1. Keep the keyhole clean during normal use to prevent sand oil. Only when the key is not inserted into the lock cylinder, you can add carbon powder to the lock cylinder, or use a 2B pencil to draw some powder under the key and insert it. The lock cylinder is pulled repeatedly several times. This way, the lock cylinder is opened several times.
2. Never add cooking oil if the key is not inserted well, or if the key is not rotating well, the super B-class lock core, due to the high precision, the structure is complicated, the marble inside is several times more than the ordinary lock cylinder, after refueling It was good to open at the time. In a few days, because the dust is stuck, or the oil is dry, it is easy to cause the lock cylinder to be more difficult to open, so that repeatedly adding oil several times will cause the lock cylinder to be stuck or even scrapped.