Anti-corrosion Surface treatments
- General presentation of surface treatments on ball slides
- Standard treatments on CHAMBRELAN guideways
- Processing options according to materials or use
- Summary synoptic table
1 – General presentation of surface treatments on linear ball slides:
Anti-corrosion treatment highly contributes to the quality and service life of linear guides. Industrial applications where humidity, dust and corrosive agents may be present, create difficult conditions for the telescopic slides.
It is therefore important to choose the right surface treatment according to the end application in order to guarantee the reliability of the linear guidance systems.
All our surface treatments are selected to comply with environmental regulations: for example, the zinc plating used is in compliance with RoHS and REACH directives.
To guarantee the reliability and functionality of the steel telescopic slides, the elements are tested with “Salt Spray” (S.S.). Their resistance is expressed in hours before red rust on less than 5% of the surface. A standard defines the resistance and serves as a reference for comparative evaluation between different types of anti-corrosion treatments.
Samples of slides are therefore placed in a test chamber and sprayed throughout the test with a sodium chloride solution (5%) at PH 6.5 and a temperature of 35°C. An evaluation of the surface condition is carried out at regular intervals to measure the quality of the protection.
2 – Standard surface treatments on CHAMBRELAN guides
CHAMBRELAN telescopic slides, whether partial extension, full extension or super-extension, are used in a wide range of applications, such as access doors, pull-out drawers, gap fillers, etc. All standard CHAMBRELAN slides are supplied with an anti-corrosion treatment suitable for the majority of applications:
- The steel slides are protected by a white zinc coating. The process consists of an electrolytic treatment with passivation. It forms a protective layer on the entire surface of the part. With an average thickness of 10 microns, it resists salt spray for 400 hours.
- The aluminium slides are in colourless anodisation, which is given to resist to 250 hours before white rust.
- Stainless steel slides are pickled and passivated.
In some applications, the corrosion protection treatment requires special attention as the telescopic slides remain closed most of the time. Dirt and moisture are therefore trapped inside, making it difficult to evacuate them. Maintenance intervals, which can be long or even irregular, must also be taken into account. For this reason, we offer suitable surface treatments as an option:
- to increase corrosion resistance,
- for aesthetic reasons (black colour treatments),
- to increase the hardness of the profiles and thus resist vibrations or intense duty cycles by carbonitriding (addition of carbon on the surface) .
These different options can be combined with each other…
3 – Surface treatment options depending on the material used:
For steel guides we can offer:
- a black zinc plating with a S.S. resitance of 200 hours;
- a high corrosion resistance zinc plating with a finish that offers a 600-hour resistance to S.S.
- a nickel zinc plating with a resistance of 1000 hours S.S.
- In the particular case of vibrations or a high number of cycles, we can also treat our profiles with a carbo-nitriding process which increases the surface hardness up to 35 HRC, the standard steel profiles having a hardness of about 20 HRC.
With its oiled impregnation, it will resist between 150 and 250 h S.S.
This hardness treatment can be combined with an anti-corrosion treatment, such as zinc nickel to optimize its resistance.
For aluminium slides, the possible options are :
- A black anodic oxidation
- A hard anodic oxidation with a hardness of about 48 HRC
For stainless steel slides :
- For stainless steel, we can carry out an electrolytic polishing which improves the surface state and the aspect of the profiles.
The pro’s advice:
Combining an improved surface treatment with stainless steel ball bearings mounting offers an economical alternative to all-stainless steel slides with optimised corrosion resistance at a fraction of the price of an all-stainless steel slide.
Lubrication is also a key element for the life of the slides.
4 – To remember:
Simplified synoptic table of surface treatments according to the materials or use:
Stainless steel (304L or 316L)
|ZNJ : White Zinc
450 h S.S.
|OAI : Colourless Anodic Oxidation
250 h S.S.
|Scouring & passivation|
|ZNN : Black Zinc
250 h S.S.
|OAN : Black Anodic Oxidation||Electrolytic Polishing|
|ZNA : High strength zinc
600 h S.S.
|ZNK : Nickel Zinc
1000 h S.S.
|NIT : Carbo-Nitriding
hardness of 35 HRC
|OAD : Hard anodic oxidation
hardness of 48 HRC
For more information or technical advice, please contact us.