How to maintain insulation joints?
Insulation joint is used to break the current flow of an underground pipeline that is equipped with cathodic protection.If the performance of the insulation joint is abnormal and you don’t know, there will be serious consequences.Regularly maintain insulation joints performance,it’s very import.(How to judge the performance of insulated joints?)
Common maintenance methods are as follows:
1.Check the ground potential of the pipe on both sides of the insulation joint regularly. If there is any difference from the original record,you should identify its performance. If there is leakage, you should take corresponding measures in time
2.Can judge the insulation performance of the insulating joint through measuring the potential on both sides of the insulating joint.
The potential of the non cathodic protection side is much more positive than that of the protection side. The potential difference is generally between 200 and 500 mV. If the potential difference is less than 100 mV, other measures should be taken to determine whether the connector is short circuited. The left side of the insulating joint is to block the current path so that it is limited in the pipe section.
3.The insulation joint shall be tested to ensure that it has good insulation performance.Remove the zinc grounding battery when testing.After the insulation joint is buried, the resistance of the insulation joint cannot be measured directly. At this time, the measured resistance value mainly depends on the length of the pipeline on both sides of the insulation joint, the status of the anti-corrosion coating and the soil resistivity.The insulation resistance of the insulated joint can be measured with the soil resistivity meter, and the resistance value measured after the joint is buried shall be greater than 0.01 ohm.
Once the insulation joint leaks,it can’t be repaired. It needs to be replaced to ensure the normal operation of the cathodic protection system. If the leakage is caused by stress deformation, repair welding can be used to eliminate it quickly.As a professional supplier,Hebei Haihao Group offer product and advisory services.