The ball screw support seat is divided into a fixed end and a supporting end. The fixed end uses an angular contact ball bearing, while the supporting end uses a deep groove ball bearing. The ball screw and such a screw support seat are used together and the use effect is good. But some people don’t do this, and they confuse the real with the fake. Once they are discovered, the result is that they pick up sesame seeds and lose watermelons.
One day, our company sent a batch of screw fixing seats to customers. Because of the need to check some problems, the customer disassembled the screw fixing seats of two suppliers (here is a special statement that the screw fixing seat body, bearings and glands are integrated and professionally assembled, and cannot be disassembled).
As a result, it was discovered that the bearing used in the other screw fixing seat was not an angular contact ball bearing, but a deep groove ball bearing. Because of this, the customer returned all the fixing seats of the other supplier, withheld their payment and demanded a heavy compensation. This is a big loss! Later, the customer changed to use our screw fixing seat.
The ball screw support seat is a precision machine part, so why do some manufacturers risk using deep groove ball bearings at the fixed end of the screw support seat?
Because the price of high-precision angular contact ball bearings is several times or even dozens of times that of deep groove ball bearings, and the bearings are assembled inside and cannot be seen, some manufacturers are greedy for cheapness and sell fakes at risk.
What’s wrong with using deep groove ball bearings at the fixed end of the screw support seat?
The disadvantages are obvious. First, the life is shortened, because the ball screw will generate axial and radial forces on the fixed end during operation, and deep groove ball bearings can generally only withstand radial forces. In addition to radial forces, angular contact balls can also withstand certain axial forces. Therefore, the life of the fixed seat using deep groove ball bearings will be greatly affected;
Second, the operating noise becomes louder, because the steel balls in the angular contact ball bearings have a certain angle (such as 25°, 30°, etc.), which can automatically adjust the slight imbalance that occurs during the installation process. The other two paired angular contact ball bearings have zero clearance, while deep groove ball bearings do not have these characteristics at all. Therefore, the operating noise of the screw fixed seat using angular contact ball bearings is much smaller than that using deep groove ball bearings.
So how do you identify whether the fixed end of the screw support seat uses an angular contact ball bearing or a deep groove ball bearing?
There are two methods:
First, remove the oil seal at the fixed end, and you can see the number on the outer ring of the bearing. If it starts with “6”, it is a deep groove ball bearing, and if it starts with “7”, it is an angular contact ball bearing;
Second, press one of the bearings with your finger and turn the other bearing with your hand. If the bearing can rotate and there is a friction sound, it is a deep groove ball bearing, and if the bearing cannot rotate, it is an angular contact ball bearing.
