Inner Ball

At Huazhe, we see the S620 as the "master key" for the replacement market. We designed it specifically for repairs. The mounting interface is universal. A mechanic can pick it up and put it in without struggling to make it fit. We visited many auto parts markets and repair shops across the country. We found that the biggest headache for mechanics is not the product quality itself. It is "I bought it but it doesn't fit" or "the angle is wrong when installed". The S620 was made to solve this exact problem.

We choose 40Cr alloy steel for this model and form it with die forging. This method gives us good material use and consistent quality between batches. For heat treatment, we use quenching and tempering for the whole part, plus high-frequency hardening just on the ball head. The tempering gives the rod good toughness and strength to absorb road shocks. The local hardening makes the ball surface hard, reaching HRC 58-62 for great wear resistance. The ball is precision cut and then polished until it is smooth. We control the surface roughness to Ra0.4 or less. This means a thin oil film forms on the ball when it moves, giving a smooth, oily feel instead of dry friction. Inside, we fill it with lithium grease, which works well in the wide temperature range found across most regions. The dust cover is made of NBR rubber. Together with the seal, it keeps mud, sand, and rain out completely.

We did a lab test, comparing the S620 with a well-known brand's similar product. We ran them on a wear tester for 72 hours straight. The change in the S620's ball joint clearance was 15% smaller than the competitor's. This means in real use, the S620 keeps its "tight" feeling longer, and the steering does not get loose. As one of Huazhe's most competitive lines, the S620 handles radial loads very well. It easily meets the steering needs of micro vans and trucks that carry goods every day. Its universal mount fits popular models like the Wuling Hongguang and Chang'an Star. With just one part in stock, you can cover a whole range of vehicles. We often say, "A good replacement part is one the repairman forgets about." The S620 is that product. Install it and forget it, because it will do its job quietly for a very long time.