Tank Stability While Converting the CRV Tank to ORV Tank for Chennai Terminal Foreshore.

Indian Oil Corporation Limited (IOCL) – Chennai Terminal Foreshore was commissioned to handle products such as MS, HSD and Bitumen, which are received through pipeline from Jetty area.

IOCL Chennai Terminal-Foreshore has entrusted iFluids Engineering to check the stability and adequacy of two numbers of Conical roof vertical water tanks with the capacity of 3700KL (19m ht. x 16m dia.). IOCL would like to understand the feasibility for these tanks to be converted as open roof vertical tanks or whether the height of the tank has to be decreased to achieve the stability.

Project Major Activities:

  1. Ultrasonic Thickness and Detailed Visual inspection for two tanks
  2. Mechanical design calculation and adequacy check for the design change

Ultrasonic Thickness and Detailed Visual inspection for two tanks:

  • Kick off meeting in Client location
  • Data collection of existing facilities and location assessment.
  • Existing inspection data and design calculation validation as per API 650
  • Site Permission (Man & Material) requisition for detailed site survey
  • Perform detailed tank visual inspection as per OISD-STD-129 & API 653
  • Assessment of damage mechanisms available for the tanks
  • Minimum 5 readings of UT Scan in each Shell plate and Roof plate
  • Perform UT thickness survey in each roof and shell nozzles
  • Preparation of tank inspection drawings and inspection summary
  • The thicknesses measured are all listed in the spreadsheet and compared with previous inspection thickness values.
  • Remaining life calculation will be performed as per API standard with respect to estimated corrosion rate.

Technician Details:

  • UT Inspection     : ASNT Level – II Technicians (UT/MT/PT/RT)

Measuring Equipment Details:

  • Calibrated Ultrasonic Thickness Gauge (Olympus 45MG)

Mechanical design calculation and adequacy check for the design change:

  • Validation of Design Basis and NDT Study Report
  • Analyze the revised process and operating conditions for conversion
  • Design Calculation as per API 650 for Open roof tank with surveyed current thickness of the tank
  • Adequacy check of the tank design for different load conditions (Wind load, Seismic Load, Full operating condition)
  • Calculation of minimum required thickness as per design calculation
  • Summarize the design parameters for the revised condition
  • If the loads and thickness values are in adequate level. The detailed report along with inspection report will be submitted to client for execution.
  • If the loads and thickness values are not adequate. The suitable remedy actions with execution details will be submitted to client.
  • Possible or suitable construction or demolition methodologies will be detailed in report.
  • Preparation and Submission of Recommendations and Results summary.
  • Technical queries and vendor queries will be addressed during execution of the tank conversion.