Industry Knowledge

Question 1: Will the bearing steel rust?

Bearing steel, including stainless steel, is rusted. Although stainless steel is known as rust. In fact, there is no stainless steel in the world!

Question 2: Why did the bearing steel rust?

The so-called stainless steel, refers to the degree of corrosion resistance.

Corrosion rate < 0.01mm/y, considered as "complete corrosion resistance";

Corrosion rate < 0.1mm/y, it is considered "corrosion resistance";

If the corrosion rate is greater than 0.1mm/y, it is considered "corrosion resistant", that is, general steel.

In addition to a small part of bearing steel is stainless bearing steel, most of the bearing steel is ordinary corrosion resistant steel, so rust is not strange at all, very normal.

Question 3: Why do bearings rust?

Bearing rust is related to material and use environment. Bearing steel itself contains carbon components, which will react when encountering water vapor. Do not want to let the bearing rust to do a good job of rust prevention treatment, or choose non-steel bearings. Metal products, easy to rust after oxidation, stainless steel bearings are no exception.

There are many factors affecting its rust: such as the chemical composition and structure of the metal material itself; Surface finish (battery corrosion with poor oxygen concentration); The composition and pH value of the solution in contact with the metal surface; As well as its environment and many other factors, these are the direct factors of bearing rust. In addition, when we use bearings, do not touch items directly with your hands, because when sweat contacts with bearings, a layer of sweat film will be formed on the surface of bearings, sweat film will cause electrochemical effects on bearings, corrosion bearings. Therefore, we should use special gloves or finger sleeves and other special tools to take bearings, do not directly contact with hands.

Question 4: Will the steel bearing of GCr15 bearing rust in the outdoor environment?

Yes, and also like general steel will rust very badly, this steel contains too little Cr, bearing steel behind the value of Cr content, the unit is 1/1000, the Cr content of GCr15 is only about 1.5%, if the Cr content can be close to the boundary of 13%, the rust prevention effect is better. For example, Cr12 (containing Cr12% or so) class of steel is basically not much rust.

Question 5: Can bearing steel prevent rust?

Although the content of Cr in bearing steel is relatively high, it has certain anti-rust effect, but the content of Cr in steel is small, the content of Cr in GCr15 is only about 1.5%, at this time the Cr element is to improve the mechanical properties of steel, bearing steel Cr is to improve the hardenability is not used for anti-rust. As with metals in general, wet conditions can cause corrosion. Therefore, rust prevention measures of bearings and their parts are very necessary.

Question 6: How to prevent bearing rust?

1. Surface cleaning method: cleaning must be based on the nature of the surface of rust and the conditions at the time, select the appropriate method. Commonly used solvent cleaning method, chemical cleaning method and mechanical cleaning method. When the surface is dry and cleaned, it can be dried with filtered dry compressed air, or dried with a dryer of 120~170℃, or dried with clean gauze.

2. The method of coating anti-rust oil

(1) Soaking method: some small bearings are soaked in anti-rust grease and let the surface adhere to a layer of anti-rust grease. The thickness of the oil film can be achieved by controlling the temperature or viscosity of the antirust grease.

(2) brush coating method: for large bearings that are not suitable for soaking or spraying, it is necessary to pay attention not to produce accumulation when brushing, but also to prevent leakage coating.

(3) Spray method: some large bearings can not be oiled by soaking method. Generally, filtered compressed air at about 0.7Mpa pressure is used for spraying in clean air places. Spray method is suitable for solvent dilution type anticorrosive oil or thin layer anticorrosive oil, but must adopt perfect fire protection and labor protection measures.