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HR Professionals Gather at VMA Workshop

HR Professionals Gather at VMA Workshop

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Industry Headlines

Manufacturers Expecting Increased Revenues, Employment Growth In 2017

Friday, 09 December 2016  |  Chris Guy

Economic growth in the U.S. will continue in 2017, say the nation’s purchasing and supply management executives in their December 2016 Semiannua...

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Industry Headlines

Siemens Industry Acquiring Mentor Graphics for $4.5 Billion

2 DAYS AGO

Siemens and Mentor Graphics have entered into a merger agreement under which Siemens will acquire Mentor for $37.25 per share in cash, which represents an enterprise value of $4.5 billion. Mentor will then be consolidated into Siemens Industry, according to the Atlanta Business Journal .

Mentor Graphics ...

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GE Oil & Gas Signs Agreement with TAG GmbH

3 DAYS AGO

GE Oil & Gas has signed an agreement with TAG (Trans Austria Gasleitung) GmbH, a pipeline operator with stations across Austria, to install its new Tuning Maintenance Software (TUMAS) across TAG’s fleet of 16 PGT25 gas turbines. This is the first time this solution has been rolled out across...

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‘Buy America’ Debate Holds Up Water Infrastructure Bill

1 DAY AGO

A debate in Congress is taking place over whether to restore a ‘Buy America’ provision in the Water Resources Development Act (WRDA) before a final version is voted on. The ‘Buy America’ rule already passed in the Senate version of the bill. It was then pulled from the compromi...

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New Pipeline Safety Rule Expands Excess Flow Valve Requirements Again

3 DAYS AGO

In October, 2016, The Pipeline and Hazardous Materials Safety Administration (PHMSA) announced a final rule that expands safety requirements for excess flow valves (EFVs) to multi-residential and commercial applications. That version