1. Provisions on dimension datum
When the comparative measurement method is used to measure the dimensional tolerance of NSK Error Regulation imported bearings, the measuring blocks or standard parts are specified as the dimensional basis for comparative measurement.
The measuring blocks must comply with the provisions of the standard JB / t1078 measuring blocks, and the Error Regulation standard parts must comply with the provisions of the competent department of the manufacturer.
2. Provisions for measuring instruments
The instrument used in the Error Regulation measurement must be calibrated and have the accuracy and amplification ratio suitable for the measured NSK imported bearing.
For the measurement of the inner diameter or outer diameter of NSK Error Regulation imported bearing, it is stipulated in China that it is measured within the area with a large chamfer coordinate away from the south end of the ferrule,
while it is mostly stipulated in foreign countries that it is measured within the area with twice the chamfer Error Regulation coordinate away from the two ends of the ferrule.
4. Allowable measurement error
In principle, the measurement error can be less than 10% of the tolerance.
5. Probe radius and gauge pressure
In order to reduce the measurement error, we must strive to reduce the Error Regulation pressure measurement force of the measuring meter and increase the curvature radius of the probe within the possible range.
Therefore, it is necessary to Error Regulation continuously monitor the temperature of fag bearing, whether measuring the bearing itself or other important parts. If the operating conditions remain unchanged, any temperature change can indicate that a fault has occurred.
The regular measurement of fag bearing temperature can be aided by a thermometer, such as a digital Error Regulation thermometer, which can accurately measure the bearing temperature and display it in degrees Celsius or Fahrenheit.
Important fag bearing means that when it is damaged, it will cause equipment shutdown. Therefore, this kind of bearing should be equipped with temperature detector. Normally, FAG bearings will have a natural temperature rise after just lubrication or re lubrication and last for one to two days.
Generally, the bearing with operating temperature above 150 ° is called high temperature bearing. When the Error Regulation operating temperature of chromium bearing steel exceeds 150 °, its hardness will drop sharply and its size will be unstable, so that fag bearing can not work normally.
Therefore, for fag bearings operating at 150 ° to 350 ° operating temperature, if the ferrule and rolling element are still made of ordinary high carbon chromium bearing steel, special tempering treatment must be carried out for fag bearing parts, which shall generally be tempered at 50 ° higher than the operating temperature.
The bearing steel tempered according to the above requirements can be used normally at working temperature. However, due to the decrease of hardness after tempering, the service life of fag bearing is reduced.