Abstract:
The present invention generally relates to an apparatus and a method of measuring various conditions of the pipeline. In one aspect, a method of using a tool in a pipeline is provided. The method includes placing the tool in the pipeline. The tool having a rotational control member constructed and arranged to maintain the tool in a preselected rotational orientation relative to the pipeline. The method further includes urging the tool through the pipeline while maintaining the preselected rotational orientation. In another aspect, an apparatus for use in a pipeline is provided. The apparatus includes a body and at least one rotational control member disposed around the body and extending radially to the pipeline therearound. The rotational control member is capable of maintaining the body in a preselected rotational orientation relative to the pipeline. In yet another aspect, a measurement tool for use in a pipeline is provided.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application claims benefit of U.S. Provisional Patent Application Ser. No. 60/536,957, filed Jan. 16, 2004, which application is herein incorporated by reference in its entirety. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     Embodiments of the present invention generally relate to an apparatus and a method for deriving data representative of the condition of a pipeline. More particularly, the invention relates to an apparatus and a method of preventing rotation of caliper tools and other pipeline tools in a pipeline.  
         [0004]     2. Description of the Related Art  
         [0005]     The safe and continuous operation of hydrocarbon pipeline networks is essential to the operators and users of such networks. Accordingly, such pipelines are cleaned and inspected at regular intervals to ensure their operational integrity.  
         [0006]     The conventional approach to inspection of operating pipelines is for the pipeline to be precleaned several times using a “dumb” pig. The dumb pig operates to scrape and remove debris such as wax, scale, sand, and other foreign matter from the pipeline while maintaining fluid supply via the pipeline. In a newly laid pipeline, the interior of the pipeline typically does not contain as much foreign matter and therefore the step of precleaning may not be required. In either case, a detailed inspection is subsequently performed by an inspection pig, which makes detailed measurements of the pipeline to determine the internal condition of the pipe. The inspection pig is typically equipped with inspection technologies of varying sophistication. For instance, the inspection pig may include complex tools generally comprising arrays of probes and sensors and techniques such as magnetic flux leakage (MFL) or ultrasonic scanning (at various positions along the pipeline) to detect flaws or defects, which might prejudice the pipeline&#39;s integrity.  
         [0007]     One shortcoming of conventional pigging pipeline inspection techniques is that once the defect in the pipe is detected, the data is recorded in the same manner regardless of the rotational orientation of the defect. For instance, if the defect is an interior protrusion in the pipeline, the inspection pig will record the depth of the protrusion and its location along the length of the pipeline. However, due to the constant rotational movement of the inspection pig while traveling through the pipeline, the rotational orientation of the protrusion is not indicated, that is whether the protrusion is at the top, bottom, or sides of the pipeline. Therefore, the exact circumferential location of the defect can not be easily determined from the data recorded by the inspection pig during the pigging operation.  
         [0008]     Recently, an inertial device has been developed to measure the orientation of the inspection pig within the pipeline. More specifically, a gravitationally sensitive indicator disposed in the body of the inspection pig provides an electrical signal indicating the orientation of the inspection pig. The electrical signal along with other signals provides a means of indicating the position of the inspection pig relative to the vertical. However, these devices are complex and expensive.  
         [0009]     A need therefore exists for a cost effective method and an apparatus for determining the condition of the pipeline by indicating the location and depth of a defect as well as the rotational orientation of the defect within the pipeline. There is a further need for a cost effective method and an apparatus for maintaining a tool in a preselected rotational orientation relative to the pipeline as it is urged through the pipeline.  
       SUMMARY OF THE INVENTION  
       [0010]     The present invention generally relates to an apparatus and a method of measuring various conditions of the pipeline. In one aspect, a method of using a tool in a pipeline is provided. The method includes placing the tool in the pipeline. The tool having a rotational control member constructed and arranged to maintain the tool in a preselected rotational orientation relative to the pipeline. The method further includes urging the tool through the pipeline while maintaining the preselected rotational orientation.  
         [0011]     In another aspect, an apparatus for use in a pipeline is provided. The apparatus includes a body and at least one rotational control member disposed around the body and extending radially to the pipeline therearound. The rotational control member is capable of maintaining the body in a preselected rotational orientation relative to the pipeline.  
         [0012]     In yet another aspect, a measurement tool for use in a pipeline is provided. The measurement tool includes a body and at least one flow cup disposed around the body and extending radially to the pipeline therearound. The at least one flow cup is constructed and arranged to maintain the body in a preselected rotational orientation relative to the pipeline. The measurement tool further includes at least one sensing member configurable for collecting data regarding an interior surface of the pipeline. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]     So that the manner in which the above recited features of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.  
         [0014]      FIG. 1  is a cross-sectional view of one embodiment of a pipeline tool of the present invention in a pipeline.  
