IADC Drilling Manual Part 9 ppt

Any attempt to improve rope service by increasing the ton-mile goalshould not be made until one entire drilling line requiring no long cuts has been used following this particularprogram

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M-34 International Association of Drilling Contractors

The most used practice is to use left-hand reeving and locate the deadline anchor to the left of the derrick vee Inselecting the best of the various possible methods for reeving casing or drilling lines, the following basic factorsshould be considered

1 Minimum fleet angle from the drawworks drum to the first sheave of the crown bloc, and from the crown blocksheaves to the traveling block sheaves

2 Proper balancing of crown and traveling blocks

3 Convenience in changing from smaller to larger number of lines, or from larger to smaller number of lines

4 Locating of deadline on monkey board side for convenience and safety of derrickman

5 Location of deadline anchor, and its influence upon the maximum rated static hook load of derrick

Figure M2-4 Reeving Diagram For 12-Line String-Up With 7-Sheave Crown Block And 6-Sheave Traveling Block; Left Hand

2 Work Encountered in Reeving System:

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International Association of Drilling Contractors

By utilizing mechanical advantage of the pulley, you are not decreasing the work done Work done is the loadmultiplied by the distance moved When the load is hoisted, each of the lines shortens by the distance of the hoist.However, the last line or fast line, coming onto the drum, must take up all the extra line This is, of course, thedistance the load moves times the number of lines strung Inasmuch as the load on this line is the weight lit~eddivided by the number of lines, then the work done by the hoist is the same as the work required to raise the load

3 Line Speed:

Since the movement of the drilling line, being wound or unwound on the drum is greater than the movement of thetraveling block, the speed with which it moves is also greater Thus if the traveling block is being lowered at therate of 10 ft per second, or 10 fps, in a 6-line system, the line is paying off the drum at 60 fps or 3600 fpm Themaximum recommended speed for movement of wire ropes through the sheaves is 4000 fpm If the block of an 8-line system were moving at 10 fps, the line speed would exceed the recommended rate

4 Determining Maximum Pull:

The fast line during hoisting has a load greater than the total weight being lifted divided by the number of parts ofline The load is increased by the friction of the sheave bearings and the bending of the line around the sheaves.Starting at the deadline sheave, each successive line has, during hoisting, an extra load on it caused by the "sum" ofthe frictional loads from all previous rotating sheaves Since the fast line experiences the accumulation of frictionalforces from all rotating sheaves, its load is the greatest and it should be used when calculating design factors.The fast line load can be calculated by the following formula:

L = W x Ks x (K-1)/(Kn -1)

Where:

L = fast line load, lbs

W = total weight lifted, lbs

K = friction coefficient Roller bearing Sheaves = 1.04

n = number of parts of line

*s = number of rotating sheaves

*NOTE: Deadline crown sheave does not rotate during hoisting so, for most rotary rigs, s = n

EXAMPLE:

500,000 lb load; 10 = line string up w/ 1-1/2" EIPS; Drilling line friction coefficient = 1.04

What is the lead line load and design factor?

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Fast line loads and design factors for various hook loads with 6, 8, 10, and 12 parts of line are shown in Table 6

M2-Table M2-6 Fast Line Load and Design Factors for Various Hook Loads with 6, 8, 10 and 12 Parts of Line (AIlCalculations Based Upon New 6X19 IWRC Wire Rope) Table based on the Extra Improved Plow and ImprovedPlow with independent wire rope cores

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Table M2-6 Fast Line Load Design Factors

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M3 Factors Affecting Service Life Of Wire Rope

Following are some of the factors that have a direct effect upon rotary drilling line service Although they areelemental, they are critical

1 Mast or Derrick Height

The mast or derrick height will vary from approximately 65' to 185' or more Governs the total amount of rotaryline in the stringup, and determines whether "doubles," "triples" or "quadruples" of drill pipe will be handled duringtrips

2 Crown Blocks Sheaves

Sheave diameters should be large enough to minimize the bending fatigue which occurs on a rotary line Worngrooves will not properly support the rotary line and worn bearings set up undue wear on both the sheaves and theline

