Jet Research Center Drill Collar Severing Tool (DCST)

Transcription

1 Jet Research Center Drill Collar Severing Tool (DCST) Field Loading Procedures WARNING Refer to and apply the procedures listed in the Recommended Practices for Oilfield Explosives Safety; API Recommended Practice 67 (RP67) before assembling or using this product. Explosives are by nature destructive. If mishandled or misused, the outcome may be immediate and disastrous, and may result in serious injury or death. Do not attempt to use this product unless you have received training in the handling and use of oilfield explosive products. The following Field Loading Procedures must be explicitly followed without attempts to shortcut, alter, switch or otherwise deviate in any way, or use alternate parts from those intended to be supplied by Jet Research Center for such field assembly. Use Utmost Care! JRC warrants only title to the equipment, products, materials, and supplies and that the same are free from defects in workmanship and materials. THERE ARE NO WARRANTIES, EXPRESS OR IMPLIED, OF MERCHANTABILITY, FITNESS OR OTHERWISE WHICH EXTEND BEYOND THOSE STATED IN THE IMMEDIATELY PRECEDING SENTENCE. JRC s liability and Customer s exclusive remedy in any cause of action (whether in contract, tort, breach of warranty or otherwise) arising out of the sale or use of any products, supplies or materials is expressly limited to the replacement of such products, supplies or materials on their return to JRC or, at JRC s option, to the allowance to be Customer of credit for the cost of such items. In no event shall JRC be liable for special, incidental, indirect, punitive, or consequential damages. Page 1 of 20

2 This Field Loading Procedure should be followed in conjunction with the assembly and application of the following listed Jet Research Center, Drill Collar Severing Tools: 1-3/8 in OD (35.1 mm) HMX 1-3/8 in OD (35.1 mm) HNS 1-3/4 in OD (44.5 mm) HMX 1-3/4 in OD (44.5 mm) HNS 2 in OD (50.8 mm) HMX 2 in OD (50.8 mm) HNS 2-5/8 in OD (66.5 mm) HMX 2-5/8 in OD (66.5 mm) HNS 2-1/8in OD (54mm) High Pressure HMX 2-1/8in OD (54mm) High Pressure HNS Page 2 of 20

3 Table of Contents Section 1 General Safety Precautions... 4 Section 2 Description and Specifications... 5 Section 3 Best Practices 6 Section 4 Assembly of the Drill Collar Severing Tool 9 Section 5 Arming and Deployment Procedures with Electric Detonators Section 6 Disarming and Disassembly Procedures with Electric Detonators Section 7 Parts List and Assembly Diagrams List of Tables Table 1 Drill Collar Severing Tools... 6 Table 2 Required Assembly Tools List... 9 Table 2b Required Hardware and Explosive Material List 10 Table 3 Required Parts List Table 4 Drill Collar Severing Tools Parts List List of Figures Figure 1 Example of failed cut attempt above drill collar connection 7 Figure 2 Example of subsequent successful cut attempt directly across drill collar connection 8 Figure 3 DCST Assembly Drawing (DWG D ) 21 Figure 4 2-1/8 HP DCST Assembly Drawing (DWG D ) 22 Page 3 of 20

4 1. General Safety Precautions Do not attempt to use this product unless you have received training in the handling and use of oilfield explosive products. Refer to and apply the procedures listed in the Recommended Practices for Oilfield Explosives Safety; API Recommended Practice 67 (RP67) before assembling or using this product. Failure to follow the assembly instructions can result in extensive bodily injury and death. Do not throw, slide, or roughly handle boxes of explosives. The assembly and arming of the cutters should only take place at the job site where they are to be used and immediately prior to running the cutter into the pipe. If there is any delay the device should be disarmed and safely stored. Load only in designated areas. Floors are to be covered with rubber mats. No open flames, welding, or sparking devices are to be used in the loading area while handling explosives. No smoking in the loading area while handling explosives. No RF-transmitting devices such as cellular telephones, two-way pagers, or hand held radios are to be in the loading area. Never strike, drop, force, heat, grind, drill, or hammer on any explosive item or explosive assembly. Use only the tools designed to be used with or for explosive loading. Do not attempt to alter or modify any part of the assembly. Use only manufacturer approved parts. Use only the proper razor blades and cutting blocks to cut detonating cord. Never use side cutters, pocketknives, scissors, or a cap-crimpier to cut detonating cord. Aluminum covered detonating cord is cut using a small pipe cutter. Always use approved methods and carriers for the transportation of explosives to the job site. Do not handle explosives when electric storms (thunder and/or lightening) are in the immediate area. Do not handle explosives in a sandstorm or similar situation that can result in the build-up of static electric charges. Page 4 of 20

