Trenching and Conduit

60 Pages·2012·1.14 MB·English

22.00 GENERAL
GENERAL INFORMATION 22.00-100
22.01 TRENCHING
MINIMUM CABLE COVER AND SEPARATION 22.01-101
TRENCH CONFIGURATIONS 22.01-102A
TRENCH CONFIGURATIONS 22.01-102B
TRENCH, BACKFILL AND COMPACTION REQUIREMENTS 22.01-104
MARKING TAPE - BURIED ELECTRICAL LINE 22.01-106
22.02 DIRECTIONAL BORING
DIRECTIONAL BORING 22.02-100
22.03 CONDUIT USE
USES FOR CONDUIT 22.03-100
CONDUIT USE BY TYPE 22.03-102
22.04 CONDUIT AND CONDUIT ACCESSORIES
(RIGID) PVC SCHEDULE 40 CONDUIT 22.04-100
PVC COUPLING - STANDARD - WITH CENTER STOP 22.04-102
PVC SLIP COUPLING - NO CENTER STOP 22.04-104
PVC MALE TERMINAL ADAPTER 22.04-106
LOCKNUT 22.04-108
PVC FEMALE ADAPTER 22.04-110
PVC PLUG / END CAP 22.04-112
PVC END BELL 22.04-114
PVC REDUCERS 22.04-116
PVC BENDS - 90 DEGREES - SCHEDULE 40 22.04-118
PVC BENDS - 45 DEGREES - SCHEDULE 40 22.04-120
PVC BENDS - 22-1/2 DEGREES - SCHEDULE 40 22.04-122
PVC SERVICE RISER 22.04-124
PVC VENTED RISERS 22.04-128
CONDUIT SUPPORT STRAPS - WOOD POLE MOUNT 22.04-130
CELLULAR CORE PVC CONDUIT 22.04-134
HIGH DENSITY POLYETHYLENE (HDPE) CONDUIT 22.04-136
HDPE CONDUIT COUPLINGS 22.04-138
STEEL CONDUIT 22.04-140
FIBERGLASS CONDUIT 22.04-142
22.05 CONDUIT INSTALLATION AND REPAIR
CUTTING AND JOINING PVC CONDUIT 22.05-100
INSTALL PREBENTS 22.05-102
JOINING 6" PVC TO 7" POLYETHYLENE PIPE 22.05-104
PVC CONDUIT AND CIC INSTALLATION PROCEDURE 22.05-106
REPAIRING EXISTING PVC CONDUIT WHEN CONDUIT CONTAINS CABLE 22.05-108
REPAIRING EXISTING PVC CONDUIT WHEN CONDUIT DOES NOT CONTAIN CABLE 22.05-110
3 DEC DEM DEP DEF
SECTION 22 - TRENCHING, DIRECTIONAL BORING,
2
1 CONDUIT & DUCT BANK X
0 12/31/15 KATIGBAK EANES ADCOCK TABLE OF CONTENTS 22.00-00A
REVISED BY CK'D APPR.
22.06 DUCT BANKS
DUCT BANK DESIGN CRITERIA 22.06-100A
DUCT BANK DESIGN CRITERIA 22.06-100B
DUCT BANK CONFIGURATIONS TWO WIDE 22.06-102
DUCT BANK CONFIGURATIONS THREE WIDE 22.06-104
DUCT BANK CONFIGURATIONS STREET LIGHTING 22.06-106
DUCT BANK CONFIGURATIONS JOINT USE 22.06-108
DUCT BANK SPACERS 22.06-110
DUCT BANK GROUNDING 22.06-112A
DUCT BANK GROUNDING 22.06-112B
ESTIMATING CONCRETE 22.06-114
DUCT BANK INSTALLATION INSTRUCTIONS 22.06-116A
DUCT BANK INSTALLATION INSTRUCTIONS 22.06-116B
DUCT BANK FIELD BENDS 22.06-118
DUCT BANK JOINTS 22.06-120
DUCT BANK INSPECTION CHECKLIST 22.06-124
22.07 CABLE PULLING
CABLE PULLING - GENERAL INFORMATION 22.07-100A
CABLE PULLING - GENERAL INFORMATION 22.07-100B
RECOMMENDED CONDUIT FILL 600V AL AND CU CABLES 22.07-102
RECOMMENDED CONDUIT FILL PRIMARY CABLES 22.07-106
CABLE PULLING LUBRICANTS 22.07-108
PULLING GRIPS FOR UNDERGROUND CABLES 22.07-112A
PULLING GRIPS FOR UNDERGROUND CABLES 22.07-112B
CABLE PULLING SOFTWARE DSTAR CABLE PULLING ASSISTANT (CPA) 22.07-114
3 DEC DEM DEP DEF
SECTION 22 - TRENCHING, DIRECTIONAL BORING,
2
1 CONDUIT & DUCT BANK X
0 12/31/15 KATIGBAK EANES ADCOCK TABLE OF CONTENTS 22.00-00B
REVISED BY CK'D APPR.
