastructure
• Significant production downtime

The direct replacement cost alone was approximately $1.2 million CAD every 11 months, not including lost production.

Engineering the Right Solution

Rather than selecting a wear material based solely on hardness, extensive laboratory testing was performed to determine the most suitable overlay for the application.

Testing included:

• ASTM G65 abrasion testing 
• Reverse bend testing
• Charpy V-notch impact testing
• Through-hardness evaluation
• Photomicrograph analysis

These evaluations verified overlay performance, bonding quality, production consistency, and ensured the overlay would not negatively affect the casing’s structural properties.

Why Testing Matters

Industrial wear applications often involve multiple wear mechanisms occurring simultaneously. Abrasion, slurry erosion, impact, and material flow all influence component life.

ASTM G65 testing measures low-stress sliding abrasion resistance, making it an effective benchmark for comparing wear materials used in highly abrasive applications such as chutes, hoppers, truck boxes, and pipeline systems. Results are reported as volume or mass loss, lower loss means higher wear resistance, which lets very different alloys be ranked on a common, repeatable scale.

Additional slurry jet erosion testing simulated the high-velocity movement of abrasive material through pipelines, providing valuable insight into long-term field performance.

Selecting a High-Performance Overlay

Using the combined test data, Trimay selected an 8 mm spiral-applied Nano Borocarbide (TWP71) overlay on a standard L80 casing. The overlay is spiral applied, laid in a continuous helical weld bead along the pipe, which gives uniform, unbroken coverage across the full bore rather than discrete patches or seams that create weak points.

TWP71 is an iron-based submicron (near-nanoscale) borocarbide alloy that holds a maximum hardness of 68–71 HRc throughout the full depth of the overlay, not just at the surface. In a Slurry Jet Erosion testing, Trimay’s borocarbide overlays record mass Volume loss on the order of 2.02 substantially outperforming most Tungsten carbide and complex carbide alloys.