Have you ever wondered why some gear systems fail even when they look perfectly fine from the outside? One hidden problem behind this damage is called micropitting. These tiny surface cracks may seem small at first, but they can slowly lead to serious gear and bearing damage if they are not controlled.
Today, gearboxes are used almost everywhere, including factories, cars, wind turbines, and high-speed trains. Modern gearboxes are becoming smaller and lighter, but at the same time, they are expected to handle more pressure and power. This extra stress increases the risk of micropitting and other wear problems. At Fubex Lubricants, we offer high-quality lubricants for all types of engines. Enjoy fast shipping, a price match guarantee, and no-questions-asked returns. Need help choosing the right oil? Call us at +971 50 544 9614 — our friendly team is ready to assist!
Awais I., Sales Director, says, “Understanding micropitting and how proper lubrication prevents it is not just about stopping tiny surface damage—it’s about protecting valuable equipment, avoiding unexpected failures, and ensuring smooth, reliable, and long-lasting industrial performance in every operation.”
In this article, we will explain what micropitting is, what causes it, how it affects gears and bearings, and how proper lubrication can help prevent costly equipment damage.
What is Micropitting?
Micropitting is a type of damage that happens on the surface of gear teeth. It can also appear in rolling element bearings. It creates very small cracks and tiny pits on the metal surface because of repeated pressure and friction during operation.
This problem can start within the first few hours of using the equipment. If it is not controlled, it may cause serious wear and even equipment failure. Many things can increase the chances of micropitting, but two major factors are rough gear surfaces and using the wrong lubricant.
Micropitting is not a new issue. As modern gearboxes started using case-hardened and carburized gears, the problem became more noticeable. Today’s gearboxes are designed to be smaller while still handling more power. Because of this, every part of the gearbox must perform better, including the gear lubricant.
What Problems Can Micropitting Cause?
Micropitting and pitting corrosion can cause serious damage to machines and equipment. This type of corrosion creates small holes or pits on the metal surface. Even though the metal loss may seem small, the damage can spread quickly in one area and weaken the equipment.
If the problem is not fixed early, it can cause leaks in pipes, tanks, and pressure vessels. This may lead to oil, gas, or other fluids dripping or escaping from the equipment. In small cases, the equipment may need to be shut down for repairs, which can waste time and money.
In severe cases, micropitting and pitting corrosion can damage the entire machine or system. It can also cause environmental pollution, expensive repairs, and dangerous accidents. In industries like petroleum, chemical plants, and nuclear power, pitting corrosion can create holes in pipe walls. This may result in large oil and gas leaks, fires, or explosions.
Pitting corrosion is responsible for around 20% to 25% of corrosion failures in the petroleum and chemical industries. Stainless steel is known for its strong resistance to corrosion because it forms a protective chromium oxide layer on the surface. However, pitting corrosion can still happen in some conditions.
For example, one factory built several stainless steel storage tanks using S30403 and S31603 stainless steel plates. After installation, the tanks were filled with firefighting water for testing. When the water was removed after three to four months, inspectors found severe pitting corrosion inside the tanks. Some tanks had more than 200 corrosion pits, and the deepest pits were nearly 5 mm deep, almost creating holes through the tank walls.
What is Micropitting in Gears?
Micropitting in gears is a type of small surface damage where tiny pits form on gear teeth over time. It happens when the metal surfaces keep rolling and sliding against each other under heavy pressure.
At first, these tiny pits are too small to see, but later they can look like dull or gray patches on the gear surface. This is often called “gray staining.” Micropitting usually happens when the oil film is too thin, the surface is rough, or the load and temperature are too high. Poor lubrication can make the problem worse.
If it is not controlled, micropitting can cause more wear, noise, vibration, lower machine efficiency, and even early gear failure.
How to Identify Micropitting Erosion?
Individual micropits are extremely small and cannot usually be seen with the naked eye. However, when many micropits appear together, they create dull or rough-looking areas on gear teeth. These areas may look less shiny than the rest of the surface.
