Precautions for Using Cemented Carbide Roller Rings

Cemented carbide roller rings are high-hardness, wear-resistant tool materials composed of tungsten carbide and binder metal. To fully utilize their advantages of high wear resistance, long service life, and efficiency in high-speed wire rod rolling, manufacturers must address the following precautions when purchasing and using cemented carbide roller rings:

1）Correct Selection of Cemented Carbide Grades for Each Finishing Rolling Mill

Before selecting the grade of cemented carbide roller rings for each mill stand, thoroughly understand the properties of each grade to ensure proper grade matching across all stands.

2）Installation of Cemented Carbide Roller Rings

The mounting and installation of cemented carbide roller rings must strictly adhere to the precision requirements of the design process. The fit between the roller ring, mill shaft, and tapered sleeve must be appropriate—neither too tight nor loose. If too loose, verify compliance with process specifications before installation. Clean the assembly surfaces of the roller rings, tapered sleeves, and shafts thoroughly. Never strike roller rings with hammers or hard objects during assembly.

3) Cooling During Rolling and Water Quality Requirements

During operation, roller rings are subjected to thermal corrosion, thermal fatigue, and thermal stress, which can easily lead to network-like thermal fatigue cracks. As these cracks propagate, severe cases may result in block-like spalling or even roller fragmentation. Cooling is critical to reducing the effects of thermal corrosion, thermal fatigue, and thermal stress on roller rings during rolling, preventing roller breakage, slowing crack propagation, and extending the service life of the grooves. Proper cooling is essential for maximizing the performance of cemented carbide roller rings. Key cooling specifications are as follows: cooling water temperature below 25°C, water pressure of 5–6 MPa, flow rate of 24–30 m³/h per stand. The water spray should be radial, angled at 15–30° relative to the roller ring’s rotation direction, with a jet width twice the groove width, and must be directed precisely into the groove. Avoid scattered or mist-like water spray.

Water quality requirements:

YGH series: Neutral or weakly alkaline water with pH ≥7.2

YGR series: Slightly acidic water with pH ≥7.2 or ≤7.2

Solid particle content: <15 mg/L

4) Determine Appropriate Rolling Volume

Micro-cracks in grooves are inevitable. When cracks reach a depth of 0.2–0.4 mm during rolling, immediately remove the roller for regrinding. Over-rolling accelerates crack propagation, increasing碎裂risk. Recommended rolling volumes:

Pre-finishing stands: ≥6000 tons

Finishing stands 1–2: ≥4000 tons

Finishing stands 3–4: ≥4000 tons

Finishing stands 5–6: ≥2500 tons

Finishing stands 7–8: ≥2500 tons

Finishing stands 9–10: ≥1500 tons

Sizing stands: ≥1200 tons

5) Groove Regrinding

Regrind grooves when micro-cracks extend to 0.2 mm depth. Ensure cracks are fully removed during regrinding; residual cracks will accelerate propagation in subsequent rolling, leading to碎裂. Recommended regrinding depths:

Finishing stands 9–10: 0.4–0.6 mm

Finishing stands 1–8: 0.7–1.2 mm

Pre-finishing stands: 1.2–2.0 mm