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Powell Valve Approves Flotech as Authorized Repair Facility

1 DAY AGO

The Wm. Powell Company recently approved Flotech as an authorized modification and repair facility for Powell Valves.

“Flotech has been manufacturing and repairing valves for over 40 years. Adding another high quality valve manufacturer to the list of valve companies Flotech represents speaks vol...

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CIRCOR Reports Fourth Quarter 2016 Financial Results

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CIRCOR International, Inc. reports revenue of $158 million, GAAP EPS of ($0.12) and adjusted EPS of $0.48 in the fourth quarter of 2016 . CIRCOR had an operating cash flow of $20 million and free cash flow of $17 million for the quarter. Cost control and restructuring actions continued to drive bottom...

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Southern California Updating Natural Gas Pipeline Infrastructure

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Southern California Gas Company (SoCalGas) will upgrade or replace 50 to 60 pipeline valves in 2017 to further enhance the safety of its system. The effort is part of SoCalGas' Pipeline Safety Enhancement Plan (PSEP), a multi-billion-dollar program that tests and updates the natural gas pipeline infra...

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How New U.S. Policies Will Affect the Chemical Industry

7 DAYS AGO

“In 2017, barring a recession in the U.S. and Europe or a slowdown in China, Moody’s Investor Service expects EBITDA in the chemicals industry to slip by 1 or 2% year-over-year.”

A new report from PwC predicts that the Trump administration “is likely to embrace policies that are...

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Empire State Manufacturing Expands at Fastest Rate Since 2014

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Business activity expanded at a solid clip in New York State, according to firms responding to the February 2017 Empire State Manufacturing Survey. The headline general business conditions index rose twelve points to 18.7, its highest level in more than two years. The new orders index climbed to 13.5,...

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Philly Fed Manufacturing Conditions Continued to Improve in February

6 DAYS AGO

The index for current manufacturing activity in eastern Pennsylvania, southern New Jersey and Delaware increased from a reading of 23.6 in January to 43.3 this month and has remained positive for seven consecutive months. The share of firms reporting growth continues to increase: More than 48% of the ...

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The Well-Functioning Steam Trap

vmwnt09 beyond valves 1Ultrasonic instruments are used to test a thermodynamic steam trapSteam traps are the most important link between the steam and condensate system. Malfunctioning steam traps can waste tremendous amounts of money. Here is an example: A single inverted bucket steam trap (with a one-eighth-inch orifice) blowing-thru in a 150 psi, where the steam cost is $11.00 per 1,000 lbs. of steam produced, will waste 62.49 lbs. of steam per hour and cost approximately $6,022 in fuel losses per year.

 

Steam Traps Defined

For those who are not familiar with the steam trap, it is an automatic valve that, when operating properly, opens to purge a steam system of condensate and closes with the presence of steam.

There are three types of steam traps:

  • Density operated, which includes the inverted-bucket (IB) and the float and thermostatic (FT) types
  • Thermostatic (TH), specifically, the balance-pressure thermostatic (BPT) type
  • Thermodynamic (TD), either the disc or impulse type

Trap Characteristics

vmwnt09 beyond valves 2An inverted bucket steam trapFloat and thermostatic traps consist of a ball float and a thermostatic bellows element. As condensate flows through the body, the float rises or falls, opening the valve according to the flow rate. The thermostatic element discharges air from the steam lines. They are good in heavy and light loads and on high and low pressure, but are not recommended where water-hammer is a possibility.

When these traps fail, they usually fail closed. However, the ball float may become damaged and sink down, failing in the open position. The thermostatic element may also fail and cause a fail-open condition.

Thermostatic traps have, as the main operating element, a metallic corrugated bellows that is filled with an alcohol mixture that has a boiling point lower than that of water. The bellows will contract when in contact with condensate and expand when steam is present. Should a heavy condensate load occur, such as in start-up, the bellows will remain in a contracted state, allowing condensate to flow continuously. As steam builds up, the bellows will close. Therefore, there will be moments when this trap will act as a “continuous flow” type while at other times it will act intermittently as it opens and closes to condensate and steam, or it may remain totally closed.

These traps adjust automatically to variations of steam pressure but may be damaged in the presence of water-hammer. They can fail open should the bellows become damaged or due to particulates in the valve hole that will prevent adequate closing. Sometimes the trap becomes plugged and will fail closed.

Inverted bucket traps have a “bucket” that rises or falls as steam and/or condensate enters the trap body. When steam is in the body, the bucket rises, closing a valve. As condensate enters, the bucket sinks down, opening a valve and allowing the condensate to drain.

Inverted bucket traps are ideally suited for water-hammer conditions but may be subject to freezing in low temperature climates if not insulated. When an inverted bucket trap fails, it fails open due to the bucket losing its prime and sinking, or from impurities in the system that may prevent the valve from closing.

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