3 Traveling Block Sheaves

The same conditions concerning the sheaves apply here as with the Crown Block In addition, the traveling blockmust be of sufficient weight to give tight spooling on the drum as the block assembly is being raised or lowered,when going into and coming out of the hole

4 Draw Works Drum

The diameter and length of drum is important A drum of small diameter and length requires more drum wraps toraise the blocks This leads to more layers of rope on the drum, and therefore, more "cross-over" wear points Agrooved drum increases wire line service by supporting the rotary line and giving a tighter wrap The condition ofthe drum clutch and brake greatly affects line life If these are not properly adjusted, the resulting jerking andshock loads must be borne by the rotary line

5 Type of String-Up - 6, 8, 10 or 12 Lines

The type of String-Up will govern the load each part of line must carry, determines the total line in the String-Up,and also determines the length of time wear points must remain in the system

6 Dead Line Anchor or Clamp

The size, type and condition of the anchor has a direct effect on the rotary line If it is too small, or otherwisedistorts the line, it may form a "dog-leg" in the line which will set up a stress point This stress point will result inundue wear and early fatigue, necessitating a long cut to remove it from the system

7 Wire Line Stabilizer and Turn-Back Rollers

The Wire Line Stabilizer and Turn-Back Rollers help extend the life of the wire line The wire line stabilizerrelieves vibration or "whip" on the "fast" line The turn-back rollers help relieve shock at the "cross-over" points onthe drum and prevent line piling up at the drum flanges Weight box type stabilizers are considered far superior asfar as drum spooling is concerned Deadline stabilizers reduce vibration in the deadline adjacent to the deadlineanchor and deadline sheave

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11 Size of Drill Pipe

Determines the total load when figuring the ton mile service per round trip, and in making connections

12 Size and Number of Drill Collars

The size and number of Drill Collars is one of the variable factors in determining the total excess weight whenfiguring ton-mile service per round trip

13 Drill Stem Tests

Drill Stem Tests mean extra round trips over and above those necessary to change bits

16 "Twist Offs" and "Fishing" Jobs

"Twist Offs" and "Fishing" Jobs often mean several extra round trips to completely remove the "fish" or obstructionbefore normal drilling can be resumed

When we take these elemental factors into consideration it is then apparent why we must "tailor" a rotary lineservice program to each individual rig Refer to Figure M2-1, and Figure M2-2

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M4 Ton Mile Calculations

A Introduction

In the early 1940's a drilling contractor would have purchased only enough rotary drilling line to string up hisreeving system Depending upon the height of his derrick and the number of parts of line to be used, lengths wouldvary from 650 to 1,750 feet In working the line, heavy wear would occur in a few localized sections: where therope makes contact with the traveling block sheaves, and where the rope makes contact with the crown blocksheaves when the slips are pulled going in or coming out of the hole, and on the drum where each wrap of ropecrosses over the rope on the layer below Broken wires at these points of critical wear would result in the retire-ment of the entire string up, even though the remainder of the rope was in good condition

Today, purchasing longer lengths of drilling line, and periodically slipping new rope into the system while cutting offold line at the drum end, shifts the rope through these critical wear areas and distributes the wear more uniformlyalong the length of the rope See Figure M4-1

Figure M4-1 Wire Line Wear Points

If too much wire rope is cut off too frequently, there will be an obvious waste of usable drilling line, which willresult in higher than necessary rig operating costs However, if the rope is moved through the reeving system tooslowly, sooner or later some section of the drilling line will become worn and damaged to such an extent that therewill be a danger of failure, injury to personnel, damage to equipment and expensive downtime At the very least, itwill be necessary to make a "long cut" to eliminate some broken wires

For these reasons, it is important that the drilling line be cut off at the proper rate The purpose of this SimplifiedCut-Off Practice is to give the drilling contractor a method for keeping track of the amount of work done by thedrilling line, and a systematic procedure for making cuts of the appropriate length at the appropriate time Theobjective is to obtain maximum rope service without jeopardizing the safety of the rig operation

