Does the humidity in the working environment affect the service life of bucket teeth?

Direct Impact: Humidity accelerates electrochemical corrosion of bucket teeth, damaging the metal structure.

Bucket teeth are often made of steel (such as mild steel, high-manganese steel, and alloy wear-resistant steel). In high-humidity environments, these metals form an electrochemical corrosion circuit with oxygen and moisture in the air. This can manifest as follows:

1. Mild Humidity (40%-60% relative humidity, such as on humid days)

Impact: A thin film of water will form on the tooth surface, but the corrosion rate is slow. In the short term (1-2 weeks), only minor rust will appear (mostly concentrated in the gaps between the tooth and the adapter, and on the exposed metal surface of the tooth tips due to wear).

Consequences: Rust will slightly damage the anti-rust coating (such as the factory paint or galvanizing) on ​​the tooth surface, but will not affect the internal metal structure. The impact on service life is minimal (possibly shortening the tooth life by 5%-10%).

2. Moderate humidity (relative humidity 60%-85%, such as outdoor operations during the rainy season or near rivers or lakes)

Impact: The water film thickness increases, and impurities in the air (such as dust and silt particles in the working environment) dissolve into the water film, forming a "more corrosive electrolyte solution" that corrodes 3-5 times faster than in mild humidity.

Consequences: Rust on the bucket tooth surface can expand from "points" to "flaky," even penetrating into tiny cracks in the tooth body (such as fatigue cracks caused during shoveling). Over long-term use (over one month), the effective wear layer of the bucket tooth can be gradually stripped away due to corrosion, leaving the once-hard tooth tips loose and brittle, making them more susceptible to chipping during subsequent shoveling.

3. Severe humidity (relative humidity > 85%), such as prolonged rain, wet underground mining operations, and offshore sea spray.

Impact: If the bucket tooth surface is constantly wet, or even in direct contact with standing water, corrosion can penetrate deep into the metal, causing deep rust (commonly known as rust-through). If the operating environment contains salt (such as salt spray from coastal operations), the combination of humidity and salt creates a highly corrosive combination, increasing the corrosion rate by 2-3 times.

Consequences:

Structural Damage: The connection between the bucket teeth and the adapter (such as the pin holes) can become "seized" due to rust, requiring subsequent tooth replacement, which may require violent disassembly and even damage the adapter.

Decreased Strength: Deep rust can cause a drop of more than 30% in the tensile strength and impact toughness of the bucket teeth. Alloy bucket teeth that were once able to withstand the impact of hard rock may break even when loading ordinary gravel.

Significantly Shortened Lifespan: In high humidity environments, the service life of bucket teeth may be 40%-60% shorter than in dry environments (e.g., a three-month lifespan in dry conditions may be only 1.5 months in high humidity).

Indirect Impact: Humidity Exacerbates Tooth Wear Through a Synergistic Effect

In addition to direct corrosion, humidity also combines with operating load and material properties to create a "1+1>2" wear effect:

1. Humidity + Abrasive Materials: Exacerbates "Corrosive Wear"

If the operating material is inherently abrasive (such as sand, gravel, or ore powder), high humidity can cause the material to adhere to the tooth surface.

On the one hand, the adhered wet material continuously rubs against the tooth, while the moisture in the material carries abrasive particles deep into the tooth wear surface, resulting in a dual wear effect of "abrasive + corrosive" (more than twice as fast as abrasive wear alone in dry conditions).

On the other hand, wet material clogs the tooth's "wear gap," preventing smooth material sliding during loading. This requires increased loading force, indirectly increasing the "impact load" on the tooth and further accelerating fatigue damage.

2. Humidity + Low Temperature: Induces Freeze-Thaw Corrosion (Extreme Scenario)

If high humidity is accompanied by low temperatures (such as temperatures below 0°C during winter in northern China), the water film on the bucket tooth surface will "freeze into ice":

When ice forms, its volume expands, stretching out tiny cracks on the tooth surface and causing them to widen.

After melting at elevated temperatures, water seeps back into the enlarged cracks. Repeated freeze-thaw cycles cause "honeycomb-like" holes to form inside the tooth, dramatically reducing its structural strength and ultimately causing it to "suddenly break" during loading (this type of damage is particularly common in mining operations during high humidity in northern winters).

The impact of humidity on bucket tooth life is essentially a combination of "corrosion" and "operational wear"—the higher the humidity, the faster the corrosion rate, the more pronounced the decline in the tooth's structural strength and wear resistance, and the more severely shortened its service life. Therefore, when operating in a humid environment (especially one with moderate or higher humidity, or a high-humidity environment containing salt), it is not enough to focus solely on the "wear resistance" of the bucket teeth. It is also necessary to prioritize "corrosion-resistant materials" and perform daily anti-rust maintenance to avoid "unnecessary wear" caused by humidity and reduce replacement frequency and costs.