Pipe measurement, labeling and controls

A combination of systems to measure the length of pipe sections and to label the pipe surface with machine readable labels. The combination also commits to memory the data and specifications read from the label or derived from correlative information already in memory. Summation of pipe joint data and specifications provide overall pipe string data. From the collective pipe string data, the reaction of the string to the input of physical forces can be predicted and evaluated.

This invention pertains to the measurement of the length of pipe joints and 
the automatic labeling of pipe surfaces with related information. 
RELATED PATENTS 
The following issued U.S. patents pertain to art associated with individual 
sub-systems incorporated into the combination of systems utilized in the 
apparatus and method of this invention: U.S. Pat. Nos. 4,224,509 issued 
Sept. 23, 1980; 4,333,006 issued June 1, 1982; 4,417,816 issued Nov. 29, 
1983; 4,427,882 issued Jan. 24, 1984; 4,431,912 issued Feb. 14, 1984; and 
4,459,752 issued July 17, 1984. 
BACKGROUND 
The processes related to drilling and casing earth boreholes are well 
known. Earth boreholes are produced through the use of pipe strings known 
as drill strings. The boreholes, once drilled, are cased with a different 
form of pipe string cemented into the earth. Yet another pipe string is 
commonly suspended inside the casing to conduct fluids produced far below 
to the earth surface. The pipe strings are interrelated in many respects, 
and it is important that drilling and well completion people have the 
lengths of pipe rather accurately measured as an assembly in each case. In 
the past, the measuring art has yielded many errors with serious economic 
and safety consequences. 
At the present time, there are two general classifications of pipe used in 
earth borehole operations, primarily in oil and gas well drilling and oil 
and gas production: 
(1) shouldered pipe joints used in drilling; and 
(2) non-shouldered pipe joints used in casing and in production tubing. 
Shouldered pipe is used in well drilling and added to the drill string 
joint-by-joint as the well is deepened by drilling. During drilling 
activity, the drill string is occasionally removed from the well to change 
drill bits and other components, usually near the bit. During these "round 
trips," the drill string is usually separated in three joint "stands" and 
set back on the rig floor in a vertical stance to await reassembly in 
reverse order, as the drill string is once more assembled into the well to 
resume drilling. 
During the removal phase of the "round trip," the driller and others remain 
alert for any signs of damage on any emerging pipe joint or its 
connections. Any damaged joint will be removed and "laid down," so that it 
will not be later reassembled into the drill string. The total length of 
all such laid down joints must be made up by the addition of new pipe 
joints. The new joints will be pulled up to the rig floor from the pipe 
racks at the rig site. 
From the beginning of the assembly, the pipe joint drawn up to the rig 
floor will be "strapped." This is an act of measuring the 
shoulder-to-shoulder length, usually with a steel measuring tape. The 
driller maintains a pipe tally of all lengths added to the drill string. 
Since there may eventually be in the order of five hundred drill string 
joints and shorter reamers and stabilizers, as well as jars and downhole 
motors, the tally is necessarily large. With the occasional laid down 
joints and new additions, the volumnous tally is often modified. Some of 
these tally changes are interrupted by occasional shift changes of all rig 
floor personnel. Some confusion is inevitable. 
An entire production zone can be erroneously logged in terms of distance 
below the earth surface due to errors in pipe length. Subsequent 
completion operations such as perforating can miss the production zone. To 
reduce this likelihood, considerable expense is incurred in logging wells 
independently of drill strings. 
When non-shouldered pipe is installed in a well, a different set of 
problems arises. Non-shouldered pipe has a variable thread make-up 
responsive to connection geometry and makeup torque applied. The total 
joint length is measured and thread make-up allowance is subtracted. The 
problem of continual round tripping related to the drill string does not 
occur with non-shouldered pipe. 
In addition to the errors cited above, pipe strings suspended in great 
length stretch several feet due to axial strain from load. With drill 
string, drillers use prepared tables to indicate stretch to be expected. 
In drilling, the bit load applied at the bottom changes drill string total 
length. Changes in pressure applied to the drill pipe to force drilling 
fluids to circulate also change pipe length. 
OBJECTS 
It is therefore an object of this invention to provide apparatus and 
methods to measure the length of pipe string components by electromagnetic 
radiation processes and to mark the resulting data on the pipe without 
human transcription of the information. 
