Causes of Mechanical Seal Leakage of Polymerizer and Preventive Measures

Polymerizer is the main equipment for the preparation of polymer compounds, which requires high sealing. In the industrial field, people usually use non contacting mechanical seals, spring seals, gland packings, pump seals, elastomer bellow seals, etc., while polymerizer generally uses mechanical seal.

Leakage Point and Cause of Mechanical Seal

There are six leakage points in the polymerizer, namely, A: the seal between the dynamic and static rings (dynamic seal point), B: the seal between the dynamic ring and the shaft sleeve and the spring seat (dynamic seal point), C: the seal between the static ring and the gland (static seal point), D: the seal between the shaft sleeve and the shaft (static seal point), E: the seal between the spring seat and the shaft sleeve (static seal point), F: the seal between the sealing gland and the autoclave body (static seal point).

Seal leakage caused by seal ring failure: In the above six leakage cases, there are two dynamic seal points A and B. The leakage of A is mostly due to the wear of the end face of the friction pair, and the leakage of B is due to the frequent movement of the dynamic ring which causes the wear of the seal ring and thus the leakage. C, D, E and F are static seal points, and leakage is caused by seal ring failure.

Seal failure caused by the wear of dynamic and static rings: If the gas in the seal chamber is not discharged from the exhaust port regularly during the operation of the polymerizer, a small amount of gas entering the lubricating oil chamber from the relative movement of the lower friction pair will gradually accumulate in the lubricating oil chamber. When there is too much gas in the lubricating oil chamber, the lubricating oil level will be lower than that of the upper friction pair, so that the end face of the upper friction pair cannot be fully lubricated and worn.

How to Prevent Leakage of Mechanical Seal

Strengthen the pressure resistance and wear resistance of fluororubber seal ring. Although the fluororubber seal ring has high chemical stability, high temperature resistance and aging resistance, in order to better prevent the aging, cracking and swelling of the fluororubber seal ring from affecting the sealing effect, the manufacturer needs to improve the wear resistance and pressure resistance of the fluororubber seal ring and make better seal rings.

Prevent dry friction between dynamic and static rings. In order to ensure the long-term operation of the mechanical seal, it is necessary to check whether the internal isolation fluid of the mechanical seal is full, whether there is circulating cooling water in the cooling chamber of the mechanical seal, and whether each valve is in the correct state before the equipment is started. Regularly observe the liquid level indication of the booster tank to maintain the normal lubricating oil level. Keeping the cooling water unobstructed at all times can effectively control the vaporization of the liquid film and the overheating of the friction pair. Regularly exhausting the mechanical seal and refilling the lubricating oil can ensure the normal lubrication of the end face of the friction pair and guarantee the service life of the mechanical seal.