Thru-Tubing Casing Bridge Plug Running Procedures

This procedure is for a HIP™ Plug (an umbrella plug).

Thru-tubing plug-back operations can have a high success rate if the following principals are practiced.

• Read these recommended procedures prior to handling and running the plug.
  
• As a matter of field experience, dumping 20 feet (or more) of cement in 7 inch and larger casing has provided the highest plug-back success rates. Correspondingly, dumping fifteen feet (or more) of cement in 5-1/2 inch and smaller casing has provided the highest plug-back success rates. These cement plug lengths are recommended for all thru-tubing bridge plugs (regardless of the type or manufacturer).
  
• Although HIP™/WS models have provided many successful plugs without the use of supplemental bridging material, it is always advantageous to dump 1-2 Feet of additional bridging material atop the volume carried by the HIP™/WS. Supplemental bridging material is required when the well is deviated, there is cross flow, or open perforations in the wellbore.
  
• Keep the well static throughout the project until the plug is tested.
  
• Use HIP™ Mix to assure a high integrity cement slurry and plug.
  
• If the plug is to be run in a sour/corrosive environment, special preparations and/or a specially designed plug may be necessary. Contact HPI for more details.
  
• Prior to closing the vent valve, dump primary cement until it is within 12 inches to 18 inches from the vent ports.
  
• Wait a minimum of 18 hours after the last dump bailer run before closing the vent valve.
  
• Wait a minimum of 24 hours after the last dump bailer run before pressure testing the cement plug.
  

1.When you arrive on site, inspect the wellhead. If there is pressure at the surface, record the wellhead pressure. KEEP THIS PRESSURE STATIC UNTIL YOU HAVE COMPLETED THE PLUG BACK PROJECT. Pressure up the lubricator to wellhead pressure prior to opening the swab valve. Do this on every run.

2.CONTINUE TO MAINTAIN STATIC WELL CONDITIONS THROUGHOUT THE PROJECT. Make gauge run. Include thermometers to measure maximum temperature at plug depth. Identify and record fluid level. POOH.

CAUTION

HIP™ and HIP™ /WS are spring loaded in the setting sleeve. IF MISHANDLED, THE PLUG COULD PREMATURELY EJECT AND CAUSE SERIOUS INJURY. Never stand in front or behind the setting sleeve when loaded with a plug. ALWAYS HANDLE HIP™ AND HIP™ /WS WITH CAUTION.

3.Make up HIP™ with a CCL. One or two bow spring centralizers should be run immediately above the plug if the hole deviation is greater than 25o. For 7-5/8 inch and 9-5/8 inch HIP™, install at least 150 lbs. of weight bars above the HIP™ setting sleeve in the tool string.
NOTE: The HIP™ setting sleeve has a thick wall segment immediately below the threaded end. This segment is approximately 2-1/2 inches long. Whenever making up a tool string or placing the setting sleeve in a vise, pipe wrenches and vise faces should only clamp upon the thick wall segment. Do not clamp upon the thin wall tube below the thick wall segment.
The setting sleeve should be securely screwed onto the tool string so it will not back off while GIH or POOH. Pipe wrenches are generally used to secure the setting sleeve onto the tool string. Refer to Figure 1 for tool string make-up.

4.Run the HIP™ in the hole. Once you are at depth, carefully tie in with casing collars. Locate the HIP™ below the setting depth and slowly pull up to the desired setting depth. If the setting depth is not critical, it is recommended that the bottom set of slips be set 1 foot into a perforated interval or 1 foot below a casing coupling connection.
NOTE: The bottom end of the HIP™ ejects approximately 1 foot out the end of the setting sleeve when it is deployed. This must be added to the setting depth.
Deploy HIP™ at desired setting depth, wait 1 minute and pull off at 2,000 FPH for 50 feet. POOH. NOTE:If a HIP™ Plug is placed in the wellbore and not deployed for whatever reason, do not re-run this plug. Run a back-up plug and return the plug to HPI to be redressed.

5.Make up dump bailer to dump bridging material. Strap the entire CCL/bailer assembly to be certain that you can accurately locate the bottom of the bailer 2 feet above the vent valve. GIH with enough bridging material to fill 1-2 feet of casing volume. Locate the bailer 2 feet above the vent valve and dump. If the well deviation is greater than 60o, the bailer bottom should be located 2-3 feet above the packer when the bridging material is dumped. The bailer should them be stroked approximately 5 feet to encourage dumping of the shot. Stroke the bailer 3 to 5 times above the packer. POOH.

CAUTION:  RUNNING INTO THE PACKER MAY DAMAGE THE PLUG AND RESULT IN FAILURE. AVOID BAILER CONTACT WITH PACKER.

DEPTH CORRELATION IN DEVIATED WELLS

Since the bailer cannot be set down upon the packer, it is essential that the bailer depth correlation be determined while the tool is traveling downward and not while the bailer is pulled upward. This will allow accurate placement of the bailer bottom in deviated wells. The bailer bottom should be properly positioned while traveling downward and then the slack should be taken out of the line by picking up to the "tool pick-up weight". The cement or bridging material may then be dumped.

NOTE: Review the dimensional details of the plug and the casing. Be certain that the bailer can be placed in the annular gap between the plug and the ID of the casing. If it cannot, cement and bridging material should be dumped within 1-2 feet above the top of the plug.
Casing I.D. - 1.38")/2 > Bailer O.D.

6.Make up dump bailer to run HIP™ Mix cement. Strap the entire CCL/bailer assembly to be certain that you can accurately locate the bottom of the bailer 2 feet above the packer or 2 feet above the bridging material. Fill bailer with HIP™ Mix cement. GIH. Once the tool is within 20 feet of the vent valve, the rate of tool descent should be less than 1/2 foot per second (1,800 FPH). Carefully monitor line tension to assure the bailer does not set down upon the plug. Locate the bottom of the bailer 2 feet above the packer or 2 feet above the bridging material. Dump the slurry and wait 3 minutes. Do not shake a bailer with cement. POOH.

WELLBORE FLUIDS AND TRAVEL SPEEDS

The cement must be dumped in wellbore fluid, preferably a brine. The cement will not have adequate strength if dumped in dry gas, condensate, crude oil, or in wellbore fluid containing ligno-sulfanates. Once the first cement load has been dumped, you must not exceed the following travel speeds. This applies to GIH and POOH.
In 2-3/8 inches tbg maximum travel speed in liquid = 10,000 fph (166 fpm)
In 2-7/8 inches tbg maximum travel speed in liquid = 12,000 fph (200 fpm) In 3-1/2 inches tbg maximum travel speed in liquid = 18,000 fph (300 fpm) There is no limit to travel speed when the tool string is in gas. The maximum allowable travel speed only applies when the tool string is traveling in liquid and when the vent valve is open. Do not exceed the maximum allowable travel speed. Otherwise, you risk channelling and damaging the primary plug.

7.Repeat bailer runs until you have dumped enough HIP™ Mix to bring the top of cement to within 12 inches to 18 inches of the vent valve ports.

8.Wait at least 18 hours after your last dump bailer run before closing the vent valve. This will insure a properly cured and strong primary cement plug.

9.Make up an EL tool string having the following structure (from bottom to top):

• Lead impression block
• Bow spring centralizer
• Dump Bailer (if possible)
• Bow spring centralizer
• Remaining EL tool string

Or, make up a tool string having at least 150 pounds of weight bars, a lead impression block (with the largest possible diameter) on its bottom, and bow spring centralizers on top and bottom. GIH with tool string and set down on the top of the vent valve. Slack off at least 200 pounds to close the vent valve. You may jar down on the plug at 3,600-7200 FPH (1-2 FPS). Pick up and repeat two more times. POOH at safe and convenient travel speed. Inspect the lead impression block to confirm direct impact with the vent valve.

VENT VALVE CLOSURE

The force required to make an impression on the face of the LIB is greater than the force necessary to close the vent valve. Therefore, a ring type impression on the face of the LIB assures valve closure.

10.Make up dump bailer to run cement. GIH and dump cement to complete the plugging operations.

RECOMMENDED CEMENT PLUG LENGTH

The very best field performance has been experienced when 20 feet (or more) of cement is dumped in 7 inch, 7-5/8 inch and 9-5/8 inch casing and 15 feet (or more) of cement is dumped in 5-1/2 inch and smaller casing. Using this as a minimum benchmark, refer to plug length chart for cement length required for D P expected.

11.If the plug is to be pressure tested, wait at least 24 hours after the last bailer run before performing the pressure test.

FIGURE 1A - HIP™ /TOOL STRING MAKE-UP - EXPLOSIVE SETTING MECHANISM

1.Check make-up of all threaded connections prior to leaving shop.

2.Make a "Pig-Tail" (Item 3) and connect it to the "hot" pin (Item 2) at the bottom of the firing head. The "Pig-Tail" should be long enough (8"-12") to stretch through the HIP™ Double Box Window Sub (Item 4). Place insulation over the electrical connection, ensure it is fluid tight (i.e., electrical tape, boot, etc.). Secure with seizing with cord or clamp as appropriate.

3.Make up the EL Tool String (Item 1) to the HIP™ Double Box Window Sub. Stretch the "Pig-Tail" out the side window.

4.Insert a DuPont E-96 or E-141 squib into the open hole at the very top of the plug. Push the into the hole until it bottoms out. Secure the squib so that it will not come off the bottom of the hole.

5.Partially screw the HIP™ Setting Sleeve (Item 5) into the Double Box Window Sub. Pull the two leads of the squib so that they extend out of the side window. Securely make up all threaded connections in the tool string. Do not place a wrench on the body of the setting sleeve more than 2" below the threaded end.

6.Cut the two leads of the squib to length. Strip off the insulation to make the appropriate electrical connections.

7.Secure the ground lead from the squib to the ground screw in the Double Box Window Sub. Complete the "hot" "Pig-Tail" connection and secure the fluid tight boot over the connection. Push the wires into the window sub and insure that they cannot extend out of the window while RIH.

8.The plug is now ready to be RIH.

HPI, HIP & PSP are protected trademarks of High Pressure Integrity, Inc.