5 2. Description and Specifications Jet Research Center s (JRC) Drill Collar Severing Tools (DCST) are designed to sever drill pipe, heavyweight drill pipe, and drill collars quickly and effectively. If pipe, collars, or bits become stuck, it is recommended that the Severing Tool is shot above the stuck point so that the free pipe can be recovered. These tools are also useful when restrictions preclude the use of conventional drill pipe and casing cutters. Select the largest O.D. severing tool that will pass through the minimum restriction in the drilling assembly. It is best to have the appropriate size tool available in the event the restriction changes during the pipe recovery operation. The JRC DCST uses a unique dual end firing system, which simultaneously initiates both ends of an explosive column. The detonation wave fronts collide at a centrally located cartridge that shapes the high energy into effective severing action. The Severing Tool incorporates safe arming procedures, utilizing detonator assemblies and safety assembly equipment. An o-ring secures the detonator ground wire into a groove on the mandrel, ensuring the detonator is properly grounded. A shunt plug maintains the system electrically shorted during assembly as the detonator shunt wire is removed. A protective holder encompasses the detonator, shielding the Explosive Supervisor, while the electrical connection is made to the CCL. The DCST uses Resistorized detonators, minimizing the chance of an accidental firing. The DCST can also be initiated using a Top Fire RED detonator, providing additional safety enhancements when compared to conventional Resistorized detonators. These tools can perform in hostile environments. In standard tools, the explosives allow the tool to function properly at temperatures up to 400 F (204 C) for one hour and at pressure ratings up to 15,000 PSI (103 MPa). High Pressure (HP) accessories can be used to achieve a pressure rating of up to 20,000 PSI (138 MPa). The DCST tool with HNS explosive is rated for 460 F and one hour. In cooler temperatures HMX has better performance values than HNS. The 2-1/8in High Pressure DCST can function at a pressure rating of up to 26,000 PSI (179 MPa). JRC s severing tool utilizes a shock absorbing extension mandrel that minimizes damage to uphole tools. The unique shock grooves dissipate the detonation shock waves transmitted up the tool. JRC recommends using centralizer tools to obtain maximum performance of the DCST. These tools connect back to the wireline through widely available firing heads. Avoid shooting a severing tool in or near the same place as a previous severance attempt, as this may reduce the optimum function characteristics for severing the target. Six (6) feet is a recommended minimum distance. Page 5 of 20

6 Description Loaded Tool Explosive Weight Will Sever Up To: Temperature Rating Pressure Rating Standard Tool With HP Acessories 1 3/8" OD X 36.5" - HMX 589.2g 3 1/2" Drill Collar 400F 15,000psi 20,000psi 1 3/4" OD X 36.5" - HMX 993.5g 6 1/2" Drill Collar 400F 15,000psi 20,000psi 2" OD X 36.5" - HMX g 8" Drill Collar 400F 15,000psi 20,000psi 2 5/8" OD X 36.5" - HMX 2355g 11" Drill Collar 400F 15,000psi 20,000psi 2 1/8"OD HP X 36.5" - HMX g 8" Drill Collar 400F 26000psi 1 3/8" OD X 36.5" - HNS 589.2g 3 1/2" Drill Collar 460F 15,000psi 20,000psi 1 3/4" OD X 36.5" - HNS 993.5g 6 1/2" Drill Collar 460F 15,000psi 20,000psi 2" OD X 36.5" - HNS g 8" Drill Collar 460F 15,000psi 20,000psi 2 5/8" OD X 36.5" - HNS 2355g 11" Drill Collar 460F 15,000psi 20,000psi 2 1/8" OD HP X 36.5" - HNS g 8" Drill Collar 460F 26000psi Table 1: Drill Collar Severing Tools 3. Best Practices In general it is advised to run the largest size of severing tool that can pass through the wellbore restrictions when shooting in open hole. In the case of severing tool operations, the main objective is to shoot the pipe in open hole to free the pipe. Since the DCST is typically the cutter of last resort for recovery operations, a successful cut is more important than if the recovered pipe is flared, split or otherwise damaged. For maximum efficiency, the best option when the DCST is used for drill collars is to shoot the connection (shooting the box side of the connection is ideal but generally difficult to be too precise with the positioning). If the DCST is used to cut drill pipe, the cut can be made at either the connection or in the tubular section of the joint. Drill pipe has a thinner wall in the tube and the cut may be more effective. Care should be taken when positioning the DCST for the shot. Depending on conditions, cable creep (relaxation) can move the DCST off depth from the intended shot depth and result in a failed attempt. The DCST differs from a jet cutter. A Jet Cutter produces a jet which radiates in a plane to achieve a cut. The DCST shock wave is generated by an explosive collision resulting in a spherical wave radiating from the center of the device. See the photos below for examples of a DCST fired directly above a drill collar connection, which failed, and a subsequent cut directly below the first attempt but in the connection which was successful. Page 6 of 20