DUKE ENERGY IS A "DIRECT BURIED" UTILITY. THIS MEANS THE COMPANY TYPICALLY DIRECTLY BURIES ALL
600 VOLT AND MEDIUM VOLTAGE PRIMARY CABLE IN THE GROUND WITHOUT THE USE OF CONDUIT.
ONE MAJOR EXCEPTION IS THE FACILITIES INSTALLED IN OHIO AND KENTUCKY. CABLES IN THOSE STATES ARE
TYPICALLY INSTALLED IN CONDUIT, MUCH OF WHICH IS PROVIDED BY THE CUSTOMER. THIS IS DONE TO
COMPLY WITH STATE REGULATIONS.
OTHER EXAMPLES OF SITUATIONS WHERE CABLE MAY BE INSTALLED IN CONDUIT OR AN EMPTY CONDUIT
INSTALLED FOR FUTURE USE IS PROVIDED ON DWG. 22.03-100 (USES FOR CONDUIT).
CONDUIT IS NOT REQUIRED FOR DIRECTIONAL BORE INSTALLATIONS EXCEPT WHEN MANDATED BY THE
P ERMITTING AUTHORITY.

REFER TO SECTION 36 FOR THE FOLLOWING INFORMATION:

CLEARANCES
JOINT USE TRENCH DESIGNS
TRENCHING NEAR STRUCTURES
TRENCHING/DIRECTIONAL BORING NEAR TREES
3 DEC DEM DEP DEF
2
1 GENERAL INFORMATION X X X X
0 12/31/15 FLETCHER EANES ADCOCK 22.00-100
REVISED BY CK'D APPR.
TABLE 1: MINIMUM CABLE COVER
CABLE OR APPLICATION MINIMUM COVER SPECIFIC NOTES JOINT TRENCH
SECONDARY / SERVICE 30" SEE NOTES 2 AND 3
(cid:51)(cid:53)(cid:44)(cid:48)(cid:36)(cid:53)(cid:60)(cid:3)(cid:11)(cid:20)(cid:145)(cid:3)(cid:50)(cid:53)(cid:3)(cid:22)(cid:145)(cid:12) 36" SEE NOTES 2 AND 3 SEE SECTION 36 X
ROAD CROSSINGS (ANY VOLTAGE) 36" SEE NOTE 5 FOR JOINT TRENCH
RAILROAD CROSSINGS (ANY VOLTAGE) PERMIT SPECIFIC SEE NOTE 5 CONSTRUCTION
PARKING LOT CROSSINGS (ANY VOLTAGE) 36" SEE NOTES 2, 3 AND 5
TABLE 2: REQUIRED MINIMUM SEPARATION BETWEEN CABLES WHEN SEPARATION
IS TO BE OBTAINED HORIZONTALLY (CABLES ARE BURIED AT THE SAME DEPTH)
COLUMN 1 MINIMUM HORIZONTAL SEPARATION FROM CABLES IN COLUMN 1
PRIMARY, 200A PRIMARY, 200A
PRIMARY, (cid:11)(cid:20)(cid:145)(cid:3)(cid:50)(cid:53)(cid:3)(cid:22)(cid:145)(cid:12)(cid:3)(cid:58)(cid:43)(cid:40)(cid:49) (cid:11)(cid:20)(cid:145)(cid:3)(cid:50)(cid:53)(cid:3)(cid:22)(cid:145)(cid:12)(cid:3)(cid:58)(cid:43)(cid:40)(cid:49)
SECONDARY/ FEEDER
