Storage Tanks

The complete inspection according to API 653 standard makes it possible to certify the conformity of a storage tank. We can offer both external (in-service) and internal (out-of-service) inspections.

 

Deliverables :

• Complete report attesting to the conformity of the tank
• A clear plan for the tank owner on what actions to take
• Turnkey service for the requests, planning and processing of the results of various non-destructive tests

 

Torngats Advantages :

• A project management and execution methodology proven by our site experience
• A multidisciplinary team that can perform 100% of the tests independently
• Excellent knowledge of advanced tests to select the optimal techniques

The MFL technique used is able to map the thickness losses of the tank floor. This technology makes it possible to distinguish the losses of thickness facing the ground from those at the top surface.

 

Advantages :

• Mapping of the entire floor in one view
• The data processing software allows to change the repair criteria without having to collect the data again 
• Saved data allows comparison with future inspections
• Possibility of making inspections through thick coatings such as FRP

 

To consider :

• There is typically a subsequent validation of MFL measurements using phased-array ultrasonic testing.
• There are inaccessible areas near obstacles that need to be inspected ultrasonically or by a smaller MFL sweeper without data logging

 

Conformity :

• Typical technique and in accordance with API 653

Magnetic particles non-destructive testing method is very efficient and simple to perform. It detects surface defects surface in ferromagnetic materials. A magnetic yoke is generally used to create the magnetic field.

Different techniques:

• Dry powder (yellow or red)
• Black particles on white background (black & white)
• Fluorescent particles (in dark environment)
  
  

Advantages :

• Fast and effective
• Excellent probability of detection
• Applicable on various geometries
  
  

To note :

• Applicable only to ferromagnetic materials
• Detection of surface defects, or very close to the surface, only
• Requires a clean surface (no grease)
  
  

Technician certifications:

• ASNT, SNT-TC-1A, Magnetic Particles, level 2
• CGSB, Magnetic Particles, level 2

We are able to measure plate thicknesses on various elements of the tanks, such as walls, roof, floor or nozzles. We typically use phased-array ultrasonic testing which allows faster coverage and better interpretation of surface profiles.

Advantages :

• Precise thickness data
• Possibility to inspect through a uniform and well-adhered paint
• PAUT: faster coverage of large areas
• PAUT: better interpretation of surface profiles
  
  

To consider :

• Need for contact with the inspected part
• It may be difficult or impossible to take measurements from a heavily corroded contact surface

Phased-array ultrasonic thickness measurement data can be recorded by position to obtain detailed thickness mapping. Different scanners can be used, including a magnetic robot to map high or long strips of data on the wall or the roof.

Advantages :

• Efficient and detailed thickness mapping
• 60-foot range with the magnetic robot
• Thickness data available in Excel format
• In some cases, possibility of avoiding the use of elevated platforms to reach the area of interest
  
  

To consider :

• Coupling is acheived through water irrigation, requires access to water and difficult to apply in winter time
• The robot cannot go over the stiffening rings
• Requires access to electricity or a generator

The "vaccum box" is often used to validate the waterproofing of welded joints in tank floors. The technique involves applying a dedicated liquid to the weld section, placing the sealed box on top and pumping air into the box to create negative pressure. If air passes into the inspected section, the liquid will bubble and will be easily visible to the examiner.

Advantages :

• Easy to use technique
• Very effective in detecting "leaks"
  
  

To consider :

• Does not detect welding faults if air does not pass through
• A different type of box must be used for the corner joints
• Rather slow technique if there are a lot of joints to cover

In some cases, especially when there is only a manhole to access the interior, it is possible and preferable to inspect important sections of the roof by drone. Rafter clips and column tops can be effectively inspected with this method.

Advantages :

• Safer and more efficient than with a ladder
• Better inspection than from the ground
• More economical than using scaffolds
• Photos and videos can be saved for future comparison or client review
  
  

To consider :

• Less efficient when the areas of interest have deposits limiting the inspection
• Requires an experienced drone operator

The use of long-range 3D scanning is now possible thanks to the greater accessibility of LIDAR technology. With this technique, a tank can be mapped in its entirety from the outside and the inside. The points cloud obtained then makes it possible to evaluate the different types of deformation of the sheet elements (wall, roof, floor) and of the structural elements (beams).

Advantages :

• Fast and efficient data acquisition
• Allows a detailed analysis of the deformations, verticality, ovality and settlement requested by API 653.
• Visual rendering easy for the client to interpret
  
  

To consider :

• Data acquisition must be done on dry surfaces, the presence of water on the surface induces a measurement error.
• Reflective surfaces (chrome, mirror) and black surfaces require preparation.