In conjunction with the record keeping required for the cut-off procedure, daily visual inspection of the drilling lineshould be made for broken wires and any other rope damage It must be remembered that in all cases, visualinspection of the wire rope by the drilling contractor must take precedence over any predetermined calculations

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The only complicated part of a cut-off procedure is the determination of how much work has been done by thewire rope Methods such as counting the number of wells drilled or keeping track of days between cuts are notaccurate because the loads change with depth and with different drilling conditions The various operations per-formed (drilling, coring, fishing, setting casing, etc.) subject the rope to different amounts of wear

For an accurate record of the amount of work done by a drilling line, it is necessary to calculate the weight beingLifted and the distance it is raised and lowered In engineering terms, work is measured in foot-pounds On adrilling rig the loads and distances are so great that we use "ton-miles." One ton-mile equals 10,560,000 foot-pounds, and is equivalent to lifting 2,000 pounds a distance of 5,280 feet

To simplify the calculation of ton-miles, a Ton-Mile Indicator has been developed The following pages provideexamples of how this Indicator is used to determine the number of ton-miles of work done by the drilling line forvarious operations on the rig Please refer to Table M4-1 and Table M4-2 as you go through the examples

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International Association of Drilling Contractors T

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Table M4-2 Wire Rope Indicator - Ton-Mile per Round Trip - 4-1/2" 16.6 ppf in mud

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These tables are taken from the Ton-Mile Indicator developed by Union Wire Rope Indicators are available for any type or size of drill pipe in both mud and air drilling Contact a Union Wire Rope representative for the Indicator(s) you require.

B Examples Of Ton-mile Calculations

1) Example No 1: Round Trip Ton-Miles

a) Situation: At a depth of 11,000 feet, a round trip is made to change the bit

Drill Pipe = 4-1/2", 16.6 ppf

Drill Collars = ten, 7-1/4", 119.2 ppf

Traveling block assembly weight (hook, elevators, traveling block) = 27,000 lbs

Drilling Fluid = mud

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Weight factor due to collars = 13,000 lbs

2 Determine Total Weight Factor: Add together Weight Factor due to Collars and weight of Traveling Blockassembly

Traveling Block Assembly Weight = 27,000 lbs + Weight Factor due to Collars = 13,000 lbs

Total Weight Factor = 40,000 lbs

3 Determine Ton-Miles Per Round Trip: On Table M4-2, locate depth and read round trip ton-miles in appropriatecolumn

Round Trip = 337 Ton-Miles

* Note: For laying down drill pipe at the end of well, figure one-half of round trip ton-miles for drill string in tion

ques-2) Example No 2: Drilling Ton-Miles

a) Situation: Drilling continues from a depth of 11,000 feet to a depth of 12,000 feet

Drill Collars = ten, 7-1/4", 119.2 ppf

Traveling block assembly weight = 27,000 lbs

Drilling fluid = mud

b) Solution:

Ton-Miles for drilling from one depth to another equals 3 times the difference in round trip ton-miles for the twodepths

Total Weight Factor:

1 Determine Ton-Miles for a Round Trip Where Drilling Stopped:

Locate depth of 12,000'; Read under the 40,000 lb column that Ton-Miles = 384 T-M

2 Determine Ton-Miles for a Round Trip Where Drilling Started:

Locate depth of 11,000'; Read under 40,000 lb column that Ton-Miles = 337 T-M

3 Calculate the Difference in Round Trip Ton-Miles: 384 - 337 = 47 T-M

4 Calculate Drilling Ton-Miles:

Drilling ton-miles = difference in round trip ton-miles times 3 = 47 x 3 = 141 T-M