CABLE 200A BOTH CABLES BOTH CABLES
SERVICE (>200A)
(cid:11)(cid:20)(cid:145)(cid:3)(cid:50)(cid:53)(cid:3)(cid:22)(cid:145)(cid:12) ARE NOT PART OF ARE PART OF
THE SAME LOOP THE SAME LOOP
SECONDARY /
RANDOM LAY RANDOM LAY 36"
SERVICE X
PRIMARY, 200A
RANDOM LAY RANDOM LAY* 36" 36"
(cid:11)(cid:20)(cid:145)(cid:3)(cid:50)(cid:53)(cid:3)(cid:22)(cid:145)(cid:12)
FEEDER (>200A) 36" 36" 36"
*SEE NOTE 7 FOR ADDITIONAL DEC REQUIREMENT
TABLE 3: REQUIRED MINIMUM SEPARATION BETWEEN CABLES WHEN SEPARATION
IS TO BE OBTAINED VERTICALLY (CABLES ARE BURIED AT THE DIFFERENT DEPTHS)
COLUMN 1 MINIMUM VERTICAL SEPARATION FROM CABLES IN COLUMN 1
PRIMARY, 200A PRIMARY, 200A
PRIMARY, (cid:11)(cid:20)(cid:145)(cid:3)(cid:50)(cid:53)(cid:3)(cid:22)(cid:145)(cid:12)(cid:3)(cid:58)(cid:43)(cid:40)(cid:49) (cid:11)(cid:20)(cid:145)(cid:3)(cid:50)(cid:53)(cid:3)(cid:22)(cid:145)(cid:12)(cid:3)(cid:58)(cid:43)(cid:40)(cid:49)
SECONDARY/ FEEDER
CABLE 200A BOTH CABLES BOTH CABLES
SERVICE (>200A)
(cid:11)(cid:20)(cid:145)(cid:3)(cid:50)(cid:53)(cid:3)(cid:22)(cid:145)(cid:12) ARE NOT PART OF ARE PART OF
THE SAME LOOP THE SAME LOOP
SECONDARY /
RANDOM LAY RANDOM LAY 12"
SERVICE X
PRIMARY, 200A
RANDOM LAY RANDOM LAY* 12" 12"
(cid:11)(cid:20)(cid:145)(cid:3)(cid:50)(cid:53)(cid:3)(cid:22)(cid:145)(cid:12)
FEEDER (>200A) 12" 12" SEE NOTE 6
*SEE NOTE 7 FOR ADDITIONAL DEC REQUIREMENT
NOTES:
1. MINIMUM SEPARATION BETWEEN CABLES MAY BE OBTAINED EITHER HORIZONTALLY OR VERTICALLY.
2. IF REQUIRED MINIMUM DEPTH CANNOT BE OBTAINED, INSTALL CABLE IN SCHEDULE 40 OR GREATER
CONDUIT WITH A MINIMUM OF TWO (2) INCHES OF CONCRETE ABOVE AND BESIDE THE CONDUIT AND A
MINIMUM OF SIX (6) INCHES OF COVER.
3. RISER CONDUIT BENDS AND BRIDGE TRANSITIONS ARE EXCEPTIONS TO THE MINIMUM COVER REQUIREMENT.
4. REFER TO SECTION 36 FOR JOINT TRENCH INFORMATION AND CONSTRUCTION DETAILS.
5. IF PERMIT IS REQUIRED, MINIMUM DEPTH WILL BE PERMIT SPECIFIC RATHER THAN THE DEPTH LISTED, BUT
NEVER LESS THAN NESC REQUIREMENTS.
