Corrosion in Heat Exchanger

There are 4 main reasons that cause corrosion in heat exchangers to need to be concerned during the inspection: Water impingement, Temperature, Vibration, Velocity. Refer to: Typical location of Corrosion on Heat Exchanger Cooling Water Corrosion in Heat Exchanger Tubes at High Water Temperature Zone; Another important factor affecting Corrosion in Heat Exchanger Tube Service at Cooling Water is the temperature. The area where the Cooling Water has a high temperature ( on the Outlet side ), there will be more fouling and corrosion than the low-temperature area. In the example, you can see from the corrosion that occurred in front of … Continue reading Corrosion in Heat Exchanger

Thermal Expansion affections in Piping system

Linear Thermal Expansion of Pipping; One factor that must be considered in the design of the piping system is Piping Flexibility. Because our pipes will stretch itself when the temperature is increased, and shrink when the temperature is dropped. Therefore, our piping system must be flexible or able to move back and forth sufficiently to support elongation or shrinkage of pipe. In ASME B31.3 Process Piping Design determines the Linear Thermal Expansion of each material. To be used to calculate how much piping will stretch or shrink according to how much temperature has changed. The values ​​in Table C-2 measure … Continue reading Thermal Expansion affections in Piping system

What is Mock-up test for In-service Welding

Following the concerns of welding defects for in-service maintenance hot works, the Mock-up test should be performed to increase the confidence level of works. See this: In-service and maintenance welding defects Mock-Up Testing ;  This comes at a Mock-up Testing for In-service welding or welding On-stream … For onstream welding, while there is fluid flowing inside the pipe or equipment The most important is the safety that is not going to burn through the weld and weld it must not happen Hydrogen cracking (HIC) according to the method used to prove that the simulated welding or the Mock-up test.  In conducting a mock-up test, the workpiece must look like or represent the actual work in the matter including:  (1) Type ( Material Spec.), and the thickness of … Continue reading What is Mock-up test for In-service Welding

In service and maintenance welding defect

In-Service Welding Concerns;  When welding, repairing or modifying pipelines or equipment that are currently being used (In-Service), the most worrying is the leak of the fluid inside. While or after doing On-line Welding. The two main reasons that cause the leak are: Burn Through: While welding at the melting area of ​​the welding, the strength will be reduced. We may not be able to withstand the Pressure at  Service value. Weld Cracking or Hydrogen Induced Cracking (HIC) from welding. The additional concern in welding is the cooling rate. Since the inside of the pipe or equipment has fluid flow, it may … Continue reading In service and maintenance welding defect

What is Valve Trim

Valve Trim;  Valve Trim is a name for Valve ‘s Internal Parts that come into contact with Process Fluid and be Worn. The deterioration caused by the use of Valve Trim can be replaced (Replaceable), including Seat, Disc, Stem, Bushing, and others. The parts of Valve that are considered Valve Trim will depend on the type of Valves in the table. Meanwhile, the Body, Yoke, and Bonnet are not considered. Valve Trims Standard: (API 600)   Continue reading What is Valve Trim

AWS D1.1 2020 Changed notes

Below is a summary of the material changes made to the 2020 edition of AWS D1.1. Format changes – moving to 11 clauses from 9. This change was made to improve clarity and it includes the addition of reference tables, formatting to mimic the normal progression of welding procedure qualification, as well as other updates to improve ease of use. Additional requirements are added when using shielding gases for use with prequalified welding procedures. Revision of the requirements for the qualification of WPSs using waveform technology (Heat input, auto-calculation, and record.) Revisions made to the qualification requirements for inspection personnel … Continue reading AWS D1.1 2020 Changed notes

Elbow corrosion in the piping system

When we find that Erosion or Erosion-Corrosion Occurs in our piping system. Elbow area is one of the points where Flow hits and causes Erosion / Erosion-Corrosion. The simple way of looking at the wear (Eroded) or the thickness of the Elbow lost (Local-Thin Area) is the Grid UTM (Ultrasonic Thickness Measurement). This method will. This allows us to obtain both the profile of the remaining Elbow thickness and the ability to find the lowest thickness in the area by looking at the Thickness Profile obtained.   In another example of the Grid UTM area Outside radius of Elbow before the … Continue reading Elbow corrosion in the piping system

API 650 / 653 – Tank Critical Zone

API 650 Storage Tank – Critical Zone in the Bottom;  API 653 Storage Tank Inspection, Repair, Alteration, and Reconstruction Code requires the tank bottom to be within 3 inches from the tank shell to be a critical zone because the area must support the weight of the tank shell that is placed near the welding line. Shell-to-Bottom makes Tank-Bottom in this area highly stressed. Critical Zone will have special requirements for inspections, repairs or reconstruction. Continue reading API 650 / 653 – Tank Critical Zone

API 650 – Storage tank Nameplate requirements

API 650 Storage Tank – Nameplates;  The Nameplate of the API 650 Aboveground Atmospheric Storage Tank as per Standard (para.10.1) specifies that the letters and numbers on the Nameplate must be at least 4 mm tall and the Nameplate must be welded or welded to the Tank Shell at the position near the Manhole or attached to the Reinforcing Plate of the Manhole. On the Nameplate, the Storage Tank must be specified as in the picture.   Continue reading API 650 – Storage tank Nameplate requirements