It is another object of this invention to provide apparatus and methods to 
measure the length of pipe string components by electromagnetic radiation 
processes, combine the measurement with specification information, and to 
apply machine readable labels to the pipe in response to information 
derived from measurement. 
It is yet another object of this invention to place a machine readable 
axial position index on pipe string components in conjunction with the 
labeling process, such that the distance between adjacent indices on 
made-up pipe suspended in a well bore can be machine measured. 
It is yet another object of this invention to provide a rig floor pipe 
label reader that reads labels on pipe string components and adds the 
label contents to the string run-in data registers. 
It is still a further object of this invention to provide apparatus to read 
labels from drill string components at the rig floor, compare an 
identifier such as a serial number with well site inventory data storage, 
confirm connector compatibility, and place the associated data in the 
drill string tally register. 
These and other objects, advantages, and features of this invention will be 
apparent to those skilled in the art from a consideration of this 
specification, including the attached drawings and appended claims. 
SUMMARY OF THE INVENTION 
A combination of pipe positioning, pipe handling, length measurement, 
surface labeling and associated computer equipment to measure pipe and 
place labels on the pipe containing pipe joint related data in a form 
readable by common symbol pattern recognition equipment. Optional 
equipment can determine material information for inclusion on label 
information. 
Innovation 
Having described the problems related to pipe strings before and after 
assembly into a well bore, attention is now invited to problem solutions 
made practical by apparatus, combinations, and methods of this invention. 
Available technologies are collectively applied to eliminate the need for 
manual data transcription. From the first act of pipe joint measurement to 
the use of the composite physical characteristic of the assembled pipe 
string, manual transcription and manual mathematical processing are 
minimized. Processing of collective data, to the extent practical, is 
caused to serve a cascade of purposes in the interest of accuracy and 
speed without manual transcription. 
Maximum advantage is taken of existing systems which, collectively, serve 
to make up the combination of this invention. Lasers, for instance, offer 
an excellent medium for measuring lengths, but this action alone leaves 
the principal problem of diligence in record keeping and further 
processing the collective pipe string specifications for use. 
Descriptions related to computers as used herein are related to common 
usage and not to the science of computer or software design. Inputs will 
refer to information entered into the computer from outside the computer. 
Outputs will refer to information passed from inside the computer to 
things outside the computer. Internal computer processes will be defined 
in general terms in light of ends to be achieved. 
It is recognized that short term data storage will likely be in solid state 
registers, and long term storage will likely be on some form of magnetic 
medium. Data storage and registers such as pipe string tally registers may 
be regarded as optional storage forms and are not to be regarded in a 
limiting sense. 
Information referred to as being in particular registers are convenience 
statements. As long as a classification of information can be swept by any 
identifier for a specific purpose, it may be regarded as sequestered in 
defined registers, whether or not such physical registers exist. 
The definition of a computer as used herein is a system made up of units 
which are pieces of hardware (electronic circuits, printed-circuits 
boards, switches, lights, etc.) that perform operations on given inputs to 
obtain required outputs. These operations are performed by a particular 
set of steps arranged (programmed) to occur in a particular order. 
Marking of the pipe joints may be accomplished by any suitable method; at 
least a partial list of candidate systems is below: 
(1) mechanical indentations; 
(2) surface painting; 
(3) installation of stainless steel or plastic banding materials which have 
been premarked with the coded information; 
(4) installation of flexible labels with high strength epoxy; 
(5) indentations made by electro-magnetic beam. 
Reading may be accomplished by any suitable method; at least a partial list 
of candidate systems is below; 
(1) holographic techniques (laser-barcode readers); 
(2) optical emission; 
(3) mechanical detection; 
It is reasonable to expect simple, painted-on bar codes about the pipe 
periphery to last to the well site, and that system may be used alone or 
in conjunction with other systems such as chemical etch. Painted-on bar 
codes, or equivalent, would serve the inventory need for drilling string. 
Anything painted on would likely soon be worn off. An etched-on serial 
number could then be used to relate a particular pipe joint to its 
specifications, because the specifications would have been read into data 
storage before the paint wears off. For drill string components, there are 
certain advantages in using a number format that is both manually readable 
and machine readable. Such numbers would need protection from surface 
wear, and a small milled recess in the tool joint makes this practical.

