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Sealing Water Pressure in a Mechanical Seal

10/23/2016 5:43 AM

I tried to search in the google for finding the Cooling Water Pressure for the Mechanical Seal of the centrifugal pump.

The google link displayed many many choice, but I could not get the detail for this in question

The manufacturer of the mechanical seal wants a pressure of the cooling water 5 to 7 kg/cm^2 and I am of the opinion that a pressure of 2 Kg/cm^2 is sufficient.

Where can I have the details of this application. I request CR4 members to share their knowledge/experience.

Thanks,

DHAYANANDHAN.S

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#1

Re: Sealing Water Pressure in a Mechanical Seal

10/23/2016 6:09 AM

When an Engineer's opinion overrides a manufacturer's recommendation, the Engineer adopts the liability when something goes wrong, by default . Good luck.

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#2

Re: Sealing Water Pressure in a Mechanical Seal

10/23/2016 7:45 AM

You should ask the seal makers this question. If you fail to follow their suggestions, then you/your company take full responsibility for all ensuing damages = no warranty.

The design of the seal might require this to maintain lubrication or it will self destruct? That said, we need a greater insight into the overall picture anyway. Is this a 1/4 Hp water pump or a 5000 MW turbine we speak of?

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#5
In reply to #2

Re: Sealing Water Pressure in a Mechanical Seal

10/23/2016 10:40 PM

When I asked why such high pressure, the reply by the manufacturer is 'OUR DESIGN WHICH IS CONFIDENTIAL and CANNOT BE SHARED."

dhayanandhan.s

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#10
In reply to #5

Re: Sealing Water Pressure in a Mechanical Seal

10/24/2016 7:38 AM

Maybe you are asking the wrong questions. Do you use the telephone at times like this?

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#3

Re: Sealing Water Pressure in a Mechanical Seal

10/23/2016 11:35 AM

My 1 HP swimming pool pump is quite happy with 30 PSI. (XX Kg/cm^2)

Sadly the manufacturer/part number/any information at all about the pump (except the recommended pressure) is unknown to the forum.

So, let us know how 2 Kg/cm^2 works out for you. if you decide to use the seal outside the manufacturer's recommended specifications. At your own risk, of course.

You have been around here long enough to know that 20 questions is not the favorite game of the forum.

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#6
In reply to #3

Re: Sealing Water Pressure in a Mechanical Seal

10/23/2016 10:41 PM

The existing system is using only 2 Kg/cm^2 pressure.

DHAYANANDHAN.S

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#9
In reply to #6

Re: Sealing Water Pressure in a Mechanical Seal

10/24/2016 7:36 AM

That's not Lyn's problem.

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#12
In reply to #9

Re: Sealing Water Pressure in a Mechanical Seal

10/24/2016 12:55 PM

Dear Mr. Crabtree,

Quite True - That's not Lyn's problem.

I enjoyed your reply. Some times we have to get energised with jokes and it is so with your reply.

DHAYANANDHAN.S

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#4

Re: Sealing Water Pressure in a Mechanical Seal

10/23/2016 12:25 PM

It sounds like you need a different type seal for this application...there are several different types of mechanical seals, each with it's own requirements...

http://www.waterworld.com/articles/print/volume-27/issue-7/departments/pump-tips-techniques/back-to-basics-mechanical-seals-for-water-and-wastewater-pumps.html

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#7
In reply to #4

Re: Sealing Water Pressure in a Mechanical Seal

10/23/2016 10:43 PM

Thank you Mr. Solar Eagle for sending an information of a link which gives elaborate details.

I will study the same and I am sure I will get the answer for the issue.

DHAYANANDHAN.S

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#8

Re: Sealing Water Pressure in a Mechanical Seal

10/24/2016 2:20 AM

Is anyone paying attention to whether it is gauge pressure, absolute pressure, or differential pressure being referenced here?

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#11
In reply to #8

Re: Sealing Water Pressure in a Mechanical Seal

10/24/2016 12:49 PM

Dear Mr. Tornado,

It is gauge pressure.

DHAYANANDHAN.S

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#13
In reply to #11

Re: Sealing Water Pressure in a Mechanical Seal

10/24/2016 1:17 PM

OK. So, what are you going to do?

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#14
In reply to #11

Re: Sealing Water Pressure in a Mechanical Seal

10/24/2016 1:53 PM

What is the gauge pressure on other side of the seal?

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#15
In reply to #14

Re: Sealing Water Pressure in a Mechanical Seal

10/24/2016 2:37 PM

Why would there be a gauge on the other side at all?

That side should be atmospheric pressure.

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#17
In reply to #15

Re: Sealing Water Pressure in a Mechanical Seal

10/24/2016 3:06 PM

The other side is pressure of the fluid being pumped, at whichever place the seal interfaces to. And that is the side of interest for determining the differential pressure between seal cooling water and pumped fluid.

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#18
In reply to #17

Re: Sealing Water Pressure in a Mechanical Seal

10/24/2016 3:14 PM

OK.

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#16

Re: Sealing Water Pressure in a Mechanical Seal

10/24/2016 2:46 PM

You've got two options.

No.1 - increase the pressure to match the seal.

No.2 - change the seal for one that works at the available pressure.

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#19

Re: Sealing Water Pressure in a Mechanical Seal

10/25/2016 5:17 AM

Numerous pumping courses of action, incorporating those with pressing seals and mechanical seals, depend on seal water for viable operation. Seal water fills three principle needs: to cool the seal and the pole, to grease up the seal and to flush away pollutions in the framework.

Various elements can influence how much seal water a framework expends, including item temperature, revolution speed, seal water temperature and weight, and the encompassing framework's temperature. Without legitimate controls, notwithstanding, frameworks expend more seal water than they require.

Control valves for fixing frameworks work mechanically, similar to a family unit water tap. These valves permit administrators to flush the framework with seal water when the framework needs cooling. Be that as it may, end clients regularly keep valves completely open constantly, expanding water utilization, wastewater yield and the requirement for seal water sifting. To spare water, end clients must screen the valves and just open them when fundamental.

A stage up from mechanical control valves, stream meters can diminish seal water utilize while enhancing seal unwavering quality. These gadgets have two valves that control seal water stream and weight through a metering tube to meet the seal's prerequisites. Stream meters give weight and stream readings, which end clients can conform as important. Contrasted and unmetered frameworks, stream meters can decrease seal water use in frameworks by up to 90 percent. They likewise help seals perform at their top by keeping up appropriate seal water weight and stream.

Brilliant water control frameworks offer the best, most refined answer for seal water protection. While stream meters offer water investment funds, keen water control frameworks diminish water utilize something like 97 percent past that gave by stream meters.

These control frameworks manage water utilization in light of seal temperature, just permitting seal water to move through the framework when expected to cool the seal. The gadgets accessible available screen seal temperature and manage water course through various techniques—incorporating temperature-actuated composites with memory capacities and spring-stacked gadgets. Dissimilar to stream meters, where seal water goes through the framework once and depletes out, savvy water control frameworks reuse a similar water a few times. At the point when the seal water achieves a specific temperature, it depletes out and is supplanted with crisp water.

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#21
In reply to #19

Re: Sealing Water Pressure in a Mechanical Seal

10/25/2016 4:46 PM

All good stuff but are there any more options for our hapless blogger in there?

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#20

Re: Sealing Water Pressure in a Mechanical Seal

10/25/2016 12:24 PM

It could be the OEM wants the higher pressure to maintain sufficient velocity over the seal to keep small particles from getting lost in flow eddies?

How did you arrive at your opinion? What is the precise application, seal materials of this pump, size of pump shaft, etc?

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