Well Integrity Technical Section

Ali Ahmed,

I had a similar situation 20 years ago when a perforating gun went off 'low order' and shot my tubing up while we were POOH with the guns.  We successfully repaired the well and returned it to production using less 'permanent' choices than you are planning here. Let's deal with the 2 issues in order of risk; tubing than annulus.

Tubing

The tubing problem is not uncommon with some sort of a restriction to wireline or coil.  Since you can still pump into the pay zone/perfs you have several options.  We chose to use cross link gel to seal off the perforations and isolate reservoir pressure, instead of resin or cement, because it was easy to remove from the tubing during either a workover or P&A.  We chose Temblok from Halliburton as it is easy to mix, comes in a variety of temperature ratings, and we had used it for other projects.  Other mud/fluid companies have similar crosslink products, not exclusive to Hall. The key is that this stuff is very easy to mix and pump and then after a few hours it cross-link gels and sets up into a gas impermeable plug. What is great about it from a workover stand point is that it is just a gel and can be easily washed out with a work string inside tubing or with wash pipe outside the tubing.  In our case we circulated through the perforations in the tubing and squeezed down  the tubing to create a several thousand foot gel plug that would prevent gas to surface.  Three (3) years later we finally got a jackup rig to do the workover and we had no gas problems during all that time. The workover went great, cut tubing above the plug, washed over the damaged guns, washed over remaining annulus plug and cut tubing above packer.  Checked for any more holes (none) and then washed out get with acid down to perfs, cleaned up perf damage, and put well back on production with a new tubing string ( I skipped a few workover steps here  :-) ). Tests for gel cross-link timing must be performed at well temperatures (hotter) or the crosslink will go off before expected. 

In your case, I would try something similar if you want to produce the well in the future.  Pump Crosslink pill down the tubing to seal off the pay zones and prevent pressure from the tubing and annulus. Your service company can advise but only a few hundred feet should be adequate.  Don't squeeze the Crosslink pill into the pay zone as it will go off and may not be removed if any depth of penetration. To avoid this you might pump an HEC hi vis pill in front of the Crosslink pill to seal off the perfs with a easy clean up pill.  After 24 hour curing time bleed off tubing and annulus pressures and check for leaks.  If no leaks set a plug in the hanger and make the tree safe.  If small leaks then, pull the 'NPC' and run a lock open sleeve across the SSSV.  This will allow you to run wireline and coil tubing in tubing. If additional annulus isolation is desired, punch some tubing holes and circulate around a second Crosslink pill. Now you are free to plan the workover or abandonment. The crosslink pill is easily washed away and can be dissolved with low concentrations  of HCL if required. So cut tubing, POOH and either workover the well or work your way down to a place to set abandonment plugs.  Let me know if you want more information.

Annulus

For the casing annulus injection I would be very careful in establishing injection rates before pumping any permanent sealing agent like gel or cement.  Typically these injection rates are measured in ounces/ minute down to ounces per hour. These rates are impossible to pump, in my experience, with gels or cement, as I cannot get the product to depth before they set and create a new 'trapped' annulus.  Sealing off the annulus with cement means the gauge pressures no longer reflect any pressures below your new 'plug'. This can be bad. 

From your description above, the issue appears to be a SCP of 600 psi, if I read that right.  You did not mention gas venting, but just pressure.  If the issues is just having a small fluid pressure build up, from a weak zone below the open shoe, then this is a very low risk of catastrophic failure and does not need a 'high risk' cement squeeze.  If I have that interpretation wrong please correct me.  I have worked with numerous Operators to risk assess these kinds of situations and develop monitoring plans to assess if conditions change, but otherwise avoid any more work to address.  In other words, a small water leak "blowing out" at 4 ounces per minute will take nearly 3 hours to fill a 5 gallon bucket.  This is a leak that can be easily mitigated. 

I hope this gave you a few alternative ideas to consider. Let me know if any question,

Ali Ahmed,

I had a similar situation 20 years ago when a perforating gun went off 'low order' and shot my tubing up while we were POOH with the guns.  We successfully repaired the well and returned it to production using less 'permanent' choices than you are planning here. Let's deal with the 2 issues in order of risk; tubing than annulus.