DETAILED DESCRIPTION OF THE DRAWINGS 
In FIG. 1, the mechanical system deals primarily with the measuring of pipe 
lengths and the placement of label information on the pipe. This system 
will be used in conjunction with pipe racks (not shown) which facilitate 
the rolling of pipes in serial order in front of the measuring system as 
shown. The preferred laser 1, movable on rail 1c, moves in to contact the 
pipe end. The target 1a moves in on rail 1b until it contacts the pin 
shoulder on drill string. If non-shouldered pipe is being measured, the 
target will be stopped by the pipe end. 
The activated laser measures the length and the information goes directly 
to the computer. The computer directs the marker (a laser is preferred) to 
impress the information desired onto the pipe surface. 
Data other than length to be put on the label is made available to the 
computer by any of the inputs common to the art. We prefer the keyboard 
input, but consider a magnetic strip card with manually readable data to 
be practical and safe. 
The supports are self explanatory. The wheels 2 roll the pipe if the label 
is to be put on more than one place. If a full periphery axial index line 
is to be used, the wheels are driven, while a line is generated by the 
marker beam. The wheels are powered by motor 3 on cue from the computer. 
When the wheels are used, the rails supporting the pipe are dropped when 
the pipe joint is aligned. The dropped portion is only long enough to 
allow the pipe in position to rest in the notch effect formed by two 
somewhat spaced wheels. The wheel axes are parallel to the axis of the 
pipe. 
The computer can be rather simple. A display is needed to confirm 
reasonableness of data to be marked on the label. Data storage is 
essential. We prefer a CRT display, hard copy printout ability, and disc 
data storage ability. Peripheral computerized ability to handle 
accumulated data for inventory purpose and for processing data to yield 
pipe string operational information will be described later. 
The use of alternative label forms must be considered. The label may be 
formed on a separate material and stuck on the pipe before or after the 
length code is added to the label. Additionally, printed-on labels may be 
put directly on the pipe surface or another surface to be attached to the 
pipe surface. 
FIG. 2 is the preferred embodiment of this invention for well site use. 
Pipe may not always be properly coded or even labeled when arriving at a 
well site for use. Alternative measuring systems are required. Three 
systems: (a), (b), and (c) are shown for making length inputs. 
System (a) uses a laser mounted on a portable fixture 5. There are two "v" 
shaped legs 5a on the fixture. These legs are pushed against the pipe, and 
the contact between the two v shapes and the pipe cylindrical surface 
aligns the laser parallel with the pipe centerline. The fixture is pushed 
upward until axial motion is stopped when the lower leg abuts the pipe 
connecting collar. This establishes the lower axial position index line. 
The elevators 6 are common to a drilling rig, and when running collared 
pipe, lift the pipe string by engaging the lower surface of the upper 
collar. The laser target 6a is attached to the elevator at any stable 
point. The distance between the target and the lower plane of the upper 
connecting collar is known. When activated, the laser measures the 
distance from laser to target and feeds that informatin to the computer. 
The computer adds the known distance between target and upper collar index 
as well as the known distance between the laser reference plane and the 
lower surface of the lower connecting collar. The rig floor monitor 
displays the information as a reasonableness test and, on cue, transfers 
the length data to the pipe string tally register or data storage. 
Length measurement system (b) assumes the existence of an axial position 
index line on serial pipe joints. Electromagnetic beam line reader 10 
moves up and down on rail 10a to automatically position on the lower axial 
position index line. A similar reader 11 moves up and down on rail 11a to 
align with the upper axial position index line. The relative displacement 
of the two readers from known axial separation references is automatically 
read on cue by the computer. The measured separation between these serial 
lines is the dimension after thread make-up. If the pipe string is 
suspended by the upper collar at the time of measurement, the pipe will be 
measured under the same axial tension it will experience downhole. The 
length will be the true length as installed. 
Once the line spacing is read, the dimension is displayed on the rig floor 
monitor for approval of reasonableness and, finally the dimension is 
entered into the pipe string tally register or data storage used. 
Pipe having position axial index lines will most likely have a machine 
readable label. There is no reason not to incorporate the machine label 
reader with the system (b), and such will probably be the case. The label 
reader, however, is subsequently described. 
System (c) presumes accurate length measurement is already accomplished, 
and the data is machine readable on the pipe surface. If drill string is 
involved, a reader of pencil size is passed, by hand, over the pipe joint 
serial number in a milled-out recess in the tool joint, preferably the pin 
end. The serial number goes to the computer. The serial number related 
data is accessed and, if predefined conditions are met, the data is 
briefly flashed on the monitor and directed to the drill string tally 
register. 
