API 570 chapter 6 Flashcards
Inspection due date may be determined through a risk assessment in accordance with API 580 and the due date may exceed ….
the typical half-life interval used in a more
conventional analysis.
When should Piping shall be inspected in accordance with code of construction requirements
at the time of installation
The minimum installation inspection should include the following items: (3)
a) verifying that piping is installed correctly, the correct metallurgy is installed, supports are adequate and secured, exterior attachments such as supports, shoes, hangers are secured, insulation is properly installed, flanged and other mechanical connections are properly assembled and the piping is clean and dry;
b) verifying the pressure-relieving devices satisfy design requirements (correct device and correct set pressure) and are properly installed.
c) Base-line thickness
what happens if the piping service changes?
establish new service conditions + PRD settings
What if the location of piping and service are changed
piping should be inspected before it is reused
An RBI assessment conducted in accordance with API 580 may be used to (2)
- determine the inspection intervals
2. next inspection due date and extent of inspection.
Class 1 piping thickness measurement/visual external time frame?
5 years / 5 years
Class 2 piping thickness measurement/visual external time frame?
10 years / 5 years
Class 3 piping thickness measurement/visual external time frame?
10 years / 10 years
Injection point piping thickness measurement/visual external time frame?
3 years / by class
Soil to Air piping thickness measurement/visual external time frame?
See API 574 for SAI / by class
Class 4 piping thickness measurement/visual external time frame?
Optional for both
Class 4 determination is determined by whom?
owner/user
interval for piping that is non - continuous?
based on the number of years of actual service instead of calendar years provided that they are
- isolated from process fluids
- not exposed to corrosive internal environments (purged)
what is class 1 piping?
services with the highest potential of resulting in an immediate emergency
Some class 1 piping type?
a) Flammable services that can auto-refrigerate and lead to brittle fracture.
b) Pressurized services that can rapidly vaporize during release, creating vapors that can collect and form an explosive mixture, such as C2, C3, and C4 streams. Fluids that can rapidly vaporize are those with
atmospheric boiling temperatures BELOW 50 °F (10 °C) or where the atmospheric boiling point is below the operating temperature (typically a concern with high-temperature services).
c) Hydrogen sulfide (greater than 3 % weight) in a gaseous stream.
d) Anhydrous hydrogen chloride.
e) Hydrofluoric acid in main and trace acid services per API RP 751.
f) Piping over or adjacent to water and piping over public throughways (refer to national or local regulations e.g.
Department of Transportation and Coast Guard for inspection of over water piping).
g) Flammable services operating above their auto-ignition temperature.
what is class 2 piping?
slowly vaporize during release such as those operating below the boiling point but above the flash point,
Some class 2 piping type? (3)
a) on-site hydrocarbons that will slowly vaporize during release such as those operating below the boiling point but above the flash point,
b) on-site hydrogen, fuel gas, and natural gas,
c) on-site strong acids and caustics
what is class 3 piping?
Services that are either flammable but do not significantly vaporize when they leak, i.e. below the flash point, or flammable but are located in remote areas and operate below the boiling point
Some class 4 piping type? (7)
a) steam and steam condensate;
b) air;
c) nitrogen;
d) water, including boiler feed water or stripped sour water;
e) lube oil, seal oil;
f) ASME B31.3, Category D services;
g) plumbing and sewers.
what is class 4 piping?
Services that are essentially nonflammable and nontoxic are in Class 4, as are most utility services.
Some class 3 piping type? (6)
a) on-site hydrocarbons that will not significantly vaporize during release such as those operating below the flash point;
b) off-site distillate and product lines to and from storage and loading;
c) tank farm piping;
d) off-site acids and caustics;
e) off-site hydrogen, fuel gas and natural gas; and
f) Other lower risk hydrocarbon piping that does not fall in Class 1, 2, or 4.
Piping that is in non-continuous service and not adequately protected from corrosive environments may experience….?
increased internal corrosion while idle.
External visual inspections, including inspections for CUI, should be conducted at intervals no greater than ………
those listed based on class 1/2/3/4
NDE inspection for CUI should suspect locations operating between ______and what type of material?
10 °F (–12 °C) and 350 °F (175 °C)
carbon steel and low alloy steel piping.
Actions/NDE performed for damage or suspect location for CUI ?
RT or insulation removal and visual inspection is normally required for this inspection
at damaged or suspect locations additional areas should be inspected and, where warranted, up to 100 % of the circuit should be inspected.
% Extent of CUI inspection for Class 1 at damaged / non damaged insulation?
75%/50%
Extent of CUI inspection for Class 2 at damaged / non damaged insulation?
50%/33%
Extent of CUI inspection for Class 3 at damaged / non damaged insulation?
25%/10%
Extent of CUI inspection for Class 4 at damaged / non damaged insulation?
optional
factors that affect CUI? (4)
a) local climatic conditions,
b) insulation design and maintenance,
c) coating quality,
d) service conditions
inspection targets (%) can increase/decrease based on….
experience