Ton-Miles for Drilling from 11,000' to 12,000' = 141 T-M

3) Example No 3: Ton-Miles for Setting Casing

a) Situation: Setting 10-3/4", 40.5 ppf casing from surface to 3,600 feet

Traveling Block Assembly Weight = 20,000 lbs

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b) Solution: The ton-miles of work done in setting casing would be one-half the ton-miles done in making a roundtrip:

if the weight of the casing were the same as the weight of the drill pipe

1 Determine the ratio of casing weight to drill pipe weight: (40.5 ppf)/(16.6 ppf) = 2.44

2 Determine ton-miles for making a round trip with pipe: Locate depth of 3,600 feet

Read under 20,000 lb column No drill collars are used, therefore,

the Total Weight Factor is equal to the traveling block assembly weight only

3 Determine ton-miles for making a round trip with casing:

Multiply by the weight ratio: 2.44 x 46 = 122 T-M

Round trip for casing = 112 T-M ton-miles

4 Determine ton-miles for setting casing:

Divide by 2, since the casing is only set down and not pulled out

(112/2) = 56 T-M Ton-miles; To set the casing = 56 T-M

4) Example No 4: Ton-Miles for a Short Trip

a) Situation: Having drilled to 13,000 feet, a short trip is made back to 9,000 feet to condition the hole

Drill Collars = Twenty, 7-3/4", 138 ppf

Traveling Block Assembly Weight = 20,000 lbs

Drilling Fluid = Mud

b) Solution: The ton-miles of work done in making a short trip

equals round trip ton-miles at the deeper depth minus the round trip ton-miles at the shallower depth

1 Determine ton-miles for a round trip at 13,000 feet:

Locate depth of 13,000 feet On Table M4-2Read under 50,000# column

Round trip ton-miles at 9,000 feet = 284 T-M

2 Determine ton-miles for a round trip at 9,000 feet: On Table M4-2

Locate depth of 9,000 feet, Read under 50,000 lb column

Round trip ton-miles at 9,000 feet = 483 T-M

3 Determine ton-miles for the short trip:

From 483 T-M Subtract 284 T-M = 199 T-M

So, Ton-miles for the short trip = 199 T-M

5) Example No 5: Ton-miles for round trip of mixed drill string

a) Situation: Having drilled to 13,000 feet with a drill string (5" to 9000 ft, 4-1/2" 16.6 ppf below, and 15 jts 7-1/4"DCs @ 138 ppf), a round trip is made:

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Drilling Fluid = Mud; Traveling Block Assembly Weight = 27,000 lbs

b) Solution:

1 Weight Factor due to collars = 23,000 lbs

2 Total Weight Factor = 23,000 + 27,000 = 50,000 lbs

3 Ton-miles for round trips:

Ton-miles for a round trip with the mixed drill string = 502 T-M

6) Example No 6: Ton-Miles for Round Trip with Heavy Wall Drill Pipe

a) Situation: Having drilled to 12,000 feet with the drill string (4-1/2" from surface, then below with 30 jts 4-1/2" 42ppf HWDP, then 20 jts 7-1/4" ppf DCs @ 138 ppf), a round trip is made:

Drilling Fluid = Mud; Traveling Block Assembly Weight = 30,000 lbs

b) Solution: Instead of trying to calculate the heavy-weight pipe as in a mixed drill string, treat it as additional drillcollars

Use the drill collar window on the back of the Union Ton-Mile Indicator

which is closest to the heavy-weight pipe weight, or do the calculations by hand

1 Determine weight factor due to collars: On Table M4-1, locate proper drill collar number and read weight due tocollars under appropriate column Weight factor due to DCs = 30,700 lbs

2 Determine weight factor due to heavy wall drill pipe:

Figure the heavy-weight drill pipe as if they were drill collars On Table M4-1 locate the proper heavy-weight pipenumber and read the weight due to heavy-weight pipe from the window with the closest drill collar weight is 46.7ppf)

An accurate value for Weight Factor due to heavy-weight pipe can also be figured longhand as follows (moreaccurate):