7 For maximum effectiveness, a Free Point Log should always be run prior to any cutter so the cut is made at the proper depth. The tool will not free the string if initiated below or at the stuck section of pipe. If possible, tension should be applied to the drill string prior to tool initiation in order to increase the likelihood of severance. The amount of over pull to be applied above string weight at the desired cut depth should be determined by the drilling representative and not exceed safe working limits of the pipe. Figure 1: Example of failed cut attempt above drill collar connection Page 7 of 20

8 Figure 2: Example of subsequent successful cut attempt directly across drill collar connection. Page 8 of 20

9 4 Assembly of the Drill Collar Severing Tool 4.1 Safety Procedures JRC Drill Collar Severing Tools are shipped disassembled to allow for preferable transportation methods. Upon delivery to the end user destination, the DCST can be assembled in preparation for deployment into the well. WARNING Refer to and apply the procedures listed in the Recommended Practices for Oilfield Explosives Safety; API Recommended Practice 67 (RP67) before assembling or using this product. BE SURE YOU HAVE READ AND THOROUGHLY UNDERSTAND ALL SAFETY AND ASSEMBLY PROCEDURES BEFORE BEGINNING ANY ASSEMBLY. BEFORE PROCEEDING WITH EXPLOSIVES ASSEMBLY, ENSURE THAT THE WORKING AREA IS CLEAN AND SUITABLE FOR WORKING WITH EXPLOSIVES AND THAT ANY SOURCES OF IGNITION ARE REMOVED. Ensure all required materials are identified and on hand before proceeding with handling of the explosive components. Quantity and shape of explosive components in the kit is dependent on DCST size. The DCST may use a Resistorized detonator, which reduces the possibility of accidental firing by stray current, or a Top Fire, RED detonator; that provides additional safety enhancements when compared to conventional Resistorized detonators. All previously established safety rules and regulations should be maintained during the assembly of explosives. 4.2 Required Materials Item No. Description Part No. 1 Approved Blasters Multimeter Set of Allen Wrench Standard Sizes, 1/16 to 3/ Silicone Grease, DC-4, for O-Rings Shunt Plug Protective Holder Loading Tool Table 2: Required Assembly Tools List. Page 9 of 20

10 Tool OD Explosive Pellets HMX (Rated for 400F for 1 hr) HNS (Rated for 400F for 1 hr) MDF Assembly Hardware Kit Pressure Rating (PSI) Accessories (Select parts according to pressure requirements) DCST Adapter Extension Mandrel Firing Head Assembly Red Adapter (if required) 1-3/ ,000 20, / ,000 20, ,000 20, / ,000 20, / , (For RED, order separately) Not Required if using Table 2b: Required Hardware and Explosive Material List. Page 10 of 20