Tubing

The tubing problem is not uncommon with some sort of a restriction to wireline or coil.  Since you can still pump into the pay zone/perfs you have several options.  We chose to use cross link gel to seal off the perforations and isolate reservoir pressure, instead of resin or cement, because it was easy to remove from the tubing during either a workover or P&A.  We chose Temblok from Halliburton as it is easy to mix, comes in a variety of temperature ratings, and we had used it for other projects.  Other mud/fluid companies have similar crosslink products, not exclusive to Hall. The key is that this stuff is very easy to mix and pump and then after a few hours it cross-link gels and sets up into a gas impermeable plug. What is great about it from a workover stand point is that it is just a gel and can be easily washed out with a work string inside tubing or with wash pipe outside the tubing.  In our case we circulated through the perforations in the tubing and squeezed down  the tubing to create a several thousand foot gel plug that would prevent gas to surface.  Three (3) years later we finally got a jackup rig to do the workover and we had no gas problems during all that time. The workover went great, cut tubing above the plug, washed over the damaged guns, washed over remaining annulus plug and cut tubing above packer.  Checked for any more holes (none) and then washed out get with acid down to perfs, cleaned up perf damage, and put well back on production with a new tubing string ( I skipped a few workover steps here  :-) ). Tests for gel cross-link timing must be performed at well temperatures (hotter) or the crosslink will go off before expected. 

In your case, I would try something similar if you want to produce the well in the future.  Pump Crosslink pill down the tubing to seal off the pay zones and prevent pressure from the tubing and annulus. Your service company can advise but only a few hundred feet should be adequate.  Don't squeeze the Crosslink pill into the pay zone as it will go off and may not be removed if any depth of penetration. To avoid this you might pump an HEC hi vis pill in front of the Crosslink pill to seal off the perfs with a easy clean up pill.  After 24 hour curing time bleed off tubing and annulus pressures and check for leaks.  If no leaks set a plug in the hanger and make the tree safe.  If small leaks then, pull the 'NPC' and run a lock open sleeve across the SSSV.  This will allow you to run wireline and coil tubing in tubing. If additional annulus isolation is desired, punch some tubing holes and circulate around a second Crosslink pill. Now you are free to plan the workover or abandonment. The crosslink pill is easily washed away and can be dissolved with low concentrations  of HCL if required. So cut tubing, POOH and either workover the well or work your way down to a place to set abandonment plugs.  Let me know if you want more information.

Annulus

For the casing annulus injection I would be very careful in establishing injection rates before pumping any permanent sealing agent like gel or cement.  Typically these injection rates are measured in ounces/ minute down to ounces per hour. These rates are impossible to pump, in my experience, with gels or cement, as I cannot get the product to depth before they set and create a new 'trapped' annulus.  Sealing off the annulus with cement means the gauge pressures no longer reflect any pressures below your new 'plug'. This can be bad. 

From your description above, the issue appears to be a SCP of 600 psi, if I read that right.  You did not mention gas venting, but just pressure.  If the issues is just having a small fluid pressure build up, from a weak zone below the open shoe, then this is a very low risk of catastrophic failure and does not need a 'high risk' cement squeeze.  If I have that interpretation wrong please correct me.  I have worked with numerous Operators to risk assess these kinds of situations and develop monitoring plans to assess if conditions change, but otherwise avoid any more work to address.  In other words, a small water leak "blowing out" at 4 ounces per minute will take nearly 3 hours to fill a 5 gallon bucket.  This is a leak that can be easily mitigated. 

I hope this gave you a few alternative ideas to consider. Let me know if any question,

Ali Ahmed,

Your reply on SCP with a bleed of ~500ml and then a build-up back to the same pressure taking a 'week' is normal micro-annulus SCP response.   This is a leak that takes days to fill up a water bottle or a coke can. This gives a leak rate of 4 mls/hour for a 5 day buildup.  This is not a 'high risk' leak as it is not hydrocarbon and very, very  low rate. There is no risk of a jet fire and it just means that some low perm zone is able to flow up a micro-annulus to the surface.  

It will take a look at the original well construction records to determine which zones might be flowing and determine how the micro-annulus was created.  But this is a risk that can be monitored and bled off every week and monitored for a pressure change over time.

There is no way you can squeeze a leak that has a leak rate of 4 mls/hour with cement pumps or even conventional chemical pumps.  And blocking downhole, at some random place in casing annulus this leak can allow pressure to build up to some value that might not be understood but quite a bit higher than the current managed pressure.  Monitoring and Bleeding off is the much safer option, in my opinion.    