Excess weight per foot = 42.0 - 16.6 = 25.4

Total excess weight = 25.4 x 900' = 22,860 lbs

Buoyed excess weight = 22,860 x 0.85 = 19,431 lbs

1/2 Buoyed excess weight = 19,431/2 = 9,716 lbs

So, the weight factor due to the heavy-weight drill pipe = 9,716 lbs

3 Determine total weight factor:

Traveling block assembly weight = 30,000 lbs

Weight factor due to collars = 30,700 lbs

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Weight factor due to the HWDP = 9,716 lbs

Total weight factor = 70,416 lbs

4 Determine ton-miles per round trip:

Locate depth of 12,000'

Read under 70,000 lb window

Round trip ton-miles = 520 T-M

C Ton-miles Per Foot Cut

The purpose of calculating the amount of work done by the drilling line is to give an accurate method for ing when and how much drilling line to slip through and cut off The objective of spreading the rope wear along thelength of the line can be accomplished best by cutting lengths proportional to the ton-miles of work accumulated.All that is necessary is to maintain a consistent number of ton-miles per foot of rope cut

determin-For a given rope size, any particular rig can get only so many ton-miles of service The key to a successful cut-offprocedure is to spread these ton-miles uniformly by using the optimum ton-mile per foot cut goal A rig which hasbeen able to get about 66,000 T-M out of a 1-3/8" x 5,000' drilling line, may have a string-up of 1,700' for ten parts.The remaining 3,300' available to be cut off should be cut at a rate of one foot for every 20.0 ton-miles (66,000 T-

M )/( 3,300 ft) = 20.0 T-M/ft) The ton-mile goal would be 20.0

The ton-mile goal for any rig with good past performance records can be calculated in the same manner If the rig

is new, or if the records are unavailable, a ton-mile goal can be selected from Table M4-3

Table M4-3 T-M Goal Where Records Are Not Available

Note: Only the drilling line size and the drum diameter are needed to determine a ton-mile goal These are the mostimportant factors that influence ton-mile service on a drilling rig

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D Ton Mile Calculations - Drilling Ton Miles for Top Drive (Drilling with Stands)

Ton mile calculations for other operations tend to be unaffected by the addition of the top drive, with the exception

of the additional traveling equipment weight

Definition of Terms:

WDS = Buoyant weight of drill string (drill pipe and BHA)

M = Weight of traveling equipment

LS = Length of a stand

Drilling Operation Cycle:

1) Drill down length of stand (LS)

2) Raise stand and ream back down full length

3) Set slips and break out at pipe handler

4) Raise traveling equipment; pick up next stand and make up

5)Pick up off slips and begin again

Ton Miles Generated Per Cycle Segment:

If one combines steps 1 through 5, the following applies:

Ton Miles Per Stand Drilled = (LS x (3 WDS + 4 M)/(2000 x 5280)

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M5 Cut-off Program

A Cut-Off Program

Assuming that 1-3/8" drilling line is used on a NATIONAL 130 (30" drum) rig with no past performance records,Table M4-3 gives a suggested ton-mile goal of 19.0 Table M5-1 is the Union Wire Rope Cut-Off Program for a19.0 ton-mile goal

Click Here for Table M5-1 Union Wire Rope Cut-Off Program For 1-3/8" Rotary Drilling Line (Example Only)Other programs are available for the specific goal required for your rig

Tables on M5: Union Wire Rope Cut-Off Program For 1" thru 1-1/2" Rotary Drilling Lines

Note: the program is summarized by the statement: Length to Cut = T-M Since Last Cut % 19.0

So long as the maximum ton-mile accumulation shown on the program is not exceeded, a cut may be made

whenever it is convenient It is only necessary to total the ton-miles accumulated since the last cut and divide by19.0 to determine what length to cut This way the ton-miles per foot cut will always be exactly 19.0, and the wear

on the drilling line will be uniformly spread along its length

For convenience, the calculations have been made for a number of ton-mile accumulations, and are presented intabular form on the program

B Suggestions for Cut-Off Practice

Whatever program is used, it should be followed throughout the life of one entire drilling line If no long cuts arerequired, and it is believed that more service can be obtained from a line, the goal can be raised one ton-mile perfoot cut This procedure should be followed until the optimum goal is found

