04 ppp tte api 570 piping inspn

5/24/2018 04 PPP TTE API 570 Piping Inspn

1/35

Matthews Engineering Training Ltd

API 570

PIPING INSPECTION


2/35


API 570Piping Inspection Code

570


3/35


API 570 COVERS IN-SERVICEINSPECTION OF PIPING

To fit in with the philosophy of ANSI B31.3DESIGN CODE FOR PROCESS PIPING


4/35


THE SCOPE OF API 570

Mandatory:Almost anymetallic piping system:Raw and finished oil products

Raw and finished chemical products

Hydrogen/fuel/flare gas systemsSour/waste systems etc

Optional:Water,steam and

condensate

Piping related to mechanical

equipment

(pumps/compressors etc)

Pressure vessels

Domestic sewers etc

Everything< in dia

Non-metallic piping


5/35 Matthews Engineering Training Ltd

API 570 INSPECTION

PRACTICES

Checks are needed for specific types of corrosion and cracking:

1. Injection points

2. Dead legs

3. CUI4. Soil /Air(S/A) interfaces

5. Erosion and erosion/corrosion

6. SCC

7. Corrosion under linings

8. Fatigue cracking9. Creep cracking

10. Brittle fracture

11. Freeze damage

Well look at some of

these in more detail



INJECTION POINTS

Why is particular inspection attention (and TMLs)needed at

injection points ?

.and what are TMLs anyway



12in or 3D upstream

2ndchange of

flowdirection

downstream (o

7.6m after the

first change)

INJECTION POINT

INSPECTION AREAS

This area is

known as:The

IPC(injection

point circuit)



API 570 INSPECTION METHODS

Internal

visuals

TMLs

(4 quadrants)External

visual



DEADLEGS

Deadleg

Corrosion rates are

higher

around deadlegs

Redundant deadlegs

should be removed



CORROSION UNDER

INSULATION (CUI)



CORROSION UNDER

INSULATION (CUI)

Almost total wastage

of bolts


14/35


CORROSION UNDER INSULATION (CUI)

API identifies the areas that are most

susceptible to CUI

Mist from

cooling towers

Near steam vents

and deluge systems

Acid vapours


15/35


AllLCS pipework operating continually at 4


16/35


CORROSION UNDER FIXED LININGS

In general ,API does not

require removal of linings

for inspectionsAS LONGAS THE L INING IS IN

GOOD CONDITION

BUT


17/35


SOIL/AIR INTERFACES

All interfaces without cathodic protection


18/35


The API 570 rule is that you should inspect

areas for CUI where the insulation is damaged

CORROSION UNDER

INSULATION (CUI)


19/35


RECOMMENDED EXTENT OF CUI

EXAMINATION(BY CLASS)

Type of circuit

% NDT on areas

with damaged

insulation

% NDT on

suspect areas

within CUI

temperature

range

Class 1 75% 50%

Class 2 50% 33%

Class 3 25% 10%


20/35


EROSION AND EROSION-CORROSION

LOCATIONS


21/35


Control valves (especially when there is flash-off

Orifice plate

Pump discharges

ElbowsPipe features that produce turbulence

TMLS FOR

EROSION/CORROSIONDownstream of ..


22/35


An

example

EROSION/CORROSION


23/35


Erosion/Corrosion

after flow-restriction

features


24/35


STRESS CORROSION

CRACKING (SCC)

Rule:

In most circumstances,SCC is due to


25/35


SCC ON A GAS PIPELINE

COMPONENT


26/35


SCC ON A GAS PIPELINE

COMPONENT

Wh t i thi ?


27/35


What is this?


28/35


API 570 GUIDE ON REPAIR

PATCHES

D

Max D/2

Repair patch

Not permitted

25mm min radii

API 570 GUIDE ON REPAIR


29/35


PATCHES

Requires a full repair sleeve

Min 2D


30/35


API 570 INSPECTION

INTERVALS

The maximum permitted interval

depends on pipe class

Class 1:Highest risk/consequence

Class 2: Medium riskClass 3: Low risk

MAXIMUM API INSPECTION


31/35


MAXIMUM API INSPECTION

INTERVALS (BY CLASS)

Type of circuit Thickness

measurements

External visual

Class 1 5 years 5 years



Injection points 3 years By class

S/A interfaces - By class


32/35


API 570 PIPING

CLASSES

Class 1Flammable services/flash-off leading to brittle fractuExplosive vapours after flash-off

H2S gaseous

Hydroflouric acid

Piping over public roads


33/35


API 570 PIPING

CLASSES

Class 2Most other process piping

On-site hydrocarbons

H2, fuel gas and natural gas

On-site acid and caustics


34/35


API 570 PIPING CLASSES

Class 3Fluids that will not flash

off (even if they are

flammable)

Distillate/product

storage/loading linesOff-site acids and

caustics


35/35


API 570 SUMMARY

API 570 specifies the main points to look for

Remember the pipe classes (and their inspection

periods)

Simple wall thickness determination

570

04 ppp tte api 570 piping inspn

Documents