ARCOR® PC the smart choice for Hydraulic cylinder coating
Posted on Jul 31, 2024Hydraulic cylinders generate linear mechanical force using fluid from an external pump driven by a power unit. Converting mechanical energy into hydraulic energy, moving the liquid through a flow system for a variety of applications, such as pressing, pulling, pushing, or lifting. They are often used in places where heavy loads need to be moved, and can extend force from a few thousand pounds to thousands of tons.
There are two types of hydraulic cylinders: single-acting and double-acting. Single-acting cylinders use hydraulic power for one-directional force, usually extension, and rely on gravity or a spring for retraction. Double-acting cylinders can apply force in both directions.
You will find hydraulic cylinders in machinery and equipment across many different industries including construction, handling, agriculture & forestry, manufacturing, earth-moving & mining, & and beverage processing & packaging, deep sea, marine, metallurgy & power, robotics & production operation, waste management and transportation.
These applications often operate in corrosive environments, so a hard-wearing corrosion resistant coating is required. Traditionally hydraulic cylinders are coated with paint, powder coating and chrome plating. However, these are all barrier coatings and once damaged offer no protection. Rust will creep underneath these coatings causing the coating to blister and flake. Zinc plating is sometimes used to offer sacrificial corrosion protection on damaged areas; however, these are soft coatings and only effective on narrow areas of damage.
ARCOR® is a form of nitrocarburization, the treatment enriches the surface of ferrous materials with Nitrogen and a small amount of Carbon. The surface metallurgy and properties of ferrous materials are modified and yield several advantages.
Firstly, the formation of an intermetallic compound layer (iron nitride) which as very high hardness. Underneath this compound layer is a diffusion zone with hardness gradient which improves the fatigue and compressive strength of the part.
Secondly an oxidation step is performed to generate black oxide layer (Fe3O4).
Thirdly, an oiling step allows to impregnate the micro-porosities created on the top of the surface to.
These layers generated through ARCOR® process steps provide great performances regarding:
- Very high corrosion resistance, can exceed 400h in SST.
- Wear resistance, the different layers provides a sliding behavior diminishing scuffing.
- Shock resistance, thanks to deep hardness gradient enhancing mechanical properties.
- Friction behavior (sealing, stick-slip, friction coefficient), thanks to ceramic-like surface with impregnated porosities.
- No cracking and peeling, as the process is not coating but diffusion+conversion, the risk is greatly reduced.
Thus improving the operation of whole hydraulic cylinder and its durability.
A decorative black appearance can also be achieved by adding a polishing operation after the oxidation stage and then re-oxidizing. This commonly know as QPQ®(Quench Polish Quench) , which is a trademark belonging to the HEF Group and used by its propriety salt customers along with Tufftride®, Tenifer®, Melonite® & Nutride®. Arcor® PC is a fully optimized version of QPQ® only available through the TS global jobbing shop network. It creates an excellent surface to extend the lifetime of seals.
These benefits combined with the uncertainty surrounding the future use of chromium has seen an acceleration in the migration of customers moving to the ARCOR® PC process. Their feedback on the long-term performance of ARCOR® PC in operation is excellent.
Technique Surfaces UK (TSUK) located in Birmingham has the largest process tanks in the UK and is equipped with centerless grinding capabilities for pre & post operations. Please contact us if would like further information or need a quotation.