Ali Ahmed,

Your reply on SCP with a bleed of ~500ml and then a build-up back to the same pressure taking a 'week' is normal micro-annulus SCP response.   This is a leak that takes days to fill up a water bottle or a coke can. This gives a leak rate of 4 mls/hour for a 5 day buildup.  This is not a 'high risk' leak as it is not hydrocarbon and very, very  low rate. There is no risk of a jet fire and it just means that some low perm zone is able to flow up a micro-annulus to the surface.  

It will take a look at the original well construction records to determine which zones might be flowing and determine how the micro-annulus was created.  But this is a risk that can be monitored and bled off every week and monitored for a pressure change over time.

There is no way you can squeeze a leak that has a leak rate of 4 mls/hour with cement pumps or even conventional chemical pumps.  And blocking downhole, at some random place in casing annulus this leak can allow pressure to build up to some value that might not be understood but quite a bit higher than the current managed pressure.  Monitoring and Bleeding off is the much safer option, in my opinion.    

Ali Ahmed,

I had a similar situation 20 years ago when a perforating gun went off 'low order' and shot my tubing up while we were POOH with the guns.  We successfully repaired the well and returned it to production using less 'permanent' choices than you are planning here. Let's deal with the 2 issues in order of risk; tubing than annulus.

Tubing

The tubing problem is not uncommon with some sort of a restriction to wireline or coil.  Since you can still pump into the pay zone/perfs you have several options.  We chose to use cross link gel to seal off the perforations and isolate reservoir pressure, instead of resin or cement, because it was easy to remove from the tubing during either a workover or P&A.  We chose Temblok from Halliburton as it is easy to mix, comes in a variety of temperature ratings, and we had used it for other projects.  Other mud/fluid companies have similar crosslink products, not exclusive to Hall. The key is that this stuff is very easy to mix and pump and then after a few hours it cross-link gels and sets up into a gas impermeable plug. What is great about it from a workover stand point is that it is just a gel and can be easily washed out with a work string inside tubing or with wash pipe outside the tubing.  In our case we circulated through the perforations in the tubing and squeezed down  the tubing to create a several thousand foot gel plug that would prevent gas to surface.  Three (3) years later we finally got a jackup rig to do the workover and we had no gas problems during all that time. The workover went great, cut tubing above the plug, washed over the damaged guns, washed over remaining annulus plug and cut tubing above packer.  Checked for any more holes (none) and then washed out get with acid down to perfs, cleaned up perf damage, and put well back on production with a new tubing string ( I skipped a few workover steps here  :-) ). Tests for gel cross-link timing must be performed at well temperatures (hotter) or the crosslink will go off before expected. 

In your case, I would try something similar if you want to produce the well in the future.  Pump Crosslink pill down the tubing to seal off the pay zones and prevent pressure from the tubing and annulus. Your service company can advise but only a few hundred feet should be adequate.  Don't squeeze the Crosslink pill into the pay zone as it will go off and may not be removed if any depth of penetration. To avoid this you might pump an HEC hi vis pill in front of the Crosslink pill to seal off the perfs with a easy clean up pill.  After 24 hour curing time bleed off tubing and annulus pressures and check for leaks.  If no leaks set a plug in the hanger and make the tree safe.  If small leaks then, pull the 'NPC' and run a lock open sleeve across the SSSV.  This will allow you to run wireline and coil tubing in tubing. If additional annulus isolation is desired, punch some tubing holes and circulate around a second Crosslink pill. Now you are free to plan the workover or abandonment. The crosslink pill is easily washed away and can be dissolved with low concentrations  of HCL if required. So cut tubing, POOH and either workover the well or work your way down to a place to set abandonment plugs.  Let me know if you want more information.

Annulus

For the casing annulus injection I would be very careful in establishing injection rates before pumping any permanent sealing agent like gel or cement.  Typically these injection rates are measured in ounces/ minute down to ounces per hour. These rates are impossible to pump, in my experience, with gels or cement, as I cannot get the product to depth before they set and create a new 'trapped' annulus.  Sealing off the annulus with cement means the gauge pressures no longer reflect any pressures below your new 'plug'. This can be bad. 

