Energy isolation considerations
When using double-valve isolation and empty-isolation method, try to ensure the sealing effect of the two shut-off valves, you can first use butter lubrication to meet the requirements, or use a substitute valve when possible.
If a leaking isolation valve cannot be repaired or replaced, and no alternative valve is available, the valve may be used for isolation when evaluated and approved by the production supervisor.
Single valve isolation
If a high risk condition is not involved, a shutoff valve can be locked and closed, or closed and hung, as a minimum for isolation during routine repairs.
Single valve isolation shall not be used in the following situations:
1. Serious leakage occurred when the valve was shut off
2. Pressure over 1480PSI or valve size over 6 inches
3. Caustic soda, acid or other toxic fluids exist in the process that seriously endanger the safety of personnel
Electrical power offsets are suitable for operation on circuits with rated voltages greater than 36 volts.
For electrical isolation, the operator's isolation lock shall be locked on the power switch of the device or on the appropriate circuit switch, or in both places. The isolation lock should be located as close as possible to the isolated device.
After the isolation, be sure to test the related electrical equipment before work (press the start button) to ensure the power isolation is correct.
If there are only a few isolation locations (usually circuit breakers or very few valves) it is recommended to hang the operating lock and the head of the person in charge of the work site directly on the isolation point instead of using the isolation lock box. At this point, the operator isolation card should be attached to the key and put into the operator's isolation key box.
Any work on a direct live line (400 volts or higher) requires two qualified persons to work together and apply for a work permit.
Mechanical energy isolation can be achieved by turning off or disconnecting.
If there is a spring, release the spring or use mechanical braking to release the spring energy.
When servicing a car, place the plug under the wheel to prevent movement.
Long-term energy isolation
Because the parts to reach the longer time or transformation and so on.
You can close the PTW at this point, but the energy isolation work sheet is kept in the "isolating in progress" folder, with an attachment to the PTW so you know the reason for the energy isolation in the future.