Vacuum Steam tank

WD31

My company has recently asked to repair a ruptured steam vacuum condensate tank. However, the school system believes they can use a condensate receiver tank to accept the condensate and then pump it up to the receiver tank.

I have told them they need a new vacuum pump and tank.

They will most likely ask if the existing vacuum tank can be repaired, I am sure if it can it will have to be repaired by an ASME certified welder.

Am I on the right track and who makes a reliable tank and pump system? ITT? SARCO?

thanks,
Jack

Pumpguy

Jack,

The scheme to use a condensate pump to pump over to a storage tank is a common arrangement.

The storage tank would then have to have a boiler feed pump, controlled by low water controls on the boiler. These tanks typically have a low water make up valve too, and need to be vented to atmosphere

The size of the boiler feed tank should be based on the steaming capacity of the boiler. A typical storage capacity is 10 minutes of steaming time, although I would recommend enough water storage for 20 minutes of steaming time.

Regarding the vacuum pump, and repairs to the existing tank, keep in mind that if there was a perfect vacuum in the tank, 29.92" Hg., it would be subject to atmospheric pressure on the outside, which at sea level is 14.7 PSI.

Typical system vacuum for a steam heating application is between 3" Hg. and 8" Hg. vacuum, which expressed in PSI is 1.5 to 4 PSI, so I would say ASME code welding is not really necessary.

Regarding the vacuum pump, a stand-alone vacuum pump can be applied to a new condensate pump receiver tank. If this is contemplated, I would recommend a cast iron receiver. Thin wall condensate receivers can flex, oil can style, depending on the amount of pressure difference between the inside and outside.

Also, keep in mind that with a vacuum now on the condensate receiver, the pump will need to handle a greater pressure drop to discharge from a vacuum.

We can also supply stand alone vacuum pump packages to supplement or replace the vacuum producer on many existing vacuum condensate pump packages.

In addition to our own Type CLS vacuum condensate pump packages, SHIPCO is another good manufacturer of this equipment.

EBEBRATT-Ed

returns are usually sized smaller with a vacuum system. will the system work without a vacuum??? Who is to say how it will operate. Chances are it will if you don't need 100& capacity. The system is probably somewhat oversized.

What made the tank rupture, rot?? traps blowing through overpressureizing the tank?