Re: Pressure Vessel - Jpg Download

Dear Friends,
Pls let me know the differences between "Pressure Vessel" and "Air Receiver"
Thanks in advance.
Regards,
SSM

Dear SSM
All air receivers are pressure vessels but not all pressure vessels are air receivers.
hope you understood,
Regards,
Aquadefonte

Dear SSM,
Pressure Vessel:
A pressure vessel is a closed container designed to hold gases or liquids at a pressure substantially different from the ambient pressure.
Air Vessel:
A vessel designed for compressed-air installations that is used both to store the compressed air and to permit pressure to be equalized in the system.
Hope you are clear now.

Thanks Mr. Ragu for your clarification. Pl clarify further the air receiver need to be equipped with pressure relieve valve, pressure gauges etc., as that of pressure vessels.....
Reagards,
SSM

Dear SSM,
Please find the extracts of Maharashtra Factories Rules 1963 attached for safety measures for pressure and plant and vessels.
Hopefully all your doubts would be cleared.
Even if you have any difficulties pl let us know.
I was trying to upload extracts for your reference. Uploading failed in three attempts. If you can share you personal id shall forward it to you. (MFR 1963 Extracts.pdf:
Upload of file failed. )
Regards,
Sudhir

dear all,

please find the inputs from my side on the same. I thought of explaining in detail -

Pressure vessels

Pressure vessels are used to store and transmit liquids, vapors, and gases under pressure in general. The pressure of these finds will exert pressure equally in all direction on the walls and ends of the pressure vessels. Because of the internal loading, stresses are including on certain sections of the cylinder (pressure vessel) wall.

The pressure vessels (cylindrical or spherical tanks) are generally used in engineering to store fluid under pressure.

The main types of pressure vessels are -

• According to the end construction

• According to the dimensions

Pressure vessel according to the end construction -

According to the end construction, the pressure vessels are may be open of end or closed end. A simple cylinder with a piston is an example of open-end vessel whereas a tank is an example of closed end vessel. Due to the fluid pressure circumferential or hoop stresses are include in case of open ended vessels whereas longitudinal stresses in addition to circumferential stresses are induced in case of closed ended vessels.

Pressure vessels according to dimensions -

According to the dimensions pressure vessels may be of thin shell or thick shell. The deciding factor among thin and thick shells is its wall thickness and shell diameter if the ratio t/d is less than 1/10 the vessel is said to be thin shell and if the ratio is greater than 1/10 it is said to be a thick shell. Thin shell are used in boilers, tanks and pipes whereas thick shells are used in high pressure cylinder, tanks gun barrels.

Uses of pressure vessels -

The pressure vessels are used fluid to store such as liquid vapors and gases under pressure. Major uses of pressure vessels are as follows.

• Pressure vessels are used in steam boilers

• Pressure vessels are also used in storage of chemical in chemical plants

• Use in storage of petroleum products (petrol, diesel etc)

Air Receivers

Air receivers are tanks used for compressed air storage and are recommended to be in all compressed air systems.

Air receiver tanks are designed to provide a supply buffer to meet short-term demand spikes that can exceed the compressor capacity. They also serve to dampen reciprocating compressor pulsations, separate out particles and liquids, and make the compressed air system easier to control. In some cases, installing a larger air receiver tank to meet occasional peak demands can even allow for the use of a smaller compressor.

An air receiver in compressed air systems serves the important purposes of:

• Equalizing the pressure variation from the start/stop and modulating sequence of the compressor

• Storage of air volume equalizing the variation in consumption and demand from the system

• Collecting condensate and water in the air after the compressor

trust the above gives more idea....

Dear Mr. Sudhir,
With your experience, you can provide us more details on the same in a simple manner.
Awaiting your inputs.

Dear SSM,

Any vessel which is subjected to pressure more than atmospheric pressure is called as apressure vessel as per Factories act.

Care should be taken while manufacturing of pressure vessels.

Usually Boiler Quality Plates are used for this application.

While I was Inspecting as Inprocess check of one of our vessel at our supplier, I found that he was using 20 mm thick IS 2062 Grade B plates in place of Boiler Quality Plates. However the Chemical Test Cerificate was showing ok results. When I analysed, I came to know that IS 2062 Grade B material chemical properties are very close to BQ plates, and many suppliers use the same material. BQ plates are costlier by at least Rs 2000/ton.

This is a violation and it is important for companies to insist for Test Certificate of Material by the manufacturer.

I have manufactured a vessel of Dia 4.0 Meters Lehgth 12.0 Meters, for operating pressure of 3 kg/sqcm. The other inprocess checks followed are Ultrasonic Test of Plates, DP Test of weld Joints, 100 % radiography of weld joints, Hydro pressure test at 1.5 times of operating pressure.

The other safety systems are ass per MFR 1963.

Regards,

Sudhir

Dear Sudhir,
Thanks for your technical input and including references.
Keep on sharing. . .
Dear SSM,
I hope Mr.Sudhir given a good wrote up on your thread about your query. . .