Pipeline Inspection facilities at BIS Group, Coimbatore, India
API RP 574 Inspection Practices for Piping System Components,
API RP 577 Welding Inspection and Metallurgy,
API RP 571 Damage Mechanism Affecting Fixed Equipment in the Refining Industry,
API 578 Material Verification Program for New and Existing Alloy Piping Systems
ASME construction and referenced code sections also might be used such as ASME B31.3 and ASME Code Section IX.
For repair, the requirement of API STD 570, or ASME PCC-2 need to be met.
The title of ASME-PCC-2, which was first published in 2006 is: “Repair of Pressure Equipment and Piping.”
BIS GROUP have API 570 Piping Inspectors who are qualified persons to do the piping system inspection.
These are only important points or a summary of points for the process piping in-service inspection and should not be assumed as the entire piping inspection procedure.
A piping inspection procedure is a comprehensive document, which need to cover inspection methods to be employed, equipment and material to be used, qualification of inspection personnel involved and the sequence of the inspection activities at the minimum.
Creating a piping inventory list indicating the line number, pipe specification class, rating, schedule, pipe origin location (from) and pipe destination location (to)
Creating piping isometric sketches to facilitate inspection and the recording of corrosion monitoring locations (CMLs)
Dividing whole unit piping into piping circuits based on process condition and potential degradation mechanism
Selecting appropriate NDE techniques for each piping circuit based on the circuit damage mechanism
Determination of CMLs points in piping isometric sketches based on the potential for general or localized corrosion and service specific damage mechanisms
Determination of piping service class based consequence of failure and instruction stated in API 570 or based on the Risk Based Inspection method.
Carry out external inspection for corrosion, leaks, previous temporary repairs, clamps, coating breakdown, insulation damage, vibration, misalignment, pipe support deterioration specifically in touch points and to air to soil interface, pipe hanger distortion or breakage and frizz damage
External thickness measurement on CMLs on each piping circuit
Corrosion rate calculation based on metal loss in a specific time interval
Retirement thickness calculation based on the minmium required thickness and minimum required structural thickness
Remaining life calculation based on the available thickness for corrosion and the corrosion rate value
Determination of piping circuit inspection interval based remaining life calculation and piping service class
Determination of piping inspection interval for non-thinning damage mechanism
Making supplementary inspection with the proper NDE method for piping circuits susceptible to creep cracking
Making supplementary inspection with the proper NDE method for piping circuits susceptible to environmental cracking from Chloride SCC, Polythionic acid SCC, Caustic SCC, Amine SCC, Carbonate SCC, Hydrogen blistering and hydrogen induced cracking (HIC), etc.
Application of other NDE methods if it is necessary:
PEC (pulsed eddy current), LRUT (long range UT), LREM (long range electromagnetics), RT for wall thickness loss, and CUI and neutron backscatter and infra-red thermography for detection of wet insulation
MT (magnetic particle), WFMT (wet fluorescent magnetic particle), PT (penetrant testing), EC (eddy current), UT shear wave, AUT (automated UT), TOFD (time of flight diffraction), RT, ACFM (alternating current field measurement), AET (acoustic emission) for investigating cracking
Thermography for detection of fouling and hot spots
Internal inspection in opened flanges for deposition, corrosion, localized corrosion, erosion, etc.
Internal inspection of clad or lined piping for disbanding, bulging and cracking
Internal inspection of refractory lined piping for erosion, deterioration of anchors, undercutting of refractory and coke build up behind refractory
Flange joint inspection for distortion and leakage and flange face inspection, ring groove and gasket for corrosion, erosion , cracking and mechanical damage
Internal inspection of dismantled valve for corrosion, erosion, mechanical damage and cracking
Specific attention and internal inspection of critical check valves
Inspection of injection points for localized corrosion
Inspection of dead legs for corrosion
Corrosion under insulation inspection of piping in susceptible temperature (-12˚ to 175˚ C) either by advance NDT or by removal of insulation and making visual inspection
Making appropriate reporting and report keeping and implement proper system for quick access to the records