API 575 - (8) Methods of Inspection
2 external
(FOR AST's ONLY) If water is not available, to determine leaks, an air test may be used under careful conditions at a pressure of ____" of water pressure. Snoop detection liquid would be applied to ______ seams.
preliminary roof bottom
A _______ internal visual inspection should be the first step. The steps are to first inspect the ________, then the shell and ________.
high low
A holiday test of internal tank linings uses _____ voltage, and ______ current.
100
A minimum ____ watt halogen light bulb is typically required for tank bottom inspection.
545 25
API _____ provides info concerning grounding of tanks. The resistance total from tank to earth should not exceed ______ ohms.
dissimilar
Aluminum floating-roof leg supports need to be adequately isolated from bare carbon steel, as per API Appendix H to avoid corrosion by _______ metals.
sunlight
Blisters occur in areas receiving the most _________.
hammer UT
Bolt condition can be verified by VT, tapping with a _________, or by _ _ examination.
freezing
Broken grounding cable between the roof and shell are most common in _______ climates.
hammer UT
Cast iron components of tank interiors should not be tested using a ________, nor with the _ _ NDT method.
150
Caustic corrosion thrives in tanks operating above ______°F.
seam leaks
Coating bond failure commonly occurs below _________ ________.
blister
Coating bond failure is not easily seen unless a _________ has formed or broken.
29 1910 146
Confined space entry is detailed in ______ CFR Part _ _ _ _ . _ _ _
hammer
Crevices can collect water and can be checked by picking with a knife/scraper or tapping them with a __________.
30 30 5 30 swing
Drain lines can be hydro-tested using a two stage hydro-pneumatic test. First stage is ___ lbf/in² for _____ minutes. Second stage is at ___lbf/in² for ____ minutes at to test the ____ joints.
high
During tank roof inspection, tank roof level should be as ______ as possible if volatile liquid is in the tank.
100 lumens
Hydrogen blister inspection should be aided by sufficient candlepower, of at least ______ ______.
prod techniques
If MT is used for detecting cracks while tanks are in-service, current flow (________ _________) should not be used due to danger of sparks.
flame arrestors
If an explosion happens in a tank, ________ _________s should be immediately checked for damage.
heating coils
If caustic or amine is stored in a tank, it should be checked around connections for internal _____ units or _________.
sink
If drains are blocked on floating roofs, it may cause the roof to _______.
pyrophoric
Inspectors should be aware of accumulation of dry _________ material (self-igniting material when exposed to ambient air).
shaded
Insulation core samples may be removed, especially on the ______ side of the tank, to determine condition.
sounding
Ladders, stairways and handrails may be checked by VT and by ____________ to determine safe use.
soil thin
MFL scanning is capable of detecting _____-side corrosion, even through _____ film coatings.
multi echo thin
Modern UT _______-_______ thickness scopes allow metal thickness readings to be taken through _______ film coatings.
liquid
On float-type gauges, the float should be inspected to ensure it doesn't contain _______.
hammer
Outside stiffeners and wind girders of a tank can be inspected by VT and by ________ testing.
tubular inside
Particular attention should be given to ________ handrails which may have corroded from the _________.
29 1910
Platforms, elevated walkways and external floating roof wind girders used as walkways should be evaluated per OSHA as detailed in _ _ CFR Part _ _ _ _
12 12 rounded
Roof coupons should be ___" x ___" in size, and have ________ corners.
saturate low frequency eddy current
SLOFEC stands for:
cfr 1910
Stairways and ladder inspection is detailed in 29 _ _ _ Part _ _ _ _
caliper UT
Steel columns can be measured with ___________s and checked against original thickness to determine corrosion or loss. However, ____ is more efficient and accurate.
UT MFL
Tank bottom inspection has advanced from coupon cutting, to _ _, coupon cutting, electronic profiling, and _ _ _ scanning methods.
2015 2016
Tank entry and re-entry are detailed in API _______ and API _________.
MFL
Tank floors should be inspected over its entire area. The most common method is _ _ _ scanning.
7
Tanks built to API 650 prior to the ___th (use digit) edition may have been built with incomplete penetration of circ shell weld seams.
hydro
Tanks that have been lifted should be ______ tested or subject to engineering evaluation.
first
The ______ outside valve on all connections should be inspected.
low air
The best way to find roof leaks is with a _____-pressure ____ test.
before
Thickness measurements on tank roofs should be done ________ the tank bottom has been cleaned.
0.2 10
Typically, ____% to ____% of a tank bottom should be scanned randomly.
nozzle
Visual or eccentric measurements should be performed on flanges and _________s.
24 uncoated
When obtaining shell thickness, special attention should be given to the upper ____" of ________ shells of floating roof tanks.
both sides
Why are the uppermost areas of the shell most susceptible to corrosion? Because they are exposed to the atmosphere on ______ ______.
