Pipe with Dual Grade

What is Dual Grade Stainless Steel Pipe: According to ASME BPVC Section II states that control the material characteristics such as mechanical properties (Mechanical Properties), chemical (Chemical, COMPOSITION), the Heat Treatment Through the provision of Grade supplies more than one Grade will be identified as Dual or Multiple Grade. For example, Dual Grade Stainless Steel Pipe, ASME SA-213 TP316 / 316L: Looking at the ASME SA-213 spec, you can see that 316L Low-Carbon Grade is defined to have the Carbon content lower than 316 Standard Grade, and at the same time requires that 316L have Min. Tensile Strength and Min. Yield Strength be lower. (Steel in general, if having less Carbon, will also have low Tensile Strength) This … Continue reading Pipe with Dual Grade

What is Vibration induce cracking

Vibration Induced Fatigue;  Vibration Induced Fatigue is a form of fracture due to fatigue, mechanical (of mechanical Fatigue) due to Dynamic load caused by vibration ( with Vibration) had done so at the risk of Vibration Induced Fatigue is a point there. High stress and severe shaking points. This type of damage is usually found at the small branch connections of Pressure Vessel and Piping, which are naturally high-stress points because they are discontinuous (see Stress Analysis) and are the receiving points. Vibrating force Thus, if the Support inadequate and the Small Branch Connection with Vibration ( for example, near … Continue reading What is Vibration induce cracking

What is Vortex Breaker

Vortex in Vessels;  Vortex, or vortex in Vessels, is the rotation of a liquid’s core while releasing or transferring liquid from Vessels. This appears to be caused by the Earth’s rotation. Vortex can be easily observed. In everyday life, such as flushing the toilet Releasing water from the sink or bathtub Vortex in Vessels will take gas or vapor into the liquid stream that is transferred out. This will make the refining process less efficient, the system has more pressure drop, causing Erosion from the two-phase flow at the nozzle or pipe connecting to the vessel and causing cavitation at … Continue reading What is Vortex Breaker

What is Static Head of vessel

What is “Static Head” in ASME Section VIII Vessels?  In designing the Pressure Vessels according to the ASME Section VIII Division 1, aside from not only considering the design pressure that will occur within the Pressure Vessel, but we also need to consider the weight of the Liquid within the  Vessel acting on it. The pressure caused by the weight of Liquid in Vessel is the “Static Head” which is based on the density of the liquid (Liquid Density called the p) and will have greater value as the height of the liquid from the bottom of the tank or Bottom of … Continue reading What is Static Head of vessel

Allowable Stress in ASME VIII, B31.3, API 650, API 653

Basis of Allowable (Design) Stress in ASME VIII Pressure Vessel and ASME I Boiler;  (The Allowable Stress from SMTS and Allowable Stress) as well as the ASME B31.3 Proces Piping, for ASME VIII Pressure Vessel and ASME I Boiler values Allowable Tensile Stress of Material , the Code permits used to calculate the thickness and composition. The variables that are used to handle the pressure of the Pressure Vessel and Boiler will be specified in the ASME BPVC Section II Part D, which is generally equal to A value that is less than 1/3.5 Tensile Strength and 2/3 Yield Strength … Continue reading Allowable Stress in ASME VIII, B31.3, API 650, API 653

Tension Test Acceptance Criteria for Welding Procedure Qualification

Tension Test Acceptance Criteria for Welding Procedure Qualification per ASME IX;  To qualify the welding procedure according to the ASME Section IX, the mechanical properties of the test coupon must be tested. Tension Test, which is the test of the strength of the weld by The principle of ASME is that Weld Metal must be stronger than or equal to the strength of Base Metal. Therefore, the result of the Tension Test will have Acceptance Criteria as follows. The workpiece is torn/break at Base Metal: Ultimate Tensile Strength (UTS) or Failure Stress of the workpiece must be greater than 95% … Continue reading Tension Test Acceptance Criteria for Welding Procedure Qualification

What is Lamellar tearing

Welding Defects – Lamellar Tearing;  Lamellar Tear is a crack that is a step in the base metal under the welding line. The cracks lie parallel to the work surface, especially with the Rolled Steel Plate. Lamellar Tear is caused by Tensile Stress in Through-Thickness direction. This comes from the shrinkage of the weld and the base metal itself has impurities or inclusions that are parallel to the work surface Thus causing a tear or crack Lamellar Tearing up. Continue reading What is Lamellar tearing

What is Caustic corrosion cracking

External Evidence of Caustic Leaking; Carbon Steel Piping used for Caustic Service (NaOH content) may be damaged by Caustic Cracking, especially in areas with welded and discrete areas that have high stress. Caustic leaks or leaks from the cracks will look like White salt, which can be seen with the naked eye. Therefore, when doing an external visual inspection for Caustic Piping, don’t forget to look for “White Salt” which is an Evidence that indicates that our Caustic pipe is leaking. External Evidence of Caustic Leaking – Caustic Cracking on Socket Welded Piping;  Example of Caustic leakage from Caustic (NaOH) Injection Piping … Continue reading What is Caustic corrosion cracking

Circumferential vs Longitudinal Stress

Circumferential vs Longitudinal Stress of a Cylindrical Shell in ASME VIII Vessels;  Let’s look at the formula for calculating the Cylindrical Shell thickness of the ASME Section VIII Pressure Vessel. We can see that the Minimum Thickness calculated from Circumferential Stress is approximate twice the thickness calculated from Longitudinal Stress. This is because the Circumferential Stress is twice as much as Longitudinal Stress. Therefore, when calculating Shell thickness, use the formula of Circumferential Stress. Refer to: What is Hoop Stress in pressure vessel? Continue reading Circumferential vs Longitudinal Stress