To properly check for micropitting, the gear surface should be viewed under strong direct light from different angles. Bright lighting makes it easier to notice damaged spots. Normal fluorescent lighting may not clearly show micropitting damage.
How to Prevent Micropitting?
Micropitting can be reduced by using smoother gears and bearings, improving operating conditions, and choosing the right lubricant. One of the best and most practical solutions is selecting a high-quality lubricant designed to protect against micropitting.
The first step is choosing the correct lubricant viscosity grade. Simply using thicker oil is not always the best solution. Instead, it is better to use a lubricant with a high viscosity index and a low traction coefficient. A high viscosity index helps the lubricant maintain a strong oil film under different temperatures and operating conditions. A low traction coefficient helps reduce friction and surface fatigue.
Synthetic gear oils are often a good choice because they provide better protection against micropitting. In addition to viscosity, the additives inside the lubricant also play an important role. Some traditional EP additives may increase the risk of micropitting, while specially formulated lubricants can help lower this risk.
A good lubricant should not only reduce micropitting but also protect against wear, scuffing, rust, corrosion, foam, and water contamination. It should also work well with common seal materials used in gear systems.
Using the right lubricant, along with regular maintenance and inspections, can help extend equipment life, improve machine performance, and reduce costly downtime.
Bearing and Seal Failure
Seal failure is one of the most common causes of gear damage. When seals fail, dirt, water, and other contaminants can enter the system. This can damage the bearings and eventually lead to failure of the entire gear set.
Bearings can also rotate inside their housing and cause wear in the bore area. This may create misalignment, which can further damage gears and other machine parts. Bearings and seals are expensive components, so protecting them is very important.
Many of these problems happen when the lubricant becomes contaminated or loses its performance. Poor lubrication can increase friction, cause scuffing, and speed up wear on bearings and seals.
High-quality industrial gear oils are specially designed to help reduce these problems. These lubricants are tested under extreme operating conditions to make sure they can protect gears and bearings from wear, micropitting, and failure.
Industrial gear systems often work under very high temperatures. Because of this, gear oils must resist oxidation and stay stable during operation. Good lubricants should also separate water quickly to help reduce the risk of water contamination.
Choosing the right industrial gear oil and performing regular maintenance can help prevent small problems from turning into major equipment failures. This can improve machine performance, extend equipment life, and reduce costly downtime.
Final Takeaways
Micropitting may start as tiny surface damage, but if it is ignored, it can lead to serious gear and bearing problems over time. High friction, heavy loads, poor lubrication, and contamination can all increase the risk of micropitting in industrial equipment. That is why choosing the right lubricant is so important. A high-quality lubricant helps reduce friction, protect metal surfaces, control wear, and improve overall equipment performance.
Along with regular maintenance and inspections, proper lubrication can help extend machine life, reduce downtime, and keep industrial systems running smoothly and efficiently.
FAQs
Q1: What is micropitting?
Micropitting is a type of damage that creates tiny pits or cracks on bearings and gear surfaces because of high pressure and friction. It happens when the lubricant film is too thin to fully separate the metal surfaces.
Q2: How can you improve micropitting prevention?
You can help prevent micropitting by using the correct lubricant and making sure metal surfaces stay properly separated. Regular maintenance and reducing excess friction also improve equipment protection and performance.
Q3: What are three common mistakes when micropipetting?
Three common mistakes include not pressing the plunger fully, not releasing or dispensing liquid properly, and accidentally drawing air bubbles into the tip. These errors can cause the measured volume to be lower than needed and affect accuracy.
Editor-at-Large
A passionate writer in the lubricant industry, Awais Iqbal has been covering oils, greases, and industrial fluids since the start of his career. At 25, he’s already written for blogs, catalogs, and brand guides across the UAE. Awais’s insights help companies connect with their audience, and his clear, helpful writing style is trusted by brands in the region.