11 4.3 DCST Assembly Note: Refer to Drawings D (Fig.3), D (Fig.4) and Table 4 in Section Open boxes containing the Explosive Pellets (item 15.1) and two Cartridge Assemblies (15.2). Carefully un-wrap them and ensure that they are all in good condition and that you have the proper number of pellets to assemble the tool, see Table 4 in appendix 1. Divide the pellets into two equal groups; set both groups of pellets aside Remove MDF Assembly (14) from container. Remove protective tube from booster end. Carefully straighten the MDF cord Place half the pellets over the steel tube of the MDF allowing them to bottom out against the base of the MDF Place cartridges over the MDF tube with the small diameters facing each other (see Detail C on drawing D ) CAUTION To ensure proper performance of Jet Research Center s Drill Collar Severing Tool, be careful to place the same number of Explosive Pellets on each side of the Cartridge Assemblies Place the remaining pellets on the MDF tube. Make sure there are an equal number of pellets on each side of the cartridges Slide MDF Assembly tube through the center hole of the end clamp. Hand-tighten the Set Screw (7) to secure the end clamp to the tube. At this time the explosive column should be tightly held (with no play or movement) between the base of the MDF and the end clamp. (Detail B, Drawing D ) CAUTION Use extreme care when bending the cord to insert the booster. A sharp bend or break will destroy the MDF Assembly and cause a misfire Carefully bend the cord of the MDF to an approximate 3/8 inch diameter arc and insert the booster into the offset hole of the end clamp. Gently tighten the Set Screw (8) to hold the booster in place against the end clamp. Do not over tighten the set screw that holds the booster. Only a slight resistance needs to be felt to ensure that the booster remains in place. (Detail B, Drawing D ) Remove the Carrier Tube Assembly (1) from its carton Place the Spacer Spring (9) in the bottom of the carrier tube. Page 11 of 20

12 Carefully place MDF Sleeve (6) (Not required for 1-3/8 DCST) over top of MDF. Slowly lower sleeve into place until bottoming out on top of the first pellet. (Detail A, Drawing D ) With booster end first, insert the assembled explosive column into the carrier tube allowing it to bottom out against the spacer spring Install greased O-Ring(s) (3) on DCST Adapter (2). Insert the adapter into the loaded carrier tube by using Loading Tool (18). NOTE Select the correct adapter according to the pressure rating requirement of the operation. See table 2b Position and tighten the first two (2) Cap Screws (4). Remove the Loading Tool and insert remaining Cap Screws Install proper RED Adapter (if running RED Top Fire) into the DCST Adapter as required by detonator (reference Table 2b) The Explosive Assembly is now complete; set it aside until Electrical Assembly has been connected to the wireline; being careful not to drop or damage it in handling. Page 12 of 20

13 5. Arming and Deployment Procedures with Electric Detonators The term SAFE when used in this document is referring to a combination of actions that are designed to render the initiating system incapable of sending power to the electric detonator. These actions typically involve the shorting of the mono-conductor wireline conductor to ground via a power resistor (for multi-conductor the conductors are connected to one another and ground via power resistors); a key system which prevents the initiating system from connecting power to the electric wireline; and disconnecting power to the initiating system. The key is held outside the unit and visible until the explosive assembly is safely 200 ft (70 m) below ground level or the sea bed; or the cutter and detonator have been removed and returned to storage. The term Radio Silence is used to refer to the combination of actions which involves the shutting down of radio frequency transmissions within 1000 feet (305 m); the shutting down and isolating of electric welding equipment and active cathodic protection. The Drill Collar Severing Tool may use a resistorized detonator, which reduces the possibility of accidental firing by stray current, or a Top Fire RED detonator; that provides additional safety enhancements when compared to conventional resistorized detonators. Note that each detonator requires the use of a different adapter sub (item 17). All previously established safety rules and regulations should be maintained during the assembly of explosives. WARNING CCL SHOULD BE CHECKED OUT PRIOR TO OFF-LOADING EXPLOSIVE ASSEMBLIES. TURN OFF ALL RIG RADIOS, ARC WELDERS AND CATHODIC PROTECTION DEVICES BEFORE ASSEMBLING. BE SURE CABLE IS IN SHORT OR SAFE POSITION AND PERFORATING UNIT S POWER PLANTS ARE TURNED OFF. MEASURE STRAY VOLTAGES BETWEEN PERFORATING UNIT TO GROUND, RIG TO GROUND AND WELLHEAD TO GROUND, ENSURING NO STRAY VOLTAGES ARE PRESENT. PLACE A GROUNDED LOOP BETWEEN PERFORATING UNIT, RIG, AND WELLHEAD. Note: Refer to Drawing D and Table 4 in Section Ensure all required materials are identified and on hand before proceeding but keep the explosive items in safe storage until after the safety precautions are in place. Ensure that the wireline has been put into SAFE ; and that Radio Silence (not required if using RED) and all other safety procedures previously stated are in place before handling the explosive components. 5.2 Check the insulation and continuity of the firing head (19) and the extension mandrels (10). Refer to Table 3 below for appropriate parts. Page 13 of 20

