Which is a good surface treatment for customized Thermal oil heating roller from China manufacturer

Common treatment methods for roller surface of customized Thermal oil heating roller from China manufacturer include chromium plating, Teflon spraying and ceramic spraying. Some people often struggle, which is better?

It is necessary to start from the characteristics of these methods.

Among the three methods of customized Thermal oil heating roller from China manufacturer, chromium plating is the most commonly used. Chromium electroplating is divided into two categories: decorative chromium and hard chromium. The surface of the customized Thermal oil heating roller from China manufacturer is basically plated with hard chromium.

The thickness of chromium plating is mostly 0.1~0.2mm. Of course, it can be thicker or thinner, depending on the needs. If it is a customized Thermal oil heating roller from China manufacturer, it is generally recommended not to be too thick. The main reason is that the thermal expansion coefficient of chromium is relatively small, only half of that of steel. If it is too thick and heated quickly, it is easy to cause the surface cracking of the chromium layer. Therefore, the chromium layer thickness of most customized Thermal oil heating roller from China manufacturer is less than 0.012mm, and the chromium layer of high-temperature rollers is as low as 0.03~0.05mm. If it is an ordinary roller, there is no such requirement, and thickening the chromium layer is a common method to compensate for insufficient diameter.

The surface of the plated chromium layer does not look good and is very rough, which requires fine grinding. If you want to mirror, you should polish it. After polishing, the roughness of chromium layer can be very high, up to grade 14 (RA ＜ 0.0125mm). The service temperature of hard chromium is relatively high, and it can work stably at 500 ℃.

There are two types of Teflon Thermal oil heating roller from China manufacturer:

1) PTFE: usually green, some gray. PTFE is also known as the "king of plastics" and its chemical name is polytetrafluoroethylene. The spraying thickness is generally 0.03-0.04mm;

2) PFA: gray, the spraying thickness is generally 0.05-0.06mm, or thinner.

The surface roughness of Teflon Thermal oil heating roller from China manufacturer is not high, most of which are ra0.5~1.5. However, because of its own chemical properties, Teflon surface is usually used for occasions requiring anti sticking. Subject to the melting point of Teflon (usually 300~320 ℃), its service temperature is usually not higher than 260 ℃.

There are many kinds of heating rollers for industrial ceramic heat transfer oil, and the most common one is tungsten carbide (WC). Mirror surface (ra0.025~0.03) can be achieved. The coating thickness is generally ≥ 15 wires (0.15mm), and the maximum thickness can reach 30-40 wires (0.3-0.4mm). High hardness, up to hrc75~76. But the price is expensive. The price per unit area is about 10 times that of chrome plating or Teflon spraying.

There are two main thermal spraying methods for customized Thermal oil heating roller from China manufacturer ceramics: supersonic flame spraying and plasma spraying. Supersonic flame spraying conventional spraying material: wc-12%co; Wc-20co-7ni; Wc-10co-4cr; Cr3Cr2-20~25%NiCr； 316 stainless steel; Ni series superalloy, etc.

Customized Thermal oil heating roller from China manufacturer plasma spraying conventional spraying material: Al2O3; Al2o3-3%tio2; Al2o3-13tio2; Al2o3-40tio2; Co2O3; Zro2-8%y2o3; TiO2, etc. The surface roughness of sprayed ceramics is better than that of fluorone, but not as good as that of hard chromium. Taking WC as an example, the best roughness is only about Ra0.025.

In general, hard chromium plating Thermal oil heating roller from China manufacturer is the most common method with high cost performance; The main purpose of spraying Teflon is to prevent sticking; Sprayed ceramics have many functions, of which wear resistance is the most commonly used.

Which customized Thermal oil heating roller from China manufacturer is better should be selected according to the needs of its own process.