Oil and Gas - Lifetime Vessel Management

Oil and Gas - Tank/Vessel Scanning and Life Assessment

4D has developed a new technology for scanning and inspecting internal surfaces of large tanks and vessels; refinery coke drums are an example. The new method allows scanning through the top and bottom heads between cycles in less than 1 hour (the scanner is stationary) and is so accurate you can see most plate welds in the scan.

Vessel Contour Plots

Color contour plots of the "rolled out" surface of the coke drum (vertical and circumferential profiles) and the scanned data points are provided to the customer in any standard data format. Custom formatting is also available. The results can be used to track drum deformation over time, perform a finite element analysis, and estimate a drum's remaining life.

Additional Analysis

4D also offers a full range of Coke Drum analysis and instrumentation services:

  • Finite Element Analysis
  • Crack Initiation/Growth
  • Life Assessment

As well as Thermal Couple and Strain Gage Instrumentation

4D's Drumsoft Software:

4D's user-friendly Drumsoft software allows customers to plot radial variation along any vertical section or any circumferential band. Complete Drum Scan data is provided to the customer on a CD in ASCII format for easy access and archiving.

Contour Plots:

4-D's software can create contour plots of radius variation to allow for the easy visualization of shell bulges and out-of-roundness. These plots can also allow for simple comparisons to prior scans.

Vessel FEA:

BEAR can perform complete finite element analyses of coke drums using the true geometry of the drums derived from laser scan data and field measured dynamic temperature, strain and/or pressure measurements. Combining the resulting stresses with those due to the weight of coke hanging on the drum's wall allows BEAR engineers to assess the remaining life of your coke drums as a function of operating conditions.

Visual Reports and Evaluation

Img 3

photograph taken from a drum video

showing a liner weld patch (upper weld)

Img 2

circumferential weld (lower weld)

High Resolution Photographs: At right is a photograph taken from a drum video showing a liner weld patch (upper weld) and a circumferential weld (lower weld). The proprietary 4D video camera allows for very high resolution closeups.

Pipe Corrosion Evaluation

4D engineers can also scan pipeline and vessel corrosion spots and evaluate the damage using API 579, RSTRENG® or B31G to determine if surrounding metal strength is adequate to make up for the corrosion.

Scanning Data Storage

4D Imaging provides an online depository for clients scanning data and maintains an extensive collection of aggregate data for client’s use. Registered users may download their site-specific data as well as aggregate data.

The data is in ASCI format and may be processed using our proprietary software, DrumSoft or any software capable of accepting and manipulating ASCI data. A data set consists of basic drum design and operating data as shown in Table 1, the year and quarter of the scan and the raw scan data. Aggregate data sets are sanitized and do not contain refinery, vessel number or unit name information.

4D Imaging on-line Lifetime Vessel Management and Tracking (LVMT) software can reduce down time and loss production and enhance shutdown planning and inspections by allowing clients to:

  • Produce color contour maps of a complete drum or specific vertical sections of a drum (Figure 1)

    figure 1 - contour map of complete drum

  • Produce vertical slice views of drums showing deformation at different angles around the drum (Figure 2)

    figure 2 - vertical slice view

  • Produce horizontal slice views of drums showing deformation at different elevations of the drum
  • Compare the degree of deformation of on-site drums so that one can focus inspection, shutdown, repair and replacement efforts
  • Generate Difference Map that display the change in deformation of a drum over a period of time (Figure 3)

    figure 3 - difference map (growth in past 12 month period)

  • Project drum deformations based on site-specific data or aggregate data. (Figure 4)

    figure 4 - twelve-year projected distortion (based on aggregate data)

  • Use aggregate data to estimate the effect of operating parameters on a drum. (Figure 5)

    figure 5 - ten-year projected distortion (based on aggregate data and reduced cycle time)