The reformed process of needle roller bearing has proved that it can ensure product quality, shorten the process flow.

Generally, the process of drawn up of needle roller bearing is to punch and bend No. 08 or 10 steel sheet, conduct heat treatment, and then assemble the cage and needle roller The common disadvantage of this process is that the needle needs to be dropped after assembly, which affects the rotation In order to overcome this defect, our factory has carried out process reform.

During the trial production of 7942 / 15K needle roller bearing, KTH-930 protective coating supplied by the market was applied to the bending edge of the outer ring in the figure before the heat treatment of the outer ring. After carbonitriding, the working surface (cyaniding layer 0.14 ~ 0.16mm) contacted by the bearing outer ring and the needle roller not only met the metallographic and hardness requirements, but also avoided carbonitriding in the bending area, improved the toughness of the bending area, and made the bending process possible after the heat treatment, The needle roller in the bearing rotates flexibly without blocking.

Now the coating and heat treatment process are introduced as follows:

(1) Put KT-930 paint in a plastic container and stir it evenly with a wooden stick until it is paste.

(2) For degreasing of workpieces, boiling water containing 10 ~ 15% final sodium carbonate (Na₂CO₃) can be used until the oil is removed.

(3) Use a brush or fine brush to evenly apply the coating on the surface of the workpiece without atmosphere, and the coating thickness is about 0.6 ~ 0.8 mm.

(4) The heat treatment can only be carried out after the coating is naturally dried for 24 hours.

(5) The cyanidation process is carried out in the gas carburizing furnace. The workpiece is put into the carburizing furnace and heated to 750 ℃ for 46 ~ 60 minutes. After being taken out of the furnace, it is immediately cooled in oil, and then tempered at about 160 ℃ for 3 hours.

(6) Remove the oil and paint, boil in boiling water containing 10 ~ 15% sodium hydroxide until the oil and paint are removed, and then put into an anti-rust cylinder containing sodium nitrite 5 ~ 10%, calcium carbonate 0.5 ~ 1% solutions for anti-rust.

After the above process, install the needle roller and cage, and then bend the edge as shown in the figure.

After repeated tests, the reformed process has proved that it can overcome the above disadvantages, ensure product quality, shorten the process flow, and reduce from the past 15 processes to 10 processes.

1. Outer ring   2. Needle roller   3. Holder

More about ITS Needle Roller Bearing:

ITS needle roller bearing top quality brand has guaranteed production and highly active management.

A needle roller bearing is a special type of roller bearing which uses long, thin cylindrical rollers resembling needles. Ordinary roller bearings’ rollers are only slightly longer than their diameter, but needle bearings typically have rollers that are at least four times longer than their diameter. Like all bearings, they are used to reduce the friction of a rotating surface.

ITS needle roller bearings include HK Series bearing, BK Series bearing, HK...RS Series bearing, HK...2RS Series bearing, BK...RS Series bearing, K Series bearing, K...ZW Series bearing, NK Series bearing, NKS Series bearing, RNA49 Series bearing,

RNA69 Series bearing, NKI Series bearing, NKIS Series bearing, NA49 Series bearing,

NA69 Series bearing, NA48 Series bearing, RNA49...2RS Series bearing, and NA49...2RS Series bearing.