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Showing posts from November 9, 2019

Why we need to close the(discharge) isolation valve of a centrifugal pump during start up.

Why we need to close the(discharge) isolation valve of a centrifugal pump during startup ⁉ ️  # Answer(1)  ✳ ️ It is general practice to close the delivery valve of the centrifugal pump during start-up and it is highly recommended for the critical services where the liquid is at boiling/bubble point (Ex. Reflux pump of distillation column). The procedure is to close the valve and start the pump. After this open discharge valve slowly till 100% this stabilizes the complete system. If this procedure is not followed and the valve is kept 100% open and the pump is started, NPSHa for this will be minimum because of losses due to acceleration during startup. This will result in cavitation of the pump.  # ️ Answer(2)  1️⃣ To minimize the starting torque on the motor.  2️⃣ To load the delivery pipe network gradually if it is the only pump that feeds the network.  3️⃣ If it is a parallel-connected pump, this method will insure against any reverse ...

Steam Turbine

Steam turbine consists of 4 basic parts:-  1️⃣ Rotor, which carries the blades or buckets  2️⃣ Stator, consisting of cylinder and casing, which are often combined and within which the rotor turns 3️⃣ Nozzles or flow passages for the steam, which are generally fixed to the inside of the cylinder 4️⃣ Frame or base for supporting the stator and rotor There’re 4 Directions of the Steam inside ST:- 1️⃣ Axial Flow 🗜 It signifies steam flow substantially parallel to the axis of rotation, among blades that are set radially. This is the only arrangement used in medium and large turbines and is most commonly used also in small turbines. 2️⃣ Radial Flow ⌛ ️It’s obtained when the steam enters at or near the shaft and flows substantially radially outward among blades, which are placed parallel to the axis of rotation. 3️⃣ Tangential (Helical) Flow 🔋Tangential flow is the term applied when the steam enters through a nozzle placed approximately tangent to the ...

STEAM EJECTOR WORKING PRINCIPLE

‼️STEAM EJECTOR WORKING PRINCIPLE‼️  An Ejector is a device used to suck the gas or vapor  from the desired vessel or system. An ejector is similar to an of vacuum pump or compressor. The ejector is a static piece of equipment with no moving parts consist of 4 components:-  1️⃣ The Motive Nozzle  2️⃣ Motive Chest  3️⃣ Suction chamber  4️⃣ Diffuser  How it Works 1️⃣ The ejector converts pressure energy of motive steam or other working fluid into velocity.  2️⃣ Thermodynamic-ally , high velocity is achieved through adiabatic expansion of motive fluid through a convergent-divergent nozzle. 3️⃣ This expansion of the motive fluid from the motive pressure to the suction fluid operating pressure results in supersonic velocity at the nozzle exit. The motive fluid expands to a pressure equal to the suction fluid pressure, This creates a driving force to bring suction fluid into an ejector. 4️⃣ the velocity exiting a motiv...

Glycol Dehydration Basic Process

The process of removing water from a substance is called dehydration. Gas can be dehydrated by cooling and separating the condensed liquids, by using specially designed low-temperature separation process, by using solid desiccants, or by using a liquid desiccant. Cooling the gas and removing the free water with a separator is the simplest method of dehydration. However, this method is limited by the hydrate formation temperature unless some other hydrate preventive method has been taken. Although there are several methods for removing water from gas, the most commonly used dehydration method utilizes a liquid desiccant known as glycol An Article on Gas Dehydration Process: (Gas Conditioning and Processing) Covering ■Water in Natural Gas ■Glycol Dehydration Basic Process ▪︎Absorption ▪︎Distillation ■Process flow and Components ▪︎Inlet Separator ▪︎Contactor Column ▪︎Heat Exchanger ▪︎Flash Vessel ▪︎Filters ▪︎Reboiler ▪︎Surge Tank PLEASE READ MORE.......