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Pipe wall thickness chart-3

Pipe Wall Thickness Chart

Pipe wall thickness chart is a must-have item for me as process engineer. I usually use it when I have to size pipe, do hydraulic analysis, etc. Information I need from the chart are mostly outside diameter and inside diameter of particular pipe size.

In this post I want to share you pipe wall thickness chart based on ASME B36.19M-2004 Stainless Steel Pipe.

In this chart you can extract data of

  • Outside diameter and wall thickness in inch and mm
  • Pipe size is expressed in NPS (Nominal Pipe Schedule) and DN (Diametre Nominal)
  • Weight in pound per linear foot or kilogram per meter

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Fail-safe position

Fail-Safe Position Selection of Control Valve

In designing a processing facility, we usually use control valve to manipulates the temperature, pressure, level, or fluid flow rate in process system. The selection of control valve, which is air-to-open or air-to-close, is base on safety consideration. In case of power loss or air failure , control valve should move in safe position (fail-safe).

Fail Position

Fail position is the term used to describe how control valve will react when there is loss of power. I read there are three different fail positions. (more…)

Pipe Size Selection and Several Criteria of Pipe Size

Someone in my office asked me if there is a criteria for pipe size selection, in other words, pipe sizing criteria. One basic document that every process engineer produce in the beginning of engineering stage is process design basisIn the document, pipe size criteria shall be stated clearly.

I have involved in at least two engineering projects. Those two projects have different pipe size criteria. Which one is correct? (more…)

Reciprocating Pump P&ID Configuration

Reciprocating pump is a class of positive displacement pump which includes piston pump, plunger pump, and diaphragm pump. It is often used where a relatively small quantity of liquid to be handled and where delivery pressure is quite large. Priming is not required because it is positive displacement pump. Reciprocating pumps have lower efficiency compared to centrifugal pump.

API 674 – Positive Displacement Pump – Reciprocating covers minimum requirements for reciprocating positive displacement pumps for refinery application. The standard also covers piping and instrumentation required for the pump. (more…)

Hydraulic Pump Calculation

Yesterday I just finished doing hydraulic pump calculation for one of a project in my company. The purpose of the calculation was to determine suction pressure, discharge pressure, and pump differential head.

Pump calculation procedure is very simple.

First, you need to define pump operation condition. It includes fluid temperature, fluid specific gravity, fluid viscosity, pump normal capacity and design capacity.

Second, check your Piping and Instrumentation Diagram (P&ID) carefully. In this step you need to calculate pressure drop due to pipe line and fittings in the suction and discharge of pump. You need to list fittings and calculate pressure loss due to the fittings.

Total suction head = line loss + loss due to accessories + suction head

Do the same thing as for discharge head.

Differential head is calculated by this formula

Differential head = total discharge head – total suction head.