6. FEEDERS (>200A) MUST BE SEPARATED HORIZONTALLY BY 36". VERTICAL SEPARATION ONLY IS NOT AN OPTION.
(cid:26)(cid:17)(cid:3)(cid:39)(cid:40)(cid:38)(cid:3)(cid:53)(cid:40)(cid:52)(cid:56)(cid:44)(cid:53)(cid:40)(cid:54)(cid:3)(cid:36)(cid:3)(cid:48)(cid:44)(cid:49)(cid:44)(cid:48)(cid:56)(cid:48)(cid:3)(cid:50)(cid:41)(cid:3)(cid:20)(cid:21)(cid:5)(cid:3)(cid:57)(cid:40)(cid:53)(cid:55)(cid:44)(cid:38)(cid:36)(cid:47)(cid:3)(cid:54)(cid:40)(cid:51)(cid:36)(cid:53)(cid:36)(cid:55)(cid:44)(cid:50)(cid:49)(cid:3)(cid:37)(cid:40)(cid:55)(cid:58)(cid:40)(cid:40)(cid:49)(cid:3)(cid:20)(cid:145)(cid:3)(cid:36)(cid:49)(cid:39)(cid:3)(cid:22)(cid:145)(cid:3)(cid:38)(cid:36)(cid:37)(cid:47)(cid:40)(cid:54)(cid:3)(cid:36)(cid:49)(cid:39)(cid:3)(cid:37)(cid:40)(cid:55)(cid:58)(cid:40)(cid:40)(cid:49)

(cid:54)(cid:40)(cid:38)(cid:50)(cid:49)(cid:39)(cid:36)(cid:53)(cid:60)(cid:18)(cid:54)(cid:40)(cid:53)(cid:57)(cid:44)(cid:38)(cid:40)(cid:3)(cid:36)(cid:49)(cid:39)(cid:3)(cid:22)(cid:145)(cid:3)(cid:38)(cid:36)(cid:37)(cid:47)(cid:40)(cid:54)(cid:17)

8. TABLES 2 AND 3 SPECIFY APPLICATIONS THAT REQUIRE SEPARATION BETWEEN CABLES. ALL OTHER
APPLICATIONS WILL USE "RANDOM LAY" WHICH MEANS CABLES MAY BE PLACED INTO A TRENCH WITH NO
REQUIRED SEPARATION.
9. EITHER ONE WIDE TRENCH OR TWO NARROW TRENCHES MAY BE USED, BASED ON
ECONOMICS, TO OBTAIN REQUIRED HORIZONTAL SEPARATION.
3 DEC DEM DEP DEF
2
1 MINIMUM CABLE COVER AND SEPARATION X X X X
0 12/31/15 FLETCHER EANES ADCOCK 22.01-101
REVISED BY CK'D APPR.
FINAL GRADE FINAL GRADE
FIGURE 1 FIGURE 2
30"
36"
12"
SECONDARY/ SERVICE WITH SECONDARY/ SERVICE WITH
200A SINGLE-PHASE PRIMARY 200A THREE-PHASE PRIMARY
FINAL GRADE OPTIONAL METHODS FINAL GRADE
FIGURE 3 FIGURE 4
30"
36"
6"
12" 12"
SECONDARY/ SERVICE WITH SECONDARY/ SERVICE WITH
TWO 200A SINGLE-PHASE PRIMARIES TWO 200A SINGLE-PHASE PRIMARIES
THAT ARE BOTH PART OF THE SAME LOOP THAT ARE BOTH PART OF THE SAME LOOP
FINAL GRADE
FIGURE 5
36"
12"
ONE 200A SINGLE-PHASE PRIMARY WITH
ONE 200A THREE-PHASE PRIMARY
NOTES:

1 . SEE DWG. 22.01-102B FOR NOTES.
2. THESE CONFIGURATIONS ARE REQUIRED FOR DEC ONLY. THEY ARE OPTIONAL FOR ALL
OTHER LOCATIONS.
3. CABLES AT THE SAME DEPTH CAN BE RANDOM LAY.
3 DEC DEM DEP DEF
2
1 TRENCH CONFIGURATIONS X X X X
0 12/31/15 FLETCHER EANES ADCOCK 22.01-102A
REVISED BY CK'D APPR.
FINAL GRADE FINAL GRADE
FIGURE 2
FIGURE 1
36" 36"
36" 36"
TWO 200A THREE-PHASE PRIMARIES
TWO SINGLE-PHASE PRIMARY CABLES
BOTH PART OF THE SAME LOOP OR
BOTH PART OF THE SAME LOOP 200A THREE-PHASE WITH A FEEDER (>200A)
OR TWO FEEDERS (>200A)
FINAL GRADE FINAL GRADE
FIGURE 3 FIGURE 4
36" 36"
36" 36"
SINGLE-PHASE WITH A FEEDER (>200A) SECONDARY/SERVICE WITH A FEEDER (>200A)
FINAL GRADE
FIGURE 5
PRIMARY:
36" MIN. COVER
SECONDARY/SERVICE:
30" MIN. COVER
RANDOM LAY
NOTES:
1. THE TRENCH CONFIGURATIONS SHOWN ON DWG. 22.01-102A AND THIS DRAWING WITH A SPECIFIED
SEPARATION BETWEEN CABLES ARE THE ONLY APPLICATIONS THAT REQUIRE SEPARATION BETWEEN CABLES.