From your description above, the issue appears to be a SCP of 600 psi, if I read that right.  You did not mention gas venting, but just pressure.  If the issues is just having a small fluid pressure build up, from a weak zone below the open shoe, then this is a very low risk of catastrophic failure and does not need a 'high risk' cement squeeze.  If I have that interpretation wrong please correct me.  I have worked with numerous Operators to risk assess these kinds of situations and develop monitoring plans to assess if conditions change, but otherwise avoid any more work to address.  In other words, a small water leak "blowing out" at 4 ounces per minute will take nearly 3 hours to fill a 5 gallon bucket.  This is a leak that can be easily mitigated. 

I hope this gave you a few alternative ideas to consider. Let me know if any question,

Ali Ahmed,

I am teaching in Kuwait this week so time zone closer to you than normal.

The microannulus has to be closed downhole by cement sqz perfs in the casing overlap or even section milling casing and setting a cement plug from casing to casing across the micro-annulus. I would consider each of those to have higher success rate than trying to sqz from surface.  It also allows you to monitor after the 'squeeze' to see if pressure builds up again. If it does repeat cement perf sqz and retest.   If you block the flow path to the valve you can't test if the leak is stopped downhole.  

Cement sqz has to be donw with a fine grained cement and very low sqz rates.  Use low fluid loss cement to prevent bridging across the perfs and allow injection behind pipe. 

Others might have some recommendations for squeezing a micro-annulus at surface casing.

Ali Ahmed,

Your reply on SCP with a bleed of ~500ml and then a build-up back to the same pressure taking a 'week' is normal micro-annulus SCP response.   This is a leak that takes days to fill up a water bottle or a coke can. This gives a leak rate of 4 mls/hour for a 5 day buildup.  This is not a 'high risk' leak as it is not hydrocarbon and very, very  low rate. There is no risk of a jet fire and it just means that some low perm zone is able to flow up a micro-annulus to the surface.  

It will take a look at the original well construction records to determine which zones might be flowing and determine how the micro-annulus was created.  But this is a risk that can be monitored and bled off every week and monitored for a pressure change over time.

There is no way you can squeeze a leak that has a leak rate of 4 mls/hour with cement pumps or even conventional chemical pumps.  And blocking downhole, at some random place in casing annulus this leak can allow pressure to build up to some value that might not be understood but quite a bit higher than the current managed pressure.  Monitoring and Bleeding off is the much safer option, in my opinion.    

Ali Ahmed,

I had a similar situation 20 years ago when a perforating gun went off 'low order' and shot my tubing up while we were POOH with the guns.  We successfully repaired the well and returned it to production using less 'permanent' choices than you are planning here. Let's deal with the 2 issues in order of risk; tubing than annulus.

Tubing

The tubing problem is not uncommon with some sort of a restriction to wireline or coil.  Since you can still pump into the pay zone/perfs you have several options.  We chose to use cross link gel to seal off the perforations and isolate reservoir pressure, instead of resin or cement, because it was easy to remove from the tubing during either a workover or P&A.  We chose Temblok from Halliburton as it is easy to mix, comes in a variety of temperature ratings, and we had used it for other projects.  Other mud/fluid companies have similar crosslink products, not exclusive to Hall. The key is that this stuff is very easy to mix and pump and then after a few hours it cross-link gels and sets up into a gas impermeable plug. What is great about it from a workover stand point is that it is just a gel and can be easily washed out with a work string inside tubing or with wash pipe outside the tubing.  In our case we circulated through the perforations in the tubing and squeezed down  the tubing to create a several thousand foot gel plug that would prevent gas to surface.  Three (3) years later we finally got a jackup rig to do the workover and we had no gas problems during all that time. The workover went great, cut tubing above the plug, washed over the damaged guns, washed over remaining annulus plug and cut tubing above packer.  Checked for any more holes (none) and then washed out get with acid down to perfs, cleaned up perf damage, and put well back on production with a new tubing string ( I skipped a few workover steps here  :-) ). Tests for gel cross-link timing must be performed at well temperatures (hotter) or the crosslink will go off before expected. 