If production pipe string is being installed, we prefer the use of 
painted-on full periphery bar codes for each pipe joint. These bar codes 
are familiar at grocer check-out counters. The bar codes can be read from 
some distance, and we prefer a stationary rig mounted reader 15. Further 
processing of data has been defined for the pencil reader and is the same 
for this reader. 
Systems (b) and (c) can be combined for pipe string installation. 
Existing art for the laser measurement and position analyzing means of 
system (b) are typified by the teachings of U.S. Pat. No. 4,427,882, which 
by reference is made part of this specification. 
Existing art for bar code readers is typified by U.S. Pat. No. 4,431,912, 
which by reference is made part of this specification. 
The state of the art in computer science makes it unnecessary to detail the 
process steps involved in further management of data to achieve the ends 
that will presently be described. 
The pipe string tally register is complete with pipe bore size and pipe 
outside dimension. From this information, the pipe cross section area can 
be evolved and further processed to show strain per foot under specified 
axial stress. Total strain under specified hook load variation is a simple 
further program step. This information is one end product. 
Further processing is required when the pipe string is stuck. In such 
cases, there will be an observed pipe stretch under a selected hook load 
increase. The computer is programmed to subtract the stretch, for the 
hookload change observed, of each joint in turn beginning at the top, from 
the total stretch until zero is reached. This will indicate the last joint 
stressed and will indicate the point at which the string is stuck. As so 
far defined, the pipe stretch and change in hook load will have to be 
keyed in and a pre-programmed action initiated to yield stuck point data. 
Hook load sensors and hook position transducers can render the load change 
and dimension change to automate these inputs. We prefer to start the 
excursion, for several reasons, with manual input. Load and position 
sensors are well established in the art and are not detailed. For hook 
position data, the U.S. Pat. No. 4,459,752 teaches the preferred system. 
Pre-programmed functions will extract flow resistance data from the drill 
string tally and provide the collective flow resistance for the assembled 
drill string. This data can be used for a number of manual computation 
selections for flow ralated parameters. The drilling fluid specifications 
have to be manually keyed into the computer. 
The fluid flow rate at which the drill string will deliver maximum 
hydraulic horsepower downhole is often needed. For this information, the 
standpipe pressure limit is then keyed into the system. Surface gear 
losses are also keyed in. We prefer to solve for zero slope of horespower 
versus flow rate to determine optimum flow rate. That information is the 
end product for this operation. 
A print-out apparatus, connected to the computer in the usual fashion will 
print out the contents of the drill string or pipe string tally on cue. 
Pre-programming will print out only those specification factors preferred. 
The preferred computer arrangement will have a time of occurrence data 
system. This timer will provide correlation with entry of each pipe joint 
into the string tally. 
A continuous depth versus time log will require that the true length of the 
drill string, conrrected for all major modifying factors, be further 
modified by the distance between the top end of the drill string and the 
chosen earth related reference plane. The top end of the drill string is 
best defined as the top of the Kelly joint. The chosen reference plane is 
usually the earth surface. The U.S. Pat. No. 4,459,752 teaches a suitable 
method for determining the position of the drill string relative to some 
starting point such as the Kellyup position. 
The true depth versus time log may be programmed to function at depth 
intervals or at time intervals. Time interval printouts are preferred. The 
printout may be spooled over a period of time and finally printed on cue. 
It will be understood that certain features and subcombinations are of 
utility and may be employed without reference to other features and 
subcombinations. This is contemplated by and is within the scope of the 
claims. 
As many possible embodiments may be made of the apparatus of this invention 
without departing from the scope thereof, it is to be understood that all 
matter herein set forth or shown in the accompanying drawings is to be 
interpreted as illustrative and not in a limiting sense. 
The following definitions are offered as pertinent to the disclosure; 
(a) positioning means includes the supports FIG. 1 and optionally the 
wheels 2; 
(b) measuring means comprises laser system 1, and associated equipment 
commonly available; 
(c) electronic processor includes calculators or computer type equipment 
commonly available; 
(d) a label maker preferably includes the commonly available laser marking 
equipment programmable to write a label on metal in a preferred format; 
(e) laser excitation refers to the act of firing a laser beam into metal to 
produce vapors subject to analysis by conventional methods, preferably 
atomic emission spectroscopy; 
(f) machine readable refers to labels readable by conventional symbol 
pattern recognition equipment such as, but not limited to, bar code 
readers.