SEPARATION MAY BE OBTAINED EITHER VERTICALLY AS SHOWN ON DWG. 22.01-102A OR HORIZONTALLY AS
SHOWN ON THIS DRAWING. ALL OTHER APPLICATIONS WILL USE THE RANDOM LAY CONFIGURATION SHOWN
ABOVE IN FIGURE 5. RANDOM LAY ALLOWS CABLES TO BE PLACED INTO A TRENCH WITH NO REQUIRED
SEPARATION.
2. EITHER ONE WIDE TRENCH OR TWO NARROW TRENCHES MAY BE USED BASED ON ECONOMICS TO OBTAIN
REQUIRED HORIZONTAL CABLE SEPARATION.
3. IF REQUIRED CABLE SEPARATION CANNOT BE OBTAINED DUE TO SPACE LIMITATIONS, PROVIDE MECHANICAL
PROTECTION BY INSTALLING THE CABLE IN SCHEDULE 40 OR GREATER PVC CONDUIT WITH A MINIMUM OF TWO
(2) INCHES OF CONCRETE ABOVE AND BESIDE THE CONDUIT.
4. JOINT TRENCH CONFIGURATIONS ARE PROVIDED IN SECTION 35: UNDERGROUND
CLEARANCES AND JOINT USE.
3 DEC DEM DEP DEF
2
1 TRENCH CONFIGURATIONS X X X X
0 12/31/15 FLETCHER EANES ADCOCK 22.01-102B
REVISED BY CK'D APPR.
TRENCH
RIGHTS-OF-WAY/EASEMENTS AND STREETS SHALL BE CLEARED AND TO FINAL GRADE BEFORE TRENCHING BEGINS.
STANDARD TRENCH DEPTHS ARE SHOWN ON DWGS. 21.01-102A AND 21.01-102B. DUKE ENERGY REQUIRES A
MINIMUM COVER OF THIRTY (30) INCHES FOR 600V CABLE AND THIRTY-SIX (36) INCHES FOR MEDIUM VOLTAGE
(PRIMARY) CABLE.
REFER TO DWG. 22.01-101 WHEN IT IS NOT POSSIBLE TO OBTAIN THE ABOVE DEPTHS.
THE BOTTOM OF THE TRENCH SHALL BE SMOOTH, UNDISTURBED EARTH, WELL-TAMPED CLEAN BACKFILL OR
SAND, FREE OF ROCKS, DEBRIS OR ROOTS. WHEN EXCAVATION IS IN ROCK OR ROCKY SOIL, CABLE, CONDUITS
O R CABLE-IN-CONDUIT SHALL BE LAID ON A WELL-TAMPED LAYER OF CLEAN BACKFILL AT LEAST FOUR (4) INCHES
T HICK.
SHORING
THE PERFORMANCE OF EXCAVATION WORK INCLUDING TRENCHING, SLOPING, BENCHING, AND SHORING MUST,
A T MINIMUM, MEET THE REQUIREMENTS OF OSHA 1926 SUBPART P AND ANY LOCAL JURISDICTIONAL
R EQUIREMENTS.
REFER TO THE TRENCHING AND EXCAVATIONS SECTION OF THE HEALTH AND SAFETY HANDBOOK FOR DUKE
ENERGY REQUIREMENTS.
BACKFILL
BACKFILL WITHIN SIX (6) INCHES OF THE CABLE OR CONDUIT SHALL BE FREE OF ROCK OR ANY MATERIAL THAT
MAY DAMAGE THE CABLE OR CONDUIT. THE REMAINING BACKFILL SHOULD BE FREE OF MATERIAL GREATER THAN
FOUR (4) INCHES IN MAXIMUM DIMENSION.
COMPACTION
BACKFILL MUST BE ADEQUATELY COMPACTED. BACKFILL SHALL BE COMPACTED SUCH THAT WASHING AND
SETTLING OF THE TRENCH SURFACE WILL NOT OCCUR. ADDITIONAL BUILDUP OF THE BACKFILL MAY BE
NECESSARY TO PREVENT SETTLING. FINAL SURFACE COMPACTION SHALL LIMIT THE AMOUNT OF SETTLING TO
1/2" OR LESS. ANY REWORK OF THE TRENCH IS THE RESPONSIBILITY OF THE INSTALLER.
MACHINE COMPACTION SHALL NOT BE USED WITHIN SIX (6) INCHES OF THE CABLE OR CONDUIT.
