Holiday Test – Overview; A holiday test here refers to defects in coating or lining, which are Pinhole, Void, Crack, Thin Spot or Contaminant. Holiday Test is a method for checking these defects by providing electricity through the defects in Coating/lining to Workpiece. If any area has a defect, spark or short circuit will occur. Holiday Test will be divided into two(2) main methods. According to the thickness of Coating/lining by Low Voltage or “Wet Sponge” It applies to Coat thickness less than 500 microns of High Voltage or “Spark” is used to Coating thickness greater than 500 microns. Example of understanding the methods: … Continue reading What is Holiday Test ?
Likely Location of CUI for Vessels – Bottom of Horizontal Vessel; The risk area for the Corrosion Under Insulation (CUI) for the Pressure Vessel, which is horizontal (Horizontal) is the bottom (Bottom) of the Vessel, which is where water will be trapped under the Insulation. CUI on Insulation Support Ring of Vertical Vessel and the Design for Minimize CUI; In an example of the result is corrosion An Under Insulation (CUI) Downtown Insulation Support Ring Of Vertical Vessel , especially the Support Ring in the zone below. When water is added to the Insulation of water to flow down by gravity. And imprisoned in the Insulation Support Ring makes the atmosphere remove this happen CUI violence. The design method to reduce … Continue reading Typical location of CUI corrosion on Pressure Vessel and Storage Tank
Likely Location of CUI for Piping – Penetration or Breach in the jacket (Vents); The Line Vents area of Carbon Steel Piping is one area that has a higher chance of CUI being stronger than other areas. Because this area will have the joints of the Insulation Jackets at the top (Top) of the pipes, which water will be able to penetrate easily if the Seal of the Insulation Jackets begin to deteriorate. Design of Termination of Insulation for CUI Protection (Piping); The design and method of insulation is very important in preventing water, which causes Corrosion Under Insulation (CUI) to not go … Continue reading Typical location of CUI corrosion in piping system
PRV Backpressure Testing; Speaking of PRV testing, everyone knows (1) Pop Test or Set Pressure Test. It is a test whether PRV can open at Inlet Pressure as set and or (2) Seat Tightness Test, which we call Leak Test, which is the test of leakage between Disc and Seat of PRV after Pop Test. But for Closed Bonnet PRV in a closed system and does not require Fluid is leaking to the outside (Discharge to Closed System) must be made Backpressure Test on Requirement of ASME BPVC Section VIII, Div.1 The Backpressure Test is a compressed air or gas at a pressure of at least 2 bars. Go from the outlet side of the PRV to see if the Body, Bonet, Bellow, including Gasketed Joint and Connection are leak or not. Which we will use soapy water to … Continue reading What is Backpressure testing of PRV?
PRV – Simmer; Simmer for Pressure Relief Valve (PRV) refers to the behavior of the PRV as close to launch. That is, while the pressure in the system ( Inlet Pressure) is approaching the Set Pressure but not yet Opening / Popping Pressure. See: What is PRV pop test? (Popping test) Simmer will create a small opening between Disc and Seat, which we may see Fluid inserted. Come or hear the sound of the fluid inserted through the opening and the PRV occurring Simmer may cause a discrepancy between the Disc and Seat of the PRV. If excessive simmer, it makes the surface … Continue reading What is simmer of valve (PRV/PSV)?
With referance to: Pressure Level Relationships chart PRV Testing – Blowdown; Blowdown is the % difference between Closing Pressure (Reseating Pressure) and Set Pressure. In general, Blowdown is set to 7% for ASME Section VIII and 4-6% for ASME Section I. If the blowdown is too much, PRV Will close slowly and cause a lot of Process Fluid loss. If the Blowdown is too low, PRV will cause a lot of Simmer, which causes Disc and Seat ‘s Valve can damage. Refer to: What is PRV pop test? (Popping test) PRV – Requirement of Overpressure and Blowdown per ASME Section I; For Pressure … Continue reading What is PRV blowdown?
Oxygen Scavenger (Corrosion Inhibitor); Oxygen Scavenger is a chemical used to inhibit Corrosion one that removes Oxygen in reaction Corrosion by being put into the water Boiler feed water to get rid of Oxygen , or from the rest of the Deaerator before release to manufacturing Steam. Continue reading What is Oxygen scavenger?
Pneumatic Testing Steps of Pressure Vessel per ASME Section VIII; Pressure testing using the Pneumatic Test according to ASME Section VIII has the following steps: Step 1 to increase the pressure to 50% of required pressure test ( Test, Pressure ). Gradually increase the pressure in steps, stepby 10% of Test pressure until equal to Test pressure. Test the pressure by keeping the pressure at Test pressure fora period of time. Reduce the pressure to Test pressure divided by 1.1 in order to inspect the leak of the Pressure vessel using Visual method. If no leakage is found, reduce the pressure.Complete thePneumatic test Continue reading Pneumatic Testing Steps of Pressure Vessel (ASME VIII)
Profile RT – U Tubes of Heat Exchanger; For example, Profile RT (Digital) of the U Tubes ( -Heat Exchanger, ), which can be viewed Profile thickness Tube and Profile of Corrosion happens inside Tube Profile RT – Vent Nozzle of Acid Storage Vessel; Example of Profile RT (Digital) of Vent nozzle of Sulfuric acid storage vessel which can see profile of nozzle thickness and profile of corrosion occurring within the nozzle . Profile RT – Socket Weld Gap; For Socket Weld of Piping, ASME Standard will require Gap , approximately 1.5 mm. This can be checked by the Profile RT (Digital) which made Profile RT can also be used to view a Profile of the thickness of the pipes, In. Service is also possible Profile RT for CUI Inspection ; Today share a Case Study, using Profile RT for monitoring Corrosion Under Insulation (CUI) by shooting rays through Insulation occupies Pipe Fitting … Continue reading What is Profile Radiographic Test