Innovative Robotic Solution to Inspect Gas Storage Laterals

Bi-directional, MFL-based crawler solution to tackle challenges in storage laterals

Operators have to contend with many obstacles in order to obtain high-resolution data for their pipelines. The inspection of gas storage laterals is no exception. Though they vary in complexity, with each lateral containing its own unique characteristics, the following obstacles were consistent in each gas lateral presented in this challenge:

  • No launchers and no receivers
  • Single access point
  • 10" lines connect to a 20" trunk line
  • Limited flow conditions available

Asset Description:

  • Location: Onshore
  • Product: Natural Gas
  • Pipeline diameter: 10"
  • Survey length: 29 & 250 m
  • Outer diamter: 273 mm
  • Wall thickness: 6.35 mm / 9.27 mm
  • Min. ID: 254 mm || Bend radius: 1.5D
  • Operating conditions: Out-of-service / Ambient
Location map for bi-directional, MFL-based crawler inspection of gas storage laterals.

Our Solution

After all alternative solutions were evaluated, it was determined that a bi-directional MFL-based crawler solution best suited the challenges present in these storage laterals.

Within five months, ROSEN designed, manufactured, assembled, and tested the new self-propelled inspection solution. The robotic solution tool consists of a crawler unit based on an innovative CAM approach. The cams are able to generate enough traction to ensure greater passage capability and sagely negotiate various obstacles, all while towing a high-resolution low-friction MFL unit.

Close up of a tool with a camera and bright light mounted in front.The camera situated on the front crawler module allows for visual monitoring of the inspection.

As with all solutions, a well-designed fail-safe system is essential; what goes in the pipeline must come out. For this application, ROSEN's engineers utilized a collapsing "gripper" failsafe and a tethering retrieval unit. This solution contained innovative elements such as:

  • High-resolution MFL technology capable of delivering 100% data coverage
  • Bi-directional/low-friction magnetizers
  • Onboard power storage
  • Visual monitoring
  • Power-consumption monitoring
  • Sensor detection of tee's
Workers inserting a tool vertically into the pipeline.The asset had only one access point, therefore the solution must be bi-directional.

Your Benefit

Performance

High-resolution complete data sets allow for a full assessment of the storage laterals' condition and play a vital role in the integrity management plan. This ensures compliance with safety standards and regulations while extending the asset's lifetime. Due to the small equipment footprint and quick setup on-site, multiple inspections can be completed within one day, allowing for optimal operational effort.

Cost-effective

The bi-directional approach avoids the need for costly pipe modifications at the interface between the trunk line and lateral as the same location is utilized for insertion and retrieval of the inspection system. As the crawler propels itself, no further field services are required for the execution of the work.