WHEN MACHINE COMPACTION IS REQUIRED, TRENCHES SHALL BE BACKFILLED BY ALTERNATING FILL AND
TAMPING THE FIRST 12 INCHES AND IN EACH ADDITIONAL 12 INCH INCREMENT.
COMPACTION FOR STREET CROSSINGS MUST COMPLY WITH LOCAL JURISDICTIONAL REQUIREMENTS.
EXTREME SLOPES OR OTHER UNUSUAL FIELD CONDITIONS MAY REQUIRE ADDITIONAL MECHANICAL TAMPING
OR SODDING AT THE DISCRETION OF THE FIELD ENGINEER OR COMPANY DESIGNATED REPRESENTATIVE.
3 DEC DEM DEP DEF
2
1 TRENCH, BACKFILL AND COMPACTION REQUIREMENTS X X X X
0 12/31/15 FLETCHER EANES ADCOCK 22.01-104
REVISED BY CK'D APPR.
BACKFILL
36"
TYPICAL
MARKING TAPE - "CAUTION ELECTRIC LINE BURIED BELOW"
12" MIN.
24" MAX.
BACKFILL
PRIMARY CABLE
REGION COMPATIBLE UNIT ITEM NUMBER
DEC 0354165, 2352, 2352INF 354165
DEM - 50086491
DEP - 21149505
DEF - 21149505
NOTES:
1. THE USE OF MARKING TAPE DOES NOT GUARANTEE A REDUCTION IN DIG-INS. AS A RESULT, IT IS NOT
RECOMMENDED FOR REGULAR USAGE. HOWEVER, MARKING TAPE IS AVAILABLE FOR INSTALLATION AT THE
REQUEST OF A CUSTOMER OR GOVERNMENT AGENCY. NORMAL CHARGING PRACTICES WILL APPLY.
2. CONSIDERATION SHOULD BE GIVEN TO PLACING CABLES IN CONDUIT, CONCRETE ENCASED CONDUIT, OR
DUCT BANK IN ORDER TO REDUCE DIG-INS.
3. MARKING TAPE IS A 3" (6" IN DEM) WIDE RED TAPE WITH "CAUTION ELECTRIC LINE BURIED BELOW" PRINTED
REPEATEDLY ALONG ITS LENGTH AND IS SUPPLIED IN 1,000 FOOT ROLLS.
4. INSTALL MARKING TAPE 12" MINIMUM TO 24" MAXIMUM ABOVE THE PRIMARY CABLE.
3 DEC DEM DEP DEF
2
1 MARKING TAPE - BURIED ELECTRICAL LINE X X X X
0 12/31/15 FLETCHER EANES ADCOCK 22.01-106
REVISED BY CK'D APPR.
OVERVIEW
DIRECTIONAL BORING IS A STEERABLE TRENCHLESS METHOD OF INSTALLING UNDERGROUND CABLES,
CONDUITS AND PIPES ALONG A PRESCRIBED PATH BY USING A SURFACE LAUNCHED DRILLING RIG. THIS METHOD
HAS MINIMAL IMPACT ON THE SURROUNDING AREA. IT IS TYPICALLY USED WHEN TRENCHING OR EXCAVATING
IS NOT PRACTICAL (I.E. UNDER CONCRETE OR PAVEMENT) OR WHEN CUSTOMER SATISFACTION (I.E. CABLE
REPLACEMENT) IS A MAJOR CONCERN.
PROCESS
THE DRILLING RIG, POSITIONED AT THE STARTING POINT, PUSHES THE DRILLING HEAD INTO THE SOIL AND
PUMPS FLUID TO THE HEAD. THE FLUID, TYPICALLY BENTONITE, IS PUMPED AT HIGH PRESSURE IN FRONT OF
THE DRILLING HEAD IN THE DIRECTION THE OPERATOR WANTS THE HEAD TO TRAVEL. THIS FLUID SOFTENS THE
SOIL IN THAT DIRECTION AND THE HEAD MOVES IN THAT DIRECTION SINCE IT IS THE PATH OF LEAST
RESISTANCE. THAT IS HOW THE OPERATOR STEERS THE DRILLING HEAD ALONG THE ROUTE TO THE RECEIVING
POINT AT THE END OF THE BORE. THE FLUID ALSO COOLS THE HEAD AND HELPS TO REMOVE DISLODGED SOIL.
