Vertiline. Wireline-conveyed MFL inspection service reduces pipeline maintenance and rehabilitation costs. Baker Atlas

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1 Vertiline Wireline-conveyed MFL inspection service reduces pipeline maintenance and rehabilitation costs Baker Atlas

2 The Vertiline wirelineconveyed Magnetic Flux Leakage (MFL) instrument provides quantified internal and external inspection data in previously inaccessible pipeline applications. The effects of time and corrosion on the world s aging pipeline infrastructure have served to increase the overall likelihood of pipeline failures, according to industry trends. The consequences of these pipeline failures, which include worker and public safety issues, environmental impact, cleanup costs, and unscheduled repair and maintenance costs, have become an area of critical concern among pipeline operators. Above A bi-directional 8-in. Vertiline instrument is shown attached to a pig and ready for launching in a single-ended operation. Right The high degree of articulation demonstrated in the 6-in. Vertiline allows the instrument assembly to negotiate 90 degree pipe bends as low as 5D.

3 As a result of these factors, pipeline operators increasingly rely on proactive mechanical integrity surveys within their pipeline systems to more effectively manage risk and reduce failures. Traditionally, the majority of this proactive pipeline inspection work was limited to long, large diameter transmission lines that were compatible with conventional in-line inspection techniques. Significantly, many operators now recognize that a high percentage of their failures can occur in shorter and/or smaller diameter pipelines, many of which were previously classified as low risk or unpiggable sections. As the cost and frequency of line failures in this category is being realized, it is apparent to operators that all pipeline failure, regardless of the diameter or length in which they occur, have the potential to create significant exposure in terms of liability, cleanup, and repair expense. Until recently, no practical inspection method existed for many of these shorter and smaller diameter applications, which include oil and gas production flowlines, product lines, river crossings, refinery, industrial, and municipal piping. Since the majority of these systems do not have an installed pig launching and receiving capability, many of these lines were simply not surveyed for lack of a suitable inspection method. Baker Atlas developed the Vertiline pipeline inspection service specifically to meet the needs of operators with short section, limited access, small diameter or unpiggable pipelines. The Vertiline service makes available, for the first time, the inspection technology, operational methods and experience to inspect the most challenging line configurations. The Vertiline service utilizes a magnetic flux leakage (MFL) inspection instrument to identify and accurately quantify internal and external anomalies such as corrosion pitting, mechanical defects, metal gain, welds, valves, tees and other mechanical pipeline features. The Vertiline instrument operates in a wireline-conveyed mode, with the pipeline off-line and purged, which allows the instrument speed and position to be accurately controlled via the wireline tether. The Vertiline inspection data is transmitted, real-time, to the data acquisition system housed in the wireline logging unit. Quantified inspection results are available on site, within hours of the job completion, to help you plan and execute an appropriate pipeline rehabilitation and repair program. Applications Pipelines lacking pig launching facilities Oil and gas production lines Gas storage and distribution lines Offshore production lines Pipeline river crossings Hazardous materials (H 2 S) lines Refinery and process lines Chemical and industrial plant piping Municipal water and sewer lines Airport fuel lines System Features Wireline-conveyed operation Bi-directional data acquisition No pig launchers / receivers required Inspect from a single access point Precise tool position and speed control Real-time data acquisition 100% internal and external inspection Differentiate ID and OD defects Differentiate metal gain and metal loss Determine defect radial (clock) position Accurate determination of defect severity Quantified log data delivered on-site.

4 Instrument Design The Vertiline pipeline instruments operate on the principle of magnetic flux leakage (MFL) inspection. The Vertiline s magnetic circuit, comprised of powerful rare-earth permanent magnets, serves to magnetize the segment of pipe undergoing inspection. Within the confines of this magnetic circuit, pipeline features such as corrosion pitting, mechanical damage, valves, tees and welds, create localized magnetic flux perturbations in the vicinity of the feature. To detect these flux leakage anomalies, an overlapping array of flux leakage (FL) sensors are deployed around the circumference of the pipe within spring-loaded inspection shoes. The FL sensors serve to record flux anomalies produced by defects for features originating on either the inner or outer surface of the pipe. An additional array of discriminator (DIS) sensors, which respond only to internal features, serve to differentiate the internal anomalies. The combined FL and DIS sensors provide 100% internal and external circumferential inspection coverage. The severity of the recorded pipeline defects is quantified through analysis of the digital data signatures. The typical Vertiline instrument consists of three primary sections; the magnetizer/fl module, discriminator module, and electronics module. The individual modules are connected via articulated knuckle-joint assemblies to maximize the pipeline bend capabilities of the assembly. The Vertiline s permanent magnetic circuit produces localized magnetic flux perturbations around internal and external pipe defects. Flux leakage (FL) sensors positioned within the magnetic circuit respond to the flux anomalies produced. S Flux Leakage Anomaly Magnet Internal Defect FL Sensor On-board orientation electronics served to record the relative clock position of all significant defects. The entire Vertiline instrument is a bi-directional assembly. This bi-directional capability is quite different from the typical in-line inspection tool configuration, which only allows the instrument to travel in one direction. Since the Vertiline instrument has no preferred direction of travel, it can be conveyed in and out of a pipeline segment through a single access point. External Defect N The bi-directional Vertiline instrument is capable of travel and data acquisition in either direction. Typical FL and DIS sensor response to external, internal and through-wall defects is shown in the idealized data signatures. FL sensors respond to both internal and external features, while DIS sensors respond only to features with an internal component such as internal and through-wall defects. FL DIS OD Defect FL FL/Magnetizer Module Knuckle ID Defect DIS Discriminator Module Through-wall Defect Knuckle Electronics Module Data Transmission Wireline