         [0015]      FIG. 2  is a partial exploded view illustrating the various components of the pipeline tool. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0016]     In general, there is provided an apparatus for, and method of, preventing rotation of a pipeline tool. Generally, a caliper tool is a pipeline tool for detecting the physical condition of a pipeline by obtaining data along the entire length of the pipeline, wherein the data is representative of the physical condition. However, as defined herein, the caliper tool may pertain to any measurement tool having a body and a flow cup, wherein the measurement tool is movable through a pipeline. It will be appreciated that the term “condition” with respect to a pipeline, may embrace a variety of different and independent pipeline factors such as debris deposits, protrusions, joints, bends, etc., the combination of which will provide an overall pipeline condition profile. To better understand the novelty of the apparatus of the present invention and the methods of use thereof, reference is hereafter made to the accompanying drawings.  
         [0017]      FIG. 1  is a cross-sectional view of one embodiment of a pipeline tool  100  of the present invention in a pipeline  10 . For illustrative purposes, the pipeline tool  100  will be described hereafter as it relates to a pipeline pig. It should be understood, however, that the principles of the present invention may apply to any number of pipeline tools, such as intelligent tools.  
         [0018]     The tool  100  generally includes a body  105  disposed between a pair of forward cups  110  and a pair of rear cups  115 . The cups  110 ,  115  position the tool  100  centrally within the pipeline  10 . Additionally, the cups  110 ,  115  act as rotational control members to maintain the rotational orientation of the tool  100 . More specifically, the cups  110 ,  115  are offset at a preselected angle  175  relative to the vertical in order to maintain the tool  100  at a preselected rotational orientation as the tool  100  travels through the pipeline. In one embodiment, the preselected angle is 1 degree from the vertical. It should be understood, however, that the cups  110 ,  115  may be offset at any angle relative to the vertical without departing from principles of the present invention, such as an angle between 0.5 to 3 degrees. Furthermore, it should be understood that the cups  110 ,  115  may be arranged in a disk shape without departing from principles of the present invention, such as a disk in a typical “disk pig”.  
         [0019]     Typically, the cups  110 ,  115  have a larger outer diameter than the inner diameter of the surrounding pipeline  10  and one of the cups  110 ,  115  and preferably the forward cups  110  are impermeable to fluid flow. Therefore, after the tool  100  is inserted into the pipeline  10 , fluid flow acts against the cups  110 ,  115  and urges the tool  100  through the pipeline  10 . The rear cups  115  may also be impermeable to fluid flow or the rear cups  115  may include a hole to allow fluid flow to act against the impermeable forward cups  110  to urge the tool  100  through the pipeline  10 . The cups  110 ,  115  may be made from any type of material, such as polyurethane. As defined herein, the term fluid may comprise a liquid medium, a gaseous medium, a solid medium or combination thereof without departing from principles of the present invention.  
         [0020]     The tool  100  further includes a computer assembly (not shown). The computer assembly is typically disposed in the body  105  for receiving and processing electronic signals generated by the tool  100 . Generally, the computer assembly receives the electronic signals and stores data regarding the characteristics of the interior of the pipeline  10  as the tool  100  passes therethrough. The computer assembly may also include an electronic clock arrangement and other circuits for storage of data.  
         [0021]     The tool  100  further includes a plurality of front arms  120  disposed adjacent the forward cups  110 . Each front arm  120  is operatively attached to the body  105  and includes an odometer wheel  125  at an end thereof. The odometer wheel  125  is rotationally attached to the arm  120  to provide an electronic signal to the computer assembly to indicate the distance the tool  100  has traveled through the pipeline  10 . The electronic signal is stored in the computer assembly which is subsequently used in conjunction with other electronic signals to indicate the condition of an interior surface of the pipeline  10 . Although the tool  100  in  FIG. 1  shows front arms  120  with two wheels  125  attached thereto, any number of wheels and arms may be employed without departing from principles of the present invention. Furthermore, the arms  120  and the wheels  125  may be positioned at any location along the tool  100  without departing from principles of the present invention.  
         [0022]     The tool  100  further includes a plurality of rear arms  130  disposed adjacent the rear cups  115 . The rear arms  130  are operatively attached to the body  105 . Each arm  130  includes a roller member  135  disposed at an end thereof. The arms  130  are typically biased outward by a biasing member to allow the roller members  135  to contact the interior surface of the pipeline  10 . As the tool  100  travels through the pipeline  10 , the roller members  135  respond to changes in the configuration of the interior of the pipeline  10 , such as dents, protrusions or bulges, and subsequently send an electronic signal to the computer assembly indicating the change in configuration. The electronic signal is stored in the computer assembly which is subsequently used in conjunction with other electronic signals, such as the electronic signal from the odometer wheels  125 , to indicate the condition of the interior surface of the pipeline  10 . Although the tool  100  in  FIG. 1  shows two rear arms  130  with two roller members  135  attached thereto, any number of wheels and arms may be employed without departing from principles of the present invention. Furthermore, the arms  130  and the roller members  135  may be positioned at any location along the tool  100  without departing from principles of the present invention.  