(cid:55)(cid:43)(cid:40)(cid:3)(cid:39)(cid:53)(cid:44)(cid:47)(cid:47)(cid:44)(cid:49)(cid:42)(cid:3)(cid:43)(cid:40)(cid:36)(cid:39)(cid:3)(cid:44)(cid:54)(cid:3)(cid:38)(cid:50)(cid:49)(cid:49)(cid:40)(cid:38)(cid:55)(cid:40)(cid:39)(cid:3)(cid:55)(cid:50)(cid:3)(cid:43)(cid:44)(cid:42)(cid:43)(cid:3)(cid:54)(cid:55)(cid:53)(cid:40)(cid:49)(cid:42)(cid:55)(cid:43)(cid:3)(cid:54)(cid:55)(cid:40)(cid:40)(cid:47)(cid:3)(cid:179)(cid:53)(cid:50)(cid:39)(cid:54)(cid:180)(cid:3)(cid:55)(cid:43)(cid:36)(cid:55)(cid:3)(cid:36)(cid:53)(cid:40)(cid:3)(cid:36)(cid:51)(cid:51)(cid:53)(cid:50)(cid:59)(cid:44)(cid:48)(cid:36)(cid:55)(cid:40)(cid:47)(cid:60)(cid:3)(cid:20)(cid:19)(cid:3)(cid:55)(cid:50)(cid:3)(cid:20)(cid:24)
FEET LONG. THE DRILLING CREW CONTINUES TO ADD ADDITIONAL RODS UNTIL THE DRILLING HEAD REACHES
THE END OF THE BORE.
ONCE THE INITIAL BORE IS COMPLETE, THE OPERATOR PULLS A REAMING HEAD BACK THROUGH THE BORE
TOWARD THE DRILLING RIG. AT THE SAME TIME, CABLE, CONDUIT OR PIPE IS PULLED BACK THROUGH THE
BORE.
DUKE ENERGY REQUIREMENT
DIRECTIONAL DRILLING EQUIPMENT CAN APPLY EXCESSIVE TENSION WHICH CAN SERIOUSLY DAMAGE CABLE
BEING PULLED THROUGH A BORE.
FOR THE ABOVE REASON, DUKE ENERGY REQUIRES DIRECTIONAL DRILLING CONTRACTORS TO UTILIZE A
TENSION LIMITING DEVICE WHEN PULLING CABLE THROUGH A BORE. THIS CAN BE A PIECE OF BARE #6 AWG
SOLID COPPER WIRE FOR 1/0 AWG MEDIUM VOLTAGE CABLE. TENSION LIMITING ATTACHMENTS (TYPICALLY
BREAK-AWAY DEVICES) ARE AVAILABLE FROM VARIOUS TOOL MANUFACTURERS FOR USE WITH OTHER CABLES.
MAXIMUM ALLOWABLE PULLING TENSIONS FOR ALL MEDIUM VOLTAGE CABLES ARE PROVIDED IN SECTION 23
(UNDERGROUND CABLES).
DIRECTIONAL BORING NEAR TREES
SEE SECTION 36, UNDERGROUND CLEARANCES AND JOINT USE, FOR DETAILS.
3 DEC DEM DEP DEF
2
1 DIRECTIONAL BORING X X X X
0 12/31/15 FLETCHER EANES ADCOCK 22.02-100
REVISED BY CK'D APPR.
DUKE ENERGY TYPICALLY DIRECT BURIES ALL 600 VOLT AND MEDIUM VOLTAGE PRIMARY CABLE IN THE GROUND
WITHOUT THE USE OF CONDUIT. HOWEVER, LISTED BELOW ARE SOME EXAMPLES OF SITUATIONS WHERE CABLE
MAY BE INSTALLED IN CONDUIT OR SPARE (EMPTY) CONDUITS INSTALLED.
FUTURE MAINTENANCE (REPLACEMENT) CONSIDERATIONS
APPLICATIONS WHERE FUTURE REPLACEMENT OF CABLE WOULD NOT BE POSSIBLE USING TRENCHING OR
DIRECTIONAL BORING METHODS. DIRECTIONAL BORING LIMITATIONS ARE AS FOLLOWS:
BORE WOULD BE LONGER THAN MAXIMUM CABLE FOOTAGE ON A REEL
BORE LENGTH EXCEEDS EQUIPMENT CAPABILITIES (TYPICALLY 500' BUT CONSULT WITH CONTRACTOR)
EXCESSIVE CABLE PULLING TENSIONS THROUGH CONDUIT WOULD BE ENCOUNTERED
NOT ADEQUATE "GREEN" SPACE FOR BORE PITS
PROJECT TIMING
CROSSINGS UNDER PAVEMENT WHERE CABLE CANNOT BE INSTALLED PRIOR TO THE PAVEMENT. EFFORT SHOULD
BE MADE TO INSTALL CABLE IF TIMING AND FIELD CONDITIONS ALLOW.
