Let’s discuss what requirements there are for the intermittent operation of the catalytic slide valve
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Let’s discuss what requirements there are for the jog operation of the control room valves in each of our catalytic units Could an accident occur if the jog operation in the control room is not performed as required?
This post was last edited by aqshhsq on 2012-10-21 at 19:59. The operation of the spare accumulator for the catalytic converter slide valve is also known as jog operation. When a fault occurs in the main oil supply system, such as an interruption in the power supply to the oil pump motor or a malfunction in components like the hydraulic pump, and a low system pressure alarm is triggered, operation can be carried out using the backup accumulator. Therefore, there are two operating conditions: 1. The system pressure is low and an alarm is triggered ； 2. The manual directional control valve is in the “automatic” position (not in the “locked” position). Operation steps: In the DCS, bring up the control points related to jog operation. On the control point screen, change the status from “OFF” to “ON”, and then perform the jog operation by adjusting the OP value of the original control system. If the operation is not carried out as required or if the conditions are not met, jog operation will not be achieved. Since the electromagnetic directional control valve, which is used to implement the manual operation function, is in a de-energized state under normal conditions, its contacts close and it becomes energized when the system pressure is low and an alarm is triggered. When the manual directional control valve is in the “automatic” position, the pressurized oil from the backup accumulator can flow back into the system (under normal conditions, the backup accumulator allows oil to flow in only in one direction). The solenoid-controlled valve then regulates the opening and closing of the spool; the pressurized oil from one backup accumulator can be used to operate the spool over its full stroke.
First, get in touch with the control room to obtain permission for jog operation, then turn the knob on the local actuator to the jog position to carry out the jog operation; after that, turn the knob back to its normal position and contact the control room to have the permission revoked, so as to prevent anyone on site from performing accidental operations