5 Operations/Data Acquisition The Vertiline instrument series is a wirelineconveyed, rather than in-line, inspection system. Wireline-conveyed operation simply means that the force required to convey the instrument through the pipeline is provided by the wireline, rather than the product, as is the case with in-line inspection tools. Data gathered by the Vertiline instrument are transmitted via electrical conductors within the wireline to the acquisition computer housed in the data-logging unit. The data acquisition process may be viewed real-time from the acquisition unit s color monitor. The wireline-conveyance system offers several unique operational advantages over in-line systems. These advantages include positive instrument speed control, precise distance measurement (provided by the wireline measuring system) and bi-directional operation. This example from a U.S. Military Base illustrates severe external corrosion in a 6-in. jetfuel line. The photo on the left corresponds to a 57% penetration external defect, while the photo on the right indicates an area of severe external corrosion with a 100% pinhole penetration. Both defects were excavated and removed from the line. Typical Vertiline operation takes place through one or more access point in an evacuated line. In a single-ended operation, the Vertiline instrument and the wireline tether are first attached to a bi-directional pig. The Vertiline/pig combination is then launched from a short spool section flanged to the pipeline, and pumped through the line with compressed air, nitrogen or water. A wireline pack-off assembly maintains the pressurized seal on the wireline as the Vertiline instrument is conveyed through the pipeline. Air Compressor or Nitrogen Pumping Unit Data Acqusition Unit Vertiline Instrument Bi-directional Data Acquisition In single-ended operations, the bi-directional Vertiline instrument and wireline are attached to a bi-directional pig and conveyed inside the line with compressed air or nitrogen. Data acquisition can occur in both directions, producing a main and repeat survey on a single round-trip.

6 Operations/Data Acquisition When the furthest point of interest is reached, the line pressure is released, and the wireline drawworks on the logging unit is used to pull the Vertiline instrument back to the point of origin. Data acquisition can occur on both runs of the survey, producing a main and repeat pass with a single roundtrip. The logging unit s optical encoder, used to measure wireline movement, maintains precise speed and distance control. The capability to review inspection data realtime, as well as to have immediate digital data review in the unit, ensures that the proper inspection data and repeat sections have been acquired during the operation. Double-ended operations are similar in most respects to single-ended operations, but availability of a second access location allows the Vertiline instrument to be conveyed by two wireline units, one attached to either end of the tool. Double-ended operations begin by conveying the wireline only (no instrument) from the data acquisition unit through the pipeline via the pig/compressed gas method described previously. Once the data acquisition wireline is received at the second access location, the Vertiline instrument and the mechanical wireline are attached. With the Vertiline instrument positioned between the two units, data acquisition can now proceed in the direction of the data unit, and the direction can be reversed when required. Repeat sections, multiple runs or line obstructions can now be easily handled with the flexibility afforded by the bi-directional tool and double-ended operations. The photo and log data combination indicates an area of external mechanical damage that was excavated and removed from a 6-in. airport jet-fuel line. This series of field photos illustrates a variety of operational and launch configurations used to access lines in difficult terrain or confined areas. Mechanical Logging Unit Bell-hole Access Air Compressor or Nitrogen Pumping Unit Existing Riser Data Acqusition Unit Vertiline Instrument Double-ended acquisition allows a high degree of operational flexibility, such as the ability to negotiate mid-line restrictions and make multiple passes over areas of interest.

7 Specifications Instrument 2 inch 3 inch 4 inch 6 inch 8 inch 10 inch 12 inch 14 inch 16 inch 18 inch 20 inch 22 inch 24 inch (Series No.) (4902) (4903) (4904) (4936) (4938) (4940) (4942) (4942) (2907P) (2907P) (2907P) (2907P) (2907P) FL Sensors (Flux Leakage) DIS Sensors (ID Discrininator) na na na Body Wall (in): min: max: *Bend Radius (D): 15D 10D 10D 5D 5D 5D 5D 5D 29D 28D 16D 14D 24D **Hard Tool Diameter (in): Heavy Wall Tool (in): Tool Length (in): Tool Weight (lbs): Defect Orientation: na yes yes yes yes yes yes yes na na na na na Logging Speed (ft/min): The 2 inch through 14 inch specifications apply to single conductor/permanent magnet instrument designs. The 16 inch through 24 inch specifications apply to multi-conductor/electromagnetic instrument designs. * Bend radius indicated for the maximum negotiable pipe body wall. Bend radius improves slightly in thinner wall pipe. ** Indicates minimum collapsed tool diameter in maximum negotiable body wall.

8 Global Headquarters P.O. Box 1407 ( ) 2001 Rankin Road Houston, Texas Tel Asia-Pacific 273 Jalen Ahmad Ibrahim Singapore Tel Fax Middle East P.O. Box 6875 Dubai United Arab Emirates Tel Fax Northern Europe Stoneywood Park, Dyce Aberdeen, Scotland AB21 7EA, U.K. Phone: Fax: Southern Europe & Mediterranean Via Sangro 1 Spoltor, Pescara Italy Phone: Fax: Sub-Saharan Africa 455 London Road Isleworth, Middlesex TW7 5AA, U.K. Tel Fax Canada th Street Avenue S.W. Calgary, Alberta T2P 3C5 Canada Tel Fax Latin America P.O. Box 1407 ( ) 2001 Rankin Road Houston, Texas Tel North America Sales 1010 Rankin Road Houston, Texas Tel Fax U.S. Land 2710 Forum Drive Grand Prairie, Texas Tel Fax U.S. Offshore P.O. Box 1407 ( ) 2001 Rankin Road Houston, Texas Tel Export Sales P.O. Box 1407 ( ) 2001 Rankin Road Houston, Texas Tel Copyright 1998 Western Atlas International, Inc. All rights reserved. A Rev. 3/ M TGI