650 & 653 - P1 (50Q) Flashcards
A 10” nozzle is to be hot tapped into the first course of an in-service aboveground storage tank. What must the minimum shell thickness be in order to install this nozzle?
3/8”
A peripheral seal of an internal floating roof shall be designed to accommodate _____ inches of local deviation between the floating roof and the shell.
+/- 4
A new above ground storage tank has its bottom and second course plates constructed of ASTM A516 GR 60 steel that is thicker than 1 inch. How much of the vertical shell welds must be radiographed?
Complete radiography of each vertical seam is required.
When visually examining a weld of an aboveground storage tank, the frequency of surface porosity in the weld must not exceed one cluster (one or more pores) in any _____ inches of length and the diameter of each cluster must not exceed 3/32 inch.
4
When changing the operating temperature of an atmospheric storage tank to above 200F, all the requirements of:
API Standard 650, Appendix M shall be considered.
For tanks greater than 200’ in diameter, the design method to be used is known as:
The variable design point method.
The joint efficiency of a riveted lap joint with one rivet row is:
0.45
The minimum thickness of a tank bottom as calculated by the deterministic method of calculation shall be a minimum of _____ inches at the next inspection period (when the tank bottom / foundation design has a means to provide detection and containment of a bottom leak).
0.05”
What is the maximum acceptable weld undercutting of vertical butt joint of a reconstructed tank?
1/64”
A 65’ diameter tank by 32’ high is to be checked for settlement. How many settlement points are required around the periphery?
8 points
The space between the outer periphery of the roof and the tank shell of an external floating roof tank shall be sealed by a flexible device that provides:
A reasonable close fit to the shell surfaces.
A reconstructed tank course made from ¾” plate is welded with a low hydrogen rod. The welder undercuts a horizontal butt weld to a depth of 0.02” and he reinforces the weld with a 0.20” cap. Is it acceptable and why?
The weld is unacceptable because of the excess reinforcement and excess undercut.
The correct manual welding rod that must be used to make Hot Taps or for reconstruction of above ground storage Tanks.
E7018
The new nameplate for a reconstructed API 653 tank shall be placed:
Adjacent to existing nameplate.
Radiographs for reconstructed tanks shall be:
Retained for at least 1 year.
It is not necessary to consider the possibility of brittle fracture of a tank if the following exists. The tank shell thickness is:
Less than/equal (=) ½”, the tank operates over 60F or the membrane stress of the tank is below 7000psi.
Welds do not need a welder identification if
Roof plate welds and flange-to-nozzle neck welds.
Roof plates of an aboveground storage tank shall be repaired or replaced if the average thickness of the plates have corroded to:
Less than 0.09” in any 100 square inch area.
If the requirements of a jurisdiction are more stringent than the requirements of API 653, then the requirements of:
The jurisdiction shall govern.
Aboveground storage tanks are primarily inspected to:
Ensure the safety and integrity of the tanks.
Atmospheric storage tanks are defined as tanks that are designed to withstand an internal pressure:
Up to but not exceeding 2.5 psi gauge.
Three types of external inspections of above ground tanks are:
Routine in-service inspections, formal visual external inspection, and in-service UT thickness measurements of the shell
When corrosion rates are not known, tank bottom actual thickness shall be determined by inspection within the next ______ years of tank operation to establish corrosion rates.
10
A 48’ high by 100’ diameter aboveground storage tank is checked for out-of-plumbness. The permissible out-of-plumbness was found to be:
5”
A hot tap is installed on an aboveground storage tank. A reinforcing plate has been welded to the shell and pneumatically tested per API 650. After the valve has been installed on the hot tap nozzle, a pressure test is performed on the nozzle prior to mounting the hot tap machine. What pressure is used?
1.5 times the hydrostatic head.
A new tank is placed in service. In seven (7) years the following inspections should have been made:
Routine visual, formal visual (external), and UT inspections.
API 653 specifies what temperature for preheat on plate thickness over 1.5”?
200F
Routine visual in-service inspections of aboveground storage tanks from the ground may be done by:
Owner / user personnel other than authorized inspectors.
A formal visual external inspection by an authorized aboveground storage tank inspector shall be made at least every _____ years or at RCA/4N years, whichever is less
5
External, UT measurements of a new tank shell shall be made not later than _____ years after commissioning.
5
In no case shall the internal inspection interval of an aboveground storage tank exceed _____ years.
20
A tank built new in January, 1988 was removed from service and internally inspected January, 1998. The bottom course of the tank showed the most general corrosion (no isolated corrosion was found). The original thickness of the bottom course of the tank was 1”. The measured thickness of the bottom course at the inspection was 0.93”. Determine the corrosion rate.
0.0070”/year
When a fully hydrostatic test is required, it shall be held for ____ hours.
24
A full hydrostatic test is always required on:
A reconstructed tank.
The maximum acceptable undercutting on horizontal butt welds of a reconstructed tank is _____ inch.
1/32
The minimum number of settlement points around a tank periphery is:
8
The maximum spacing of settlement points is _____ feet around the circumference.
32
Which of the following is not considered shell distortion?
Uniform settlement of a tank.
If any provision of API 653 presents a direct or implied conflict with any statutory regulation and the statutory regulation is more stringent:
The government regulations govern.
If a contractor is to relocate or reconstruct an aboveground storage tank, the limits of responsibilities are defined by:
The owner / operator.
If a weld is made on a tank shell plate that is thicker than 1 inch, the base metal within 3 inches of the welding shall be heated to a temperature of approximately:
140F
Widely scattered pits may be ignored provided _______ and the sum of their dimensions along any vertical line does not exceed 2” in an 8” length.
No pit depth is greater than ½ tmin exclusive of the corrosion allowance.
The critical zone is that portion of the bottom or annular plate with in:
3” of the inside edge of the shell measured radially inward.
In addition to API 650 requirements, API 653 requires that _____ radiograph(s) is/are required for a repaired vertical weld joint.
1
When a weld fails RT, how many additional radiographs are required?
Two spots adjacent to the unacceptable weld section shall be RT’d.
With a horizontal sweep board 36” long, peaking shall not exceed _____ inch.
0.500”
A 48’ high tank has a diameter of 127’. What is the max out-of-plumbness allowed?
5.0”
What is the main factor in determining the efficiency of a rivet joint in a tank?
The number of rivet rows.
A new 100’ diameter tank must have at least _____ inches thick shell plates.
¼”
Welders are qualified to what standard or code?
Section IX of ASME Code