14 Tool OD Pressure Rating (PSI) Hardware (Select parts according to pressure requirements) Extension Mandrel Firing Head Assembly RED Adapter (Required for RED Top Fire only) 1-3/8 15,000 20, /4 15,000 20, ,000 20, /8 15,000 20, /8 26, Not Required if using Table 3: Electrical hardware components. 5.3 Check o-rings (size 214) on all parts listed, making sure there are no cuts, nicks or scratches, install and replace as necessary. Lubricate o-rings and male threads only with a thin coating of clean downhole grease. 5.4 Make up the firing head to the extension mandrels. The extension mandrels are used to protect the running tools from the detonation shock. 5.5 Make up the firing head and extension mandrels to the running tools, making sure the firing head or CCL is made up to the electric wireline cable. Check fire and CCL function. Correct all problems before proceeding and recheck until correct. 5.6 Ensure that cable is in the SAFE position. Ensure a stray voltage and current survey has been performed and grounding lines are attached. Ensure Radio Silence is in place. Clear the assembly and arming area of non-essential personnel. 5.7 Check the firing circuit for the presence of stray voltage with a blasters multimeter in the volts position, between the lower contact and the body of the extension mandrel; first in the DC and then in the AC voltage position. Ensure that no voltage is present between the conductor and ground. Page 14 of 20

15 5.8 Remove the firing head and extension mandrel from the tool string. Install the shunt plug (16) into the top of the firing head. 5.9 Attach the detonator assembly (13) to the end of the extension mandrel by pushing the boot of the detonator assembly onto the end of the extension mandrel. Wrap the ground wire clockwise, looking from the lower end, into the o-ring groove above the boot. Push the o-ring (the o-ring size 020 is included with the detonator assembly) up into the groove ensuring that the end and approximately 2 inches (50 mm) of ground wire is pressed between the o-ring and the mandrel. (Note if using RED, that no ground wire is present as ground is made from barrel spring on body of detonator to the adapter when installed) Remove the tape and/or label and the temporary shunt wire from the detonator assembly If running RED, Install the appropriate adapter (11) for the detonator assembly being used. Refer to Table 3 for appropriate parts Make up the protective holder (17), hand tight, to the adapter, extension mandrel and detonator assembly. Wrench tighten the firing head, extension mandrel and adapter. The shunt plug and protective holder remain hand tight Remove the shunt plug. WARNING DO NOT USE AN OHM-METER! USE AN APPROVED BLASTERS MULTIMETER ONLY Check the firing head, extension mandrel, detonator assembly and adapter for electrical continuity between the top contact and the body of the firing head using a blasters multimeter in the 200 ohm position. The meter should read the resistance of the detonator assembly, typically between 49 and 61 Ohms for the resistorized detonator. Follow specific procedures for measuring continuity with RED With the protective holder still in position, make up the firing head, extension mandrel, detonator, adapter and protective holder assembly to the tool string wrench tight. The detonator is now connected to the firing circuit. The firing circuit must remain in SHORT and SAFE position Remove the protective holder from the adapter, extension mandrel and detonator assembly Make up the DCST explosive assembly to the adapter, extension mandrel and detonator assembly and tighten with a strap wrench. Page 15 of 20

16 5.18 Measure and record the distance from the center of the DCST assembly to the measure point of the tool string; typically the CCL. Also record the part numbers and date codes of the explosive components used in the assembly The DCST assembly is now ready to be run into the pipe. The safety procedures must be maintained until the assembly has been ran below ground level: typically 200 feet (70 m) below ground on land or 200 feet (70 m) below the seabed offshore After Attempting to make the cut; even if there are good indications that the DCST functioned; it is still necessary to go back into SAFE and Radio Silence when coming out of the hole while still 200 feet (70 m) below ground level on land or 200 feet (70 m) below the seabed offshore. Check that the grounding lines are still in place and clear the disarming and disassembly area of non-essential personnel. The safety precautions must remain in force until the explosives responsible person has seen that the cutter functioned and has confirmed that the cutter is no longer a potential explosive hazard. If the cutter did not function it must be disassembled and disarmed before the safety procedures are lifted. The disarming and disassembly procedure follows. Page 16 of 20

