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    Presentation ESP Grounding

    Uploaded by

    wilzy74
    1. The document discusses methods for protecting oilfield equipment from lightning damage, including tank batteries, electric submersible pumps (ESPs), and their associated electrical equipment. 2. Key protection methods include installing lightning rods and charge transfer systems to safely direct lightning strikes and installing transient voltage surge suppressors (TVSS) on wellheads, junction boxes, and other electrical connections to divert damaging voltage surges to ground. 3. Proper grounding techniques like installing ground grids, wires, and service posts are also described to ensure equipment is connected to an effective earth ground and lightning current paths.

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    Attribution Non-Commercial (BY-NC)
    Download as PDF, TXT or read online from Scribd

    Presentation ESP Grounding

    Uploaded by

    wilzy74
    611 views60 pages
    1. The document discusses methods for protecting oilfield equipment from lightning damage, including tank batteries, electric submersible pumps (ESPs), and their associated electrical equipment. 2. Key protection methods include installing lightning rods and charge transfer systems to safely direct lightning strikes and installing transient voltage surge suppressors (TVSS) on wellheads, junction boxes, and other electrical connections to divert damaging voltage surges to ground. 3. Proper grounding techniques like installing ground grids, wires, and service posts are also described to ensure equipment is connected to an effective earth ground and lightning current paths.

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    1. The document discusses methods for protecting oilfield equipment from lightning damage, including tank batteries, electric submersible pumps (ESPs), and their associated electrical equipment. 2. Key protection methods include installing lightning rods and charge transfer systems to safely direct lightning strikes and installing transient voltage surge suppressors (TVSS) on wellheads, junction boxes, and other electrical connections to divert damaging voltage surges to ground. 3. Proper grounding techniques like installing ground grids, wires, and service posts are also described to ensure equipment is connected to an effective earth ground and lightning current paths.

    Copyright:

    Attribution Non-Commercial (BY-NC)
    Download as PDF, TXT or read online from Scribd
    Download as pdf or txt
    611 views60 pages

    Presentation ESP Grounding

    Uploaded by

    wilzy74
    1. The document discusses methods for protecting oilfield equipment from lightning damage, including tank batteries, electric submersible pumps (ESPs), and their associated electrical equipment. 2. Key protection methods include installing lightning rods and charge transfer systems to safely direct lightning strikes and installing transient voltage surge suppressors (TVSS) on wellheads, junction boxes, and other electrical connections to divert damaging voltage surges to ground. 3. Proper grounding techniques like installing ground grids, wires, and service posts are also described to ensure equipment is connected to an effective earth ground and lightning current paths.

    Copyright:

    Attribution Non-Commercial (BY-NC)
    Download as PDF, TXT or read online from Scribd
    Download as pdf or txt
    of 60

    Stopping Oilfield Lightning Damage

    You can not stop lightning!

    True. But you can stop the damage it does! An Engineering Approach

    Oil Production Priorities


    Tank Batteries, does NFPA 780 really apply? Disposal pump motors and controls Electric Submersible Pumps, ESP, does API RP11S really apply? ESP Variable Frequency Drives Pumping unit motors and controls

    Tank Battery Protection


    Strike Collection with Franklin rods (Also called lightning rods, air terminals, etc.), catenary wires, early streamer emitters National Fire Protection Association (NFPA) and Lightning Protection Institute Strike Avoidance Charge Transfer Systems

    Electrical Equipment Protection


    4-wire Transient Voltage Surge Suppressors (TVSS) Wellhead Grounding Junction box TVSS mounting Ungrounded transformer windings Separate Ground Wires Power distribution with an overhead neutral, OHN, or shield wire

    Tank Battery Protection

    E 1000 Barrels ach, 15'-5" dia, 30' high Fiber glass, gun barrel, w sep. ater

    CLVSD 125 H SWD P M otor

    500 H SWD P M otor catw alk Disposal Well 150' E ast

    Rolling Sphere Calculation


    74 foot diameter

    K nockouts, steel 10' dia x 20' long & 10' dia x 15' long

    Vertical G Separator as 3' dia x 12' high

    Oil Storage 300 Barrel 12' dia, 15'-5" high Steel E ach

    catwalk

    Scale 1" = 20'

    North

    Problems
    Presence of explosive gases Fluids that develop an electrical charge Attracting lightning and getting it safely into the ground without igniting gases Does NFPA 780 really apply?

