API 653 Flashcards
Flange material used for tank repair and alteration shall meet the minimum requirements for the material specifications in which:
The as built standard
If at any time settlement is deemed excessive, the tank should be ______.
Emptied and Re-leveled
Perimeter welds on welded on patch plates in the critical zone to be _______.
Two-pass and examined visually and by MT or PT
Any work on a tank that changes its physical dimensions or configuration.
Alteration
The coating shall be included as an essential variable, if a protective coating ______.
Has been applied to weld edge preparations.
The maximum interpass temperature permitted, in API 653, when using the preheat alternative to PWHT welding method.
600°F
Prior to each liquid penetrant examination, the surface to be examined and all adjacent areas within ______ shall be dry and free of all dirt, grease, lint, scale, ….
1 inch
Shell Settlement Types (components)
Uniform Settlement
Rigid Body Tilting of the tank (Planar Tilt)
Out-of-Plane Settlement
Lead Letter “B”
1/2” height 1/16” thick
Backscatter
Maximum Weld Reinforcement Thickness
Table 10.1
Maximum or Minimum Radius
Table 10.2
Tank Diameter feet
Radius inches
When using the preheat alternative weld method, the temperature shall be checked ______ to assure the minimum temperature is maintained during welding.
Four inches (100mm) or four times the material thickness whichever is greater on each side of the groove.
Two factors have a significant influence on toughness and resistance to brittle fracture.
Steel Cleanliness
&
Grain Size
The reinforcing plates may be added to the ______ of the tank provided that sufficient nozzle projection exists.
Inside
The portion of the tank bottom or annular plate within 3 inches of the inside edge of the shell, measure radially inward.
Critical Zone
For tanks constructed of material having a yield strength equal to or less than ______, existing shell penetrations need not be raised if certain conditions are met.
50,000 psi.
The minimum thickness of new roof plates shall be _______, plus any corrosion allowance as specified in the repair specifications.
3/16”
When performing qualification tests for tank bottom examination procedures and personnel on a sample tank bottom, the sample should be a minimum of _____.
70ft² (21m)
Two main considerations when welding austenitic stainless steels are
Solidification cracking
&
Hot cracking
Dimensions for Nozzles
Dimensions for Nozzles/Pipe/Plate
Table 5.6
Table 5.7
Maximum permitted transmitted density between the iqi & the area of interest.
4.0 ± .05
MT examination
Shall be done by the continuous method
Either wet or dry particles
The requirements of which standard shall be considered in the evaluation and subsequent alteration to the tank roof and roof to shell junction.
Current Applicable Standard
The minimum preheat temperature is
300°F
Densitometers shall be calibrated at least every ______ & a _______ step tablet or a step wedge with densities from at least 1.0 through 4.0, shall be used.
90 days
National Standard
Austenitic stainless steel are alloys that typically contain ______.
Low carbon, chromium between 15% to 32% and, nickel between 8% to 37%
Tramp Elements
Sulfur, phosphorus, tin, antimony, and arsenic
Hardness Test
Brinell
Rockwell
Knoop
Vickers
The maximum speed of UT scanning should be ______.
Stated in the procedure