CUSTOMER REQUEST
THE DUKE ENERGY STANDARD IS TO PROVIDE DIRECT-BURIED UNDERGROUND CABLES. CUSTOMER REQUESTS
FOR A CONDUIT INSTALLATION SHOULD BE EVALUATED ON A CASE-BY-CASE BASIS AND WILL REQUIRE
MANAGEMENT APPROVAL. THE CUSTOMER WILL BE RESPONSIBLE FOR PAYING ALL ADDITIONAL COSTS
ASSOCIATED WITH THE REQUEST (I.E. CONDUIT, PULL BOXES, SPLICES, PULLING LABOR, ETC.)
SPECIFIC REGULATIONS
RAILROAD AND GAS TRANSMISSION CROSSINGS
CROSSING OTHER UTILITIES WHEN CODE CLEARANCES CANNOT BE MET
REQUIRED BY DOT OR OTHER GOVERNMENTAL AGENCIES
SUBSTATION EXITS TO THE TERMINATION POINT
FUTURE GROWTH
CONDUIT MAY BE NECESSARY TO ACCOMMODATE FUTURE PROJECT EXPANSIONS OR LOAD GROWTH. FOR
LONGER TERM PROJECTS, AN ECONOMIC ANALYSIS SHOULD BE PERFORMED TO DETERMINE THE BEST OPTION
(I.E. INSTALL CONDUIT NOW VS BORE IN THE FUTURE).
SHALLOW INSTALLATIONS
CABLE SHALL BE INSTALLED IN CONCRETE-ENCASED CONDUIT WHEN MINIMUM CABLE COVER REQUIREMENTS
CANNOT BE MET. SEE DWG. 22.01-101 FOR DETAILS.
RADIAL PRIMARY FEEDS
WHEN THE MAJORITY OF THE CABLE SUPPLYING A SINGLE RADIAL-FED TRANSFORMER IS UNDER PAVEMENT
OR CONCRETE, THE CABLE CAN BE INSTALLED IN CONDUIT OR AN EMPTY CONDUIT CAN BE INSTALLED ALONG
THE ENTIRE ROUTE.
CABLE MAY ALSO BE INSTALLED IN CONDUIT AND EMPTY CONDUIT INSTALLED FOR FUTURE CABLE INSTALLATION
WHEN IT IS SERVING A "SHORT-TERM RADIALLY-FED TRANSFORMER" (THE LOOP WILL BE COMPLETED AT SOME
POINT IN THE FUTURE) WHEN IT WILL NOT BE POSSIBLE TO TRENCH AROUND THE TRANSFORMER OR
DIRECTIONALLY BORE IN THE AREA TO INSTALL THE FUTURE CABLE.
DUCT BANK
MANY CITIES REQUIRE UTILITIES TO INSTALL THEIR FACILITIES UNDERGROUND IN DESIGNATED INNER-CITY
AREAS. CABLE WOULD BE INSTALLED IN CONCRETE ENCASED DUCT BANK IN THESE DESIGNATED AREAS. SEE
THE DUCT BANK PORTION OF THIS SECTION FOR DETAILS.
THERE MAY ALSO BE HEAVILY CONGESTED URBAN AREAS OUTSIDE OF THE INNER-CITY AREA WHERE EITHER
DUKE ENERGY CHOOSES OR THE CITY MANDATES FOR UTILITIES TO INSTALL FACILITIES UNDERGROUND. CABLE
WOULD BE INSTALLED IN CONCRETE ENCASED DUCT BANK IN THESE DESIGNATED AREAS. SEE SUBSECTION 22.06
FOR DETAILS.
DIRECTIONAL BORING
WHEN CABLE PLACEMENT HAS TO BE DEEPER THAN 48"
IF ANY OF THE ABOVE APPLICATIONS APPLY
MISCELLANEOUS
ROCKY SOIL
ROUGH TERRAIN
3 DEC DEM DEP DEF
2
1 USES FOR CONDUIT X X X X
0 12/31/15 FLETCHER EANES ADCOCK 22.03-100
REVISED BY CK'D APPR.