    Solution
    Prevent lightning from striking tank batteries Charge Transfer Systems - Explanation Demonstration Details !! The devil is in the.. MIL TFP 41

    Leader Delayed by _ Space Charge _

    _ _ ___ _ _ _ _ _
    Competing Leaders Continue toward Earth

    ++ + + + + + + + + + + + ++ + + + + ++ + + + +

    + + +

    + +

    _ _ _ _ ___ _ _ _ _ _
    Winning the Competition

    + + + + + + + + + ++ ++ + + ++ +

    ++

    Grounding Making Contact with Charge beneath the tanks and in the tanks
    Ground rods, loops, grids Chemical grounds Thief hatch ground rods Carbon C Veil Bonding

    Electrical Equipment Protection

    Metal Oxide Varistors (MOV) TVSS (SPD) Basic Element


    Varistor = variable resistor Resistance changes with voltage Convert lightning energy into heat, if properly installed Analogous to Back Pressure Relief Valve

    + Volts Current or Flow

    Current

    M OV Pressure or Volts X
    Pressure or Voltage Limit Maximum Allowable Working Pressure or Insulation Puncture Voltage

    TVSS Modes and Wires


    A B A G B

    delta
    Three Mode
    C A B

    A G

    Four Mode

    Six Mode

    3-wire SPD (TVSS), No Ground

    Effect of Long Ground Wire


    V oltage Im pulse P ressure Im pulse P ressure R elief V alve MV O

    Large voltage drop along ground w ire inductance

    Large pressure drop in long, sm diam all eter discharge pipe.

    Valve bypass into a small diameter discharge tube equivalent to a TVSS with long ground wire and high ground resistance.

    Wellhead Grounding
    Getting to Infinite Ground water table? A ground rod thousands of feet long Ground resistance less than ONE ohm Can the wellhead be damage by lightning? National Electric Code (NEC) requirement Opus 250, No. .-112M Corrosion? AC No, Cathodic protection evaluation CPET. Coexistence Surge and Cathodic protection

    Wellhead Electrical Connection


    Ground Clamps loose, loose wire, paint and corrosion, few contact points, shock, workover crew removal and replacement? Cad Weld Great connection, RR signal lights & substation ground grids, can not be removed to check wires, welding around natural gas? Service Post Grounding

    Service Post Wellhead Grounding

    Welded Bolt and Ground Lug

    Lightning Arresters
    H1 H2 H1 H2 H1 H2

    X1

    X2

    X1

    X2

    X1

    X2

    Transformers Power System Ground Switchboard W ellhead

    Junction or Vent Box

    G roundw ire E surface line arth E Cable SP arm groundw or ire

    Pole Butt Plate or W rap Additional ground rods as needed Ground connection point

    10,000 V

    Inductance of pole ground wire

    Inductance of pole to wellhead ground wire

    0V

    Voltage at switchboard Butt wrap ground resistance

    Voltage at wellhead W ellhead ground resistance

    Lightning at arrester common

    Infinite Ground

    Ground Wire and Wellhead Voltages


    9000

    8000

    7000

    g
    6000

    a b c
    5000
    Volts

    Switchboard Mounted TVSS

    4000

    3000
    .5 Ohm 5 Ohm 10 Ohm 20 Ohm

    2000

    1000

    Vent Box a b c Mounted TVSS g


    3.E-06 Time 4.E-06 5.E-06 6.E-06 7.E-06

    0 0.E+00

    1.E-06

    2.E-06

    MOV Volt Amp Characteristics


    Current

    -MOV volts +MOV volts

    Volts

    Backwards

    Lightning voltage onbutt w rap

    G M OV volts

    C + M OV volts _

    Separate Bonded Ground Wires


    An Improperly Installed TVSS Can Cause ESP Damage
    Indian Basin and Tatum, NM

    ShieldWire (OverheadNeutral, OH N)

    Backward Through:

    Lightning Arresters
    H 1 H 2 H 1 H 2 H 1 H 2

    Lightning Arresters TVSS or Secondary Lightning Arresters Switchboard Mounted TVSS

    X1 X2

    X1 X2

    X1 X2

    Transform ers

    Reda Cable

    TVSS

    Preferred Submersible Pump Grounding for Lightning Protection


    1. Ground wires should be green THHN insulated, #2AW stranded copper to minimize G breakage and corrosion. 2. For safety ESP cable armor must be connected to the ESP System Ground with #8 AW solid copper wire as shown. Between the switchboard and poles it should be G isolated from the Power System Ground. 3. Power System and ESP System ground wires should be run no closer than 6" apart to avoid sideflash. Pole ground wire and wellhead are the only permissible connections on the Power System ground wire. 4. ESP System Ground wires should connect to the ground lug on the TVSS at the junction box. The small green TVSS wire should ground the junction box internally. 5. At the junction box armors should not come in contact with each other or the metal box to minimize ground loop interference. Switchboard W ellhead ESP System Ground, Blue Tape Junction or Vent Box
    E surface line arth E Cable SP Lightning Arresters
    H1 H2 H1 H2 H1 H2

    X1

    X2

    X1 X2

    X1

    X2

    Transformers

    a b c g

    Pro-M oDr TVSS

    Power System Ground, W hite Tape

    6. A service post (Burndy K2C23B1 or Penn-Union SCS-4A1) screwed into a tapped hole between bolts in the lower flange is the recommended wellhead grounding method. A "hot work" permit will be required if natural gas is present. Connection at the lower flange should eliminate the need for ground wire removal during a workover.

