Chrome plated bar is a well-known and very important material for many different industries, they are widely used to produce hydraulic cylinder and penumatic cylinders with honed cylinder tubing and some other accesorries. Besides this, chrome plated rods can be produced to Linear shafts for different machines. This product is made of steel round bars, but how is it manufactured in details? Here this article briefly introduces the manufacturing process of chrome plated bar.
Step 1. Purchase qualified raw material-Steel round bars
The raw material for chrome plated rods are steel round bars. Usually the chrome plated bar manufacturer will buy the steel round bars from the steel makers. In China, the most famous steel makers are Baosteel, Baotou Steel, Xinye Steel, Huai Steel, Shagang Steel and so on.
There are many different steel grades of the steel bars to make different chrome plated bars, including CK45 chrome plated bar, 1045 chrome plated bar, 4140 cromado bar, 42CrMo chrome plated bars,
After get the raw material, the factory need to inspect the raw material quality to make sure the raw material without any defects, which will lead the defects on the finished product.
Step 2. Get the steel bars / steel rods heat treated as per customers’ request.
Heat treatment is very important to chrome plated bar, with heat treatment, the mechanical properties will be greatly increased. There are two popular heat treatment process, one is Q&T (Quenching and tempering heat treatment), and the other is induction hardened heat treatment, chromed bar with this type of heat treatment is known as induction hardened chrome plated bar.
Step 3. Cutting the raw material round bar into lengths
If the required length for the chrome plated rods are with fixed length, the factory needs to calculate the length of the raw material and cut it to length and control the tolerance on length +/-2mm.
Step 4. Straightening the steel rods
Step 5. Peeling on the steel rods
To roughly remove the Scale and other Surface Defects by peeling.
Step 6. Straightenning
Step 7. Grinding the steel rods
Grinding the steel rods to the dimensions close to the finished dimensions.
Step 8. Straightening the ground steel rods.
Step 9. The second grinding process
Step 10. Polishing on outer diameter surface
Polish on the diameter of the steel rod to make the rod to the required dimensions and the the surface roughness of Ra 0.2μm to 0.4μm, to get the steel rods prepared for chrome plating.
Step 11. Chrome plating
Hard chrome plating the steel rods with a certain chrome plated thickness, such as min. 20 microns, 25 microns, … 50 microns. After chrome plating, the steel shafts now can be called hard chrome plated shaft.
Step 12. Final polishing
Here is the finishing polishing on the chrome plated outer diameter of the rods, to make the surface super smoothly, the roughness can be as good as Ra 0.2 microns (10RA).
Step 13. Final inspection
Do final inspection of the chrome plated rods, the inspection including dimension, straightness, surface roughness, hardness, chemical composition, and mechanical propterties.
Step 14. Packing the finished chrome plated shafts.
The finished qualified chrome plated shafts need to be well packed to prevent from any damages during moving and transportation. Usually the chrome plated rods /shafts are light oiled and packed with cardboard sleeves to protect the outer surface. After that, they will be put into wooden cases or packed in bundles for further transporation.
Here below is the manufacturing process flow chart of the chrome plated shafts.