         [0023]      FIG. 2  is a partial exploded view illustrating the various components of the pipeline tool  100 . As shown, the tool  100  includes a plurality of orientation members  150  disposed adjacent the cups  110 ,  115 . For clarity, the orientation members  150  will be discussed as they relate to the forward cups  110 . However, it should be noted that the discussion of the orientation members  150  apply equally to the rear cups  115 . The primary function of the orientation member  150  is to offset the cups  110  at the preselected angle  175 . It should be understood, however, that the cups  110 ,  115  may be offset at the preselected angle  175  in any manner known in the art without departing from principles of the present invention, such as by altering the cups  110 ,  115  themselves. Furthermore, it is within the scope of the present invention that only a selected cup, such as the front cup  110  or the rear cup  115 , is offset at the preselected angle  175 .  
         [0024]     Generally, the orientation member  150  is a ring member that is machined at a predetermined angle. In one embodiment, the predetermined angle is one degree. However, the predetermined angle (preselected angle  175 ) may be greater or less depending on the size of the tool  100 . For instance, a smaller tool may require the predetermined angle (preselected angle  175 ) of two or three degrees because of smaller diameter cups and the requirement of a minimum axial distance from the top edge of the cup to the lower edge of the cup. In this respect, the predetermined angle may be any angle without departing from principles of the present invention. Further, in one embodiment, the orientation member  150  is made from a metallic material, such as aluminum.  
         [0025]     The primary function of the orientation member  150  is to offset the cups  110  at the preselected angle  175 . In turn, the cups  110  contact the interior surface of the pipeline  10  and maintain the tool  100  at the preselected rotational orientation relative to the pipeline  10  as the tool  100  travels therethrough. For instance, for illustrative purposes only, if the front arm  120  is at the twelve o&#39;clock position when the tool  100  is in the preselected rotational orientation, the tool  100  will travel substantially along the entire length of the pipeline  10  with the front arm  120  in the twelve o&#39;clock position. It is to be understood, however, that the tool  100  may be in any preselected rotational orientation without departing from principles of the present invention. The significance of maintaining the preselected rotational orientation of the tool  100  relative to the pipeline  10  is that the data recorded by the tool  100  will indicate the exact condition of the pipeline  10 , such as the axial location, depth, and rotational orientation of the debris deposits, protrusions, joints, bends, and other characteristics.  
         [0026]     In operation, the pipeline  10  is typically cleaned by a dumb pig (not shown) and thereafter a detailed inspection of the interior of the pipeline  10  is performed by the tool  100 . Preferably, the tool  100  is introduced at one end of the pipeline  10  through a pig launcher (not shown). Within a short distance from the pig launcher, the tool  100  rotationally adjusts to a preselected rotational orientation (if not already in the preselected rotational orientation). Thereafter, the tool  100  maintains the preselected rotational orientation as it is urged through the pipeline  10  by fluid pressure acting on the cups  110 ,  115 . In one embodiment, due to the offset of the cups  110 ,  115  at the preselected angle  175 , the fluid pressure acting on an upper portion of the fluid cups  110 ,  115  causes a nose  170  of the tool  100  downward while the tool travels through the pipeline  10 . The downward position of the nose  170  along with other forces, such as gravity and fluid forces, acts to counter the rotation of the tool  100  and causes the tool  100  to maintain the preselected rotational orientation relative to the pipeline  10 . In another embodiment, the offset of the fluid cups  110 ,  115 , at the preselected angle  175  in conjunction with the lower end interference fit between the oversized diameter cups  110 ,  115 , and the inner diameter of the pipeline  10  acts to counter the rotation of the tool  100  and causes the tool  100  to maintain the preselected rotational orientation relative to the pipeline  10 .  
         [0027]     As the tool  100  travels through the pipeline, the tool detects various changes in the configuration of the pipeline  10 . For example, the arm  130  and the roller member  135  are urged radially inward in response to a protrusion formed in the interior of the pipeline  10 . The radial movement of the arm  130  and roller member  135  sends an electronic signal to the computer assembly indicating the change in configuration. The electronic signal is stored in the computer assembly which is subsequently used in conjunction with other electronic signals, such as the electronic signal from the odometer wheels  125 , to indicate the condition of the interior surface of the pipeline  10 .  
         [0028]     After the tool  100  has traveled substantially the entire length of the pipeline  10  at the preselected rotational orientation while collecting data regarding the interior condition of the pipeline  10 , the tool  100  is typically caught in a pig trap (not shown) and removed from the pipeline  10 . Subsequently, the data relating to the condition of the pipeline  10  is downloaded from the computer assembly in the tool  100 . The data contains many different aspects of the interior surface of the pipeline  10 , for instance the location, depth, and the rotational orientation of the protrusion formed in the pipeline  10 . This data is then used to determine a variety of different and independent pipeline factors such as debris deposits, protrusions, joints, and bends, the combination of which will provide an overall pipeline condition profile.  
         [0029]     While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.