Avoid accumulating more ton-miles between cuts than the maximum shown on the program for your rig even onthe first cut of a new line

It is best not to run up to the maximum permitted ton-miles each time between making a cut, as some problem onyour rig could prevent a cut being made at the proper time and lead to a ton-mile overrun A better approach is tobounce around on your program, cutting with a new ton-mile accumulation sometimes and alternating with amedium or higher ton-mile accumulations This practice does not waste wire rope because you are always cuttingoff lengths in proportion to the work accumulated

Accurate measurement of the length to cut is very important A steel tape should be used when making thismeasurement

When stringing back from 12 to 10 lines, or from 10 to 8 lines, make a cut of the appropriate length based upon theton-mile accumulation at that time This procedure will shift the critical wear points on the rope following heavyoperations such as setting casing

Keep your wire rope history Sheets current, accurate and complete

Calculate ton-miles for drilling after each round trip Failure to record drilling ton-miles is probably the most

common mistake made in cut-off practice

The best cut-off program is the one with the most consistent ton-mile per foot cut values By staying as close aspossible to the ton-mile goal you will avoid long cuts and maintain the safest, and most economical use of yourrotary drilling line

Daily visual inspection of the drilling line should be made for broken wires and any other rope damage

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Note: in all cases, visual inspection of the wire rope by the drilling contractor must take preference over anypredetermined calculations

C Union Wire Rope Cut-Off Program For Rotary Drilling Line

Tables on M5: Union Wire Rope Cut-Off Program For 1" thru 1-1/2" Rotary Drilling Lines

Cut-Off Program For 1" Rotary Drilling Line

Cut-Off Program For 1" Rotary Drilling Line; Goal of 6.0 T-M/Ft Cut

Table - M5-p2a Wire Rope Cut-off Program, 1" Rotary Drill Line, Goal: 6.0 T-M/ft cut

1 Do not accumulate more than 800 ton-miles between cuts, even on the first cut of a new line

2 So long as less than 800 ton-miles have been accumulated, a cut may be made at anytime it is convenient Todetermine the length to cut, refer to the above table or calculate so that your "ton-miles per foot cut" is constant(length to cut = T-M since last cut % 6.0)

3 This program is based upon a goal of 6.0 Any attempt to improve rope service by increasing the ton-mile goalshould not be made until one entire drilling line (requiring no long cuts) has been used following this particularprogram

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Table - M5-p2b Wire Rope Cut-off Program, 1" Rotary Drill Line, Goal: 7.0 T-M/ft cut

2 So long as less than 1000 ton-miles have been accumulated, a cut may be made anytime it is convenient Todetermine the length to cut, refer to the above table or calculate so that your "ton-miles per foot cut" is constant(length to cut = T-M since last cut % 7.0)

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Table - M5-p3a Wire Rope Cut-off Program, 1" Rotary Drill Line, Goal: 8.0 T-M/ft cut

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Table - M5-p3b Wire Rope Cut-off Program, 1" Rotary Drill Line, Goal: 9.0 T-M/ft cut

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Cut-Off Program For 1-1/8" Rotary Drilling Line

Cut-Off Program For 1-1/8" Rotary Drilling Line; Goal of 9.0 T-M/Ft Cut

Table - M5-p4a Wire Rope Cut-off Program, 1-1/8" Rotary Drill Line, Goal: 9.0 T-M/ft cut

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Table - M5-p4b Wire Rope Cut-off Program, 1-1/8" Rotary Drill Line, Goal: 10.0 T-M/ft cut

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Cut-Off Program For 1-1/4" Rotary Drilling Line; Goal of 15.0 T-M/Ft Cut

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Tiêu đề	IADC Drilling Manual Part 9 ppt
Trường học	International Association of Drilling Contractors
Chuyên ngành	Oil and Gas Drilling
Thể loại	manual
Năm xuất bản	Eleventh Edition

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Số trang	86
Dung lượng	1,01 MB