How the line spading controls can be put in place making sure that when unit is started back up with some spades still in place, there should not be any process or engineering concern?
Do not tell me that PSSR run should be the only one to assess this.
And if that is then should we be expecting participants in PSSR to closely perform engineering judgements as well? That too line by line?
Line spading controls
Re: Line spading controls
First of all, spaded lines during startup should be identified as part of permit system. If they are spaded, there must be an active permit. Or if spade has been put for a longer period of time and remaining system is charged up, there should have been an MOC in place support with some risk assessment supporting that line can be kept spaded with other associated system charged up.
But interestingly, spaded lines are normally picked up during PSSR only as most of the spading is done during shutdown opportunity.
But interestingly, spaded lines are normally picked up during PSSR only as most of the spading is done during shutdown opportunity.
Re: Line spading controls
Putting spades required a management of change process where you get your spade design approved through the committee.
Now this is when you are using spades while the system is down.
Once you are charging back up with some spades still in location, a risk review supported with change management process stands mandatory. Do not let that go unchecked as some of the times, we just blind one end of the line and take rest of the system in service. Yes, take the system in service after carefully looking into the spaded portion for any of the risk it might be carrying on the piping configuration of itself with the process system requirements.
Now this is when you are using spades while the system is down.
Once you are charging back up with some spades still in location, a risk review supported with change management process stands mandatory. Do not let that go unchecked as some of the times, we just blind one end of the line and take rest of the system in service. Yes, take the system in service after carefully looking into the spaded portion for any of the risk it might be carrying on the piping configuration of itself with the process system requirements.
Re: Line spading controls
Spade control should not depend on the PSSR team discovering, line by line, that a spade has been left in the wrong position. That is a weak control philosophy.
The better approach is to treat temporary spading/blinding as a controlled configuration of the process plant, with independent controls at several stages. PSSR then becomes a final verification, not the primary mechanism for discovering engineering incompatibilities.
The key principle is that every spade should have a defined purpose, location, status, owner, and required removal condition.
More importantly, the system should distinguish between:
Spades required for normal operation — intentionally left in place.
Spades installed for maintenance/isolation — must be removed before startup.
Spades whose continued presence is acceptable only under a defined operating condition — e.g., equipment out of service, alternate flow path available.
Spades that would create a process safety or equipment integrity problem if left installed.
The last category is where engineering judgement needs to be captured before startup, not improvised during PSSR.
The better approach is to treat temporary spading/blinding as a controlled configuration of the process plant, with independent controls at several stages. PSSR then becomes a final verification, not the primary mechanism for discovering engineering incompatibilities.
The key principle is that every spade should have a defined purpose, location, status, owner, and required removal condition.
More importantly, the system should distinguish between:
Spades required for normal operation — intentionally left in place.
Spades installed for maintenance/isolation — must be removed before startup.
Spades whose continued presence is acceptable only under a defined operating condition — e.g., equipment out of service, alternate flow path available.
Spades that would create a process safety or equipment integrity problem if left installed.
The last category is where engineering judgement needs to be captured before startup, not improvised during PSSR.
Re: Line spading controls
Once identified during the spading list review that there are some spades still in place, that should have triggered any system to take care of any risk of taking the system in operation.
That could have been an MOC process but practically this is not possible to assess the risk in detail during a PSSR or may be within PSSR, some member must have asked for change management to follow.
That could have been an MOC process but practically this is not possible to assess the risk in detail during a PSSR or may be within PSSR, some member must have asked for change management to follow.