In your case, I would try something similar if you want to produce the well in the future.  Pump Crosslink pill down the tubing to seal off the pay zones and prevent pressure from the tubing and annulus. Your service company can advise but only a few hundred feet should be adequate.  Don't squeeze the Crosslink pill into the pay zone as it will go off and may not be removed if any depth of penetration. To avoid this you might pump an HEC hi vis pill in front of the Crosslink pill to seal off the perfs with a easy clean up pill.  After 24 hour curing time bleed off tubing and annulus pressures and check for leaks.  If no leaks set a plug in the hanger and make the tree safe.  If small leaks then, pull the 'NPC' and run a lock open sleeve across the SSSV.  This will allow you to run wireline and coil tubing in tubing. If additional annulus isolation is desired, punch some tubing holes and circulate around a second Crosslink pill. Now you are free to plan the workover or abandonment. The crosslink pill is easily washed away and can be dissolved with low concentrations  of HCL if required. So cut tubing, POOH and either workover the well or work your way down to a place to set abandonment plugs.  Let me know if you want more information.

Annulus

For the casing annulus injection I would be very careful in establishing injection rates before pumping any permanent sealing agent like gel or cement.  Typically these injection rates are measured in ounces/ minute down to ounces per hour. These rates are impossible to pump, in my experience, with gels or cement, as I cannot get the product to depth before they set and create a new 'trapped' annulus.  Sealing off the annulus with cement means the gauge pressures no longer reflect any pressures below your new 'plug'. This can be bad. 

From your description above, the issue appears to be a SCP of 600 psi, if I read that right.  You did not mention gas venting, but just pressure.  If the issues is just having a small fluid pressure build up, from a weak zone below the open shoe, then this is a very low risk of catastrophic failure and does not need a 'high risk' cement squeeze.  If I have that interpretation wrong please correct me.  I have worked with numerous Operators to risk assess these kinds of situations and develop monitoring plans to assess if conditions change, but otherwise avoid any more work to address.  In other words, a small water leak "blowing out" at 4 ounces per minute will take nearly 3 hours to fill a 5 gallon bucket.  This is a leak that can be easily mitigated. 

I hope this gave you a few alternative ideas to consider. Let me know if any question,

Hello Ali,
It would be easier if you could provide some additional info. When dealing with degraded conditions fully understanding those and how you could / or not, break containment to start your operation...
Can you rig up on / operate your annulus valves? (break containment) Same question on your XT (kill wing or ideally top of XT)...
Barriers you could immediately install to facilitate repairs or install additional valves would typically be a VR-plug if your WH/TH is equipped with VR threads (hopefully yes). And a BPV in your Tubing Hanger. Let's start there...
Also, you mention your valves are passing... have you tried lubrication with specialty lubricants? JetLube or Clare (@Richard Grantham might be able to offer good advice) will typically have products which will be hard to pump, but could help regain a seal when you need it.

Rgds.

Hello Ali,

I suggest you post a few schematics here if you'd like support... wellbore and XT schematic would be a good start, and a well barrier envelope as you see it today... but otherwise fully agreed with comments above about lubricating and bleeding. If you only have a micro-annulus (slow P increase) you won't squeeze anything unless you punch holes before... a heavy brine might help you get this pbm sorted for now (see some annulus access capillaries like Expro's Octopoda for inspiration).

But again... if you'd like meaningful engagement from the community you need to help us help you, and this is with data. And it really needs to happen on this forum... otherwise (private) it's a bit more like free consulting ;)

Rgds.

Hi Alexis,

Not used it yet, just considered it a few times for SCP / Surface Casing Vent Flow... it does have merit although one has to be careful since in many cases remediating a charging annulus without addressing its source can make an issue even worse. I like the idea of controlling SCP using heavy brines (if you can) because they are not permanent / can be reversed. For more info on Octopoda you can get in touch with Lee Kazmierczak at Expro.

Rgds.

a bit confusing, but will offer a few more comments / opinions...

1. I've personally never seen cement of any kind cure a microannulus. especially from surface; resin may work, but is really just hiding the problem, or moving it further downhole (out of sight) and potentially causing more/different problems later.
2. the permanent solution is to first locate the source (of SCP), and shut off at that source.  Section milling can be effective but obviously at higher cost. So the "cost v severity" risk should be weighed.
3. As with normal cement, the fine-grind ('MicroMatrix' / HAL) cement has it's uses as well as limitations. eg, good for shutting off water through existing perf's, but never meant to be a permanent P&A solution. and limitations w/r to size of hole it can be pumped through.
4. seems to me there are two problems in this scenario; one is on the tubing side, other in the annulus side. without over-simplifying, the former appears to be manageable as a normal - but with some elevated risk - workover.  the latter can be dealt with - or not - once the producing zone has been sealed off, and production tubing has been removed.
5. don't do rigless; get a rig.  you'l be learning things long the way, so why limit yourself.