    Pole Butt Plate or W rap Additional ground rods as needed Ground connection point

    Simplified Submersible Pump Grounding for Lightning Protection


    1. Transformer windings to the ESP must be ungrounded. 2. Power System Ground connects to the switchboard and cable armors as shown. 3. Power System Ground goes directly to the wellhead without contacting the junction box. 4. TVSS and Power System ground wires should be green THHN insulated, #2 AW stranded G copper to minimize breakage and corrosion and isolated from each other to avoid sideflash. 5. At the junction box armors should not come in contact with each other or the metal box. 6. TVSS Ground wire should connect to the ground lug on the TVSS at the junction box. The small green TVSS wire grounds the junction box internally. 7. A service post (Burndy K2C23B1 or Penn-Union SCS-4A1) screwed into a tapped hole between bolts in the lower flange is the recommended wellhead grounding method. A "hot work" permit will be required if natural gas is present. Connection at the lower flange eliminates the need for ground wire removal during a workover. Switchboard W ellhead TVSS Ground Blue Tape
    a b c

    Lightning Arresters
    H1 H2 H1 H2 H1 H2

    X1

    X2

    X1 X2

    X1

    X2

    Transformers (secondary windings ungrounded)

    Arm or ground

    Junction or Vent Box


    E surface line arth

    Pro-M oDr TVSS Cable arm or grounds E Cable SP

    Power System Ground - W hite & Red Tape

    Pole Butt Plate or W rap Additional ground rods as needed Ground connection point

    Preferred Submersible Pump Lightning Protection Grounding for Variable Speed Drives

    Lightning Arresters
    H1 H2 H1 H2
    X1 X2 X1 X2

    H1

    H2

    X1

    X2

    T ransformers Power System Ground

    Disconnect

    TVSS1

    1. Ground wires should be green THHN insulated, #2AW stranded copper to minimize G breakage and corrosion. 2. Power system ground wire should not connect directly to the drive through conduit or the disconnect. It should go directly to the wellhead. This is critical to preventing TVSS1 from damaging the VSD and ESP when lightning strikes. Disconnect, VSD and step-up transformers are still bonded via the ESP system ground wire. 3. 480V power into VSD should be ungrounded. 4. For safety ESP cable armor must be connected to the ESP System Ground or TVSS Ground with #8 AW solid copper wire as shown. Between the switchboard and G poles it should be isolated from the Power System Ground. 5. Power System, ESP System and TVSS ground wires should be isolated from each other to avoid sideflash 6. TVSS Ground wire should connect to the ground lug on the side of TVSS2 at the junction box. The small green TVSS wire should ground the junction box internally. 7. At the junction box armors should not come in contact with each other or the metal box to minimize ground loop interference. 8. A service post (Burndy K2C23B1 or Penn-Union SCS-4A1) screwed into a tapped hole between bolts in the lower flange is the recommended wellhead grounding method. A "hot work" permit will be required if natural gas is present. Connection at the lower flange should eliminate the need for ground wire removal during a workover. 9. If drive is trailer mounted junction box should W ellhead be fiber glass for electrical isolation
    arm ground or w ire Step-U Transform p er

    Variable Speed Drive

    Junction or Vent Box


    E Cable SP TVSS groundblue tape

    TVSS2

    or
    Earthsurface line

    Pole Butt Plate or Wrap Additional ground rods as needed

    arm groundw or ire Pow systemground er w tape hite E systemground SP redtape

    Ground connection point

    Ungrounded Transformer Windings


    The preferred way for 80 years Continuous oil production through first insulation fault Grounding will damage cable or motor on first fault so that ESP must be pulled Improved lightning protection Grounding is to LA common Perfectly Safe

    Junction Box Mounting


    Shortest ground wire to the wellhead On load side of switchboard contactor so overload protection will be activated if TVSS fails Wellhead connects directly to the housing of the downhole ESP motor

    Priority 2 Protection of Disposal Pump Motor and Control


    A Wellhead ground is normally not available Connect to ground loop around tank battery If possible separate lightning arrester ground wire from motor and control ground wire

    480V, 3 phase

    Power System Ground and Lightning Arrester Common

    Control box

    TVSS Motor

    Wellhead
    Y X

    Earth surface Z

    Ground wires Ground rod (Optional)

    Summary
    Charge Transfer Systems can provide improved tank battery protection. Reliability has been over 99% for 40,00 service years Properly designed and installed TVSS can prevent almost all equipment damage if: 4-wire TVSS are used grounded to wellhead junction box mounting ungrounded transformer windings separate ground wires

    Lightning Damage can be Stopped!


    Science and Engineering will Ultimately Prevail
    Equipment Repair and Replacement can be Reduced

    Lost Production can be Minimized

    A Bad Day in the Neighborhood

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