ASI Group

Tunnel & Pipeline Inspections

Remote Inspections provide a safer and cost-effective alternative to dewatering tunnels and pipelines

If left unattended, what you can’t see can potentially cost millions of dollars.

It could be a leaky seal, loss of head pressure, damaged intake structure or rock debris in a tunnel that causes significant damage, costing millions of dollars in fines, repairs, lost revenue and a diminished reputation. Chances are that decaying infrastructure, especially when deep underwater, can go unnoticed.

If an asset must be taken out of service, ASI understands that time is of the essence and commits sufficient resources to provide 24-hour continuous operations for as long as the client requires.

The use of remote systems is an enabling technology that provides an inspection solution where there previously was none.

ASI has pioneered techniques and developed equipment specifically designed for underwater tunnel and pipeline inspections. Our advanced robotic vehicles are controlled from the surface and data from the vehicle sensors are displayed in real-time and recorded for future review. They use the latest navigation, sonar and video imaging equipment to provide critical data for condition assessment programs. Knowing the true condition of the assets supports the development of maintenance and repair schedules for operational and financial optimization.

Tunnel & Pipeline Inspections - ASI Group
Tunnel & Pipeline Inspections - ASI Group

ASI provides tunnel and pipeline inspections that can:

  • generate a georeferenced 3D model of the tunnel,
  • determine areas of leakage (ingress or egress),
  • provide extended live monitoring of conditions when construction activities may negatively impact tunnel or pipeline integrity,
  • acquire high resolution sonar or video imagery of specific areas of features of interest.

These unique capabilities place ASI as the world leader for long tunnel inspection work.

ASI’s comprehensive fleet of ROVs supports the inspection of tunnels and pipelines in the flooded state saving time, money and avoiding the risks associated with de-watering these structures.

With more data comes a greater peace of mind

Inspection of tunnels and pipelines can present challenges. Tunnels and pipelines are often hidden from sight, have limited access and can be several kilometers (miles) long. De-watering tunnels and pipelines for walk-through inspection is not always possible and when attempted, can be dangerous and costly. In some cases, the inspection of the tunnel or pipeline cannot be accomplished as some facilities were not built with the intent of ever isolating or dewatering them.  Leaving a tunnel or pipeline in a watered state during inspection eliminates the time required to safely dewater and eliminate water waste.

In order to provide accurate dimensional information of a tunnel, ASI operates a variety of sonar systems that use sound to measure distances in the underwater environment. Since the ability of the sonar to measure distances in not impacted by visibility, tunnels in excess of 20 meters nominal diameter have been surveyed by ASI using proprietary sonar systems configured to measure 360 degrees instantaneously.

Some of these systems provide over 1,500 points at each cross-sectional measurement. If necessary, they can do so at up to 50 times per second. The instantaneous profiles are displayed to the operators and are processed into a 3D point cloud model of the tunnel. All of this is done in real-time as the pilot flies the vehicle along the tunnel. 3D points with XYZ value provide immediate information to the owner on the tunnel condition. Further processing provides a model that is completely geo-referenced to the owner’s coordinate system. This makes ASI’s data easily integrated into a GIS system of the owner’s assets.

The Benefits
  • ROV technology allows inspection, detailed imagery and data collection while pipelines and tunnels remain flooded.
  • Tunnel inspection technology provides current-state and future-state predictions of infrastructure integrity.
  • Reduce down-time, save money and schedule upgrades through inspection protocol and planned investment.
  • Fast mobilization of a full team of expert marine engineers, commercial divers, ROV pilots and fleet of vessels.
  • World-wide experience across industries including hydroelectric, nuclear, archaeological, marine construction.
  • Versatility and state-of-the-art equipment to deal with the most complex technical assignments in the world.
  • Custom spot-repair solutions and equipment adaptation as needed to perform assignments.
  • Obtain high-accuracy data collection in flooded conditions.
  • Collection of interactive volume and surface analysis data used for comprehensive studies or investigations.
  • Customized solutions for leak detection and repair.

For over 30 years ASI has solved the world’s

toughest underwater challenges

We provide clients with experienced personnel, tailored solutions, accurate data and comprehensive reports needed to make critical, timely and cost-effective decisions regarding underwater infrastructure remediation, maintenance and repair. Our process includes the following data collection technologies:

  • HD video
  • HD images
  • Photogrammetry
  • Multibeam sonar
  • Imaging sonar
  • Side-scan sonar
  • Profiling sonar
  • Underwater laser
  • Virtual reality (for tunnel inspections)

Reporting deliverables include real-time and comprehensive reporting on all our inspections including:

  • Measurable and comparable data
  • Identification of areas of interest
  • Accurate representation of asset
  • Full synopsis of the facility and methods of inspection
  • XYZ data points with ability to export to CAD
  • Quality backup data
  • Reporting
  • Sonar mosaics
  • Volumetric assessments
  • Raw/edited inspection video

To learn more contact us today

Download a project reference to learn more about our tunnel inspection capabilities

FREQUENTLY ASKED QUESTIONS

 
What is the longest distance of ASI’s ROV inspections?
  • ASI has a fleet of ROV’s which include the longest tether in each ROV class. ASI has also used AUV’s for unlimited distance capabilities. Our longest tethered distance is currently 14 km.
 What is the accuracy of ASI’s data?
  • Accuracy is dependent on range and definition. Typical target accuracy varies from approximately 1 to 5 cm at a 1 m range depending on the sonar beam footprint. Ranging accuracy, or inner dimensional accuracy in a pipe for example, is typically 1 cm.
How much sediment can the ROSEbud™ remove?
  • 60 gallons/minute (approx. 5-10% solids) at a maximum distance of 500 ft. based on pump size. Up to 2 feet in thickness and can remove hard particles like rocks under ¾ of an inch.
How is data georeferenced?
  • For bathymetric surveys or any other type of vessel mounted mapping, GPS and an inertial movement unit (IMU) is used. In open water applications the ROV positioning can be referenced to an above water location with a USBL, up to a range of a few hundred meters. For tunnel inspections, an Inertial Navigation System (INS) is used. Both IMU and INS have accelerometers, gyroscopes and compasses installed to measure movement. ASI Technicians input start location and the INS measures small changes of movement (pitch, roll and yaw) to complete the change in current position relative to the start location.

Types of inspections available:

Contact us to learn more about our services

+1 905-643-3283
For immediate assistance, please contact our Head Office at the number above.