17 6. Disarming and Disassembly Procedures with Electric Detonators In the event of having to disarm and disassemble the DCST use the following procedure. If the DCST was run in the well but was unable to detonate it is imperative to use these procedures to remove the cutter and detonator assembly before attempting to perform any investigation and testing to find the problem. If the DCST is run into a well and returned to surface without detonating JRC normally recommends the replacement of all explosive components and o-ring seals. JRC always recommends the replacement of all explosive components and o-ring seals if the cutter has been exposed to temperatures or pressures significantly above ambient conditions. 6.1 The same safety procedures applied while assembling and arming the cutter apply for disarming and disassembly. While the cutter is still deeper than 200 feet (70 m) below the ground level on land or 200 feet (70 m) below the sea bed offshore; ensure that cable is in the SAFE position; grounding lines are attached; If required Radio Silence is in place; and that the disassembly and disarming area is clear of non-essential personnel. WARNING BE AWARE OF POTENTIAL TRAPPED PRESSURE WHEN BREAKING CONNECTIONS ON THE TOOLSTRING ASSEMBLY. 6.2 Remove the DCST from the adapter (11), while monitoring the disassembly for indications of trapped pressure. 6.3 Install the protective holder (17) over the adapter (11), extension mandrel (10) and detonator assembly (13). 6.4 Lay the DCST explosive assembly safely aside while disarming the detonator. 6.5 Disconnect the firing head (19) and extension mandrel, with detonator assembly adapter and protective holder attached, from the tool string and install the shunt plug (16) into the top of the firing head. 6.6 Remove the protective holder and adapter from the extension mandrel. 6.7 Disassemble the detonator assembly from the extension mandrel and re-shunt with appropriate wire. 6.8 Return the detonator with associated labeling to its original packaging and label appropriately for further use or disposal and store appropriately. 6.9 Disassemble the DCST assembly and return its contents to its original packaging with appropriate labeling and store appropriately. Page 17 of 20

18 7. Parts List and Assembly Diagrams Item Description 1 3/8" Qty 1 3/4" Qty 2" Qty 2 5/8" Qty 2-1/8" HP Qty Hardware Kit, consiting of: Carrier Tube Assy A DCST Adapter O-Ring Cap Screw 1/4-20 UNC-2A X End Clamp (Alum Washer) MDF Sleeve N/A Cap Screw 1/4-20 UNC-2A X Set Screw 6-32 UNC-2A X N/A N/A N/A N/A 8-32 UNC-2A X.188 N/A Spacer Spring A Extension Mandrel Assy Firing Head Assembly Not Included Not Included Not Included Not Included Explosive Items 13A Detonator - RED Top Fire B HT Resitorized Detonator D MDF Assembly Explosive Kit, consisting of: Pellets (HMX) (28) (44) (64) (110) (64) 15.2 Cartridges (HMX) (2) (2) (2) (2) (2) 15A Explosive Kit, consisting of: A Pellets (HNS) (28) (44) (64) (110) (64) 15.2A Cartridges (HNS) (2) (2) (2) (2) (2) Required Equipment (must be ordered seperately) 11A Adapter for RED (w/ O-Ring) Use item 20 to replace 12 O-Ring for Adapter DCST Adapter 16 Shunt Plug Protective Holder Loading Tool Firing Head Assembly in kit (19) /8" HP DCST Adapter for RED N/A N/A N/A N/A HP Accessories (For applications in excess of 15,000 PSI up to 20,000 PSI) 2B DCST Adapter in kit (2A) B Extension Mandrel 1-1/2" N/A Parts in kit,rated for 26,00K Extension Mandrel 1-3/8" N/A N/A N/A PSI 11B Adapter for RED Table 4. Drill Collar Severing Tools Parts List Page 18 of 20

19 Figure 3: DCST Assembly Drawing Page 19 of 20

20 Figure 4: 2-1/8 HP DCST Assembly Drawing Page 20 of 20