1. Energy isolation method
1.1 Isolation of process flow, gas energy, hydraulic energy, thermal energy and mechanical energy
Precautions for blind plate isolation
A) Confirm that the diameter and thickness of the blind plate meet the requirements; B) Confirm that the equipment has been depressurized and emptied; C) Identify the products or materials that have been stored in the equipment or pipelines. If these substances are harmful, wear protective equipment; D) Reserve at least two opposite bolts when removing the flange bolts, then loosen the bolts but do not remove the nuts completely; E) The operator shall separate the flange from the side, and will not spray directly on people even if there is a sudden release of liquid and gas; F) New sealing gasket must be used when installing permanent blind plate to ensure energy isolation effect; G) The blind plate shall be installed on the flange nearest to the container or equipment.
Double truncation and discharge precautions
A) The sealing effect of the cut-off valve is good and should be locked; B) The automatic valve shall not be used as a cutoff valve. If the automatic valve is to be used as a cutoff valve, the valve must be closed first and then its automatic function shall be disabled; C) The size of the discharge valve shall meet the requirements of the maximum possible discharge flow that can pass through when closing the cutoff valve.
Separate precautions for single block valve
A) The sewage outlet of the upstream cut-off valve (if any) should always be opened during operation; B) Situations where a single cut-off valve is not allowed:
Pipeline and equipment pressure over 10MPa and valve size over 150mm.
There have been serious valve leaks.
The presence of acid, alkali or other toxic fluid that seriously endangers the safety of personnel.
1.2 Electrical isolation
When isolating electrical isolation, the lock used for isolation shall be locked on the power switch or appropriate circuit switch of the equipment, or locked in both places, and the position of the isolation lock shall be as close as possible to the isolated equipment;
Electrical isolation must be performed by a licensed electrician.
1.3 Selection of isolation method
According to the different effects of energy isolation, the blind plate isolation, double cutoff and discharge, and single cutoff valve isolation should be chosen as the priority in energy isolation scheme.
1.4 Lockout Tagout requirements
When implementing the above energy isolation methods, in order to prevent energy leakage due to misoperation, the way of locking must be adopted. If it is indeed impossible to lock, the warning board of "dangerous -- Do not operate" shall be hung on the equipment performing the energy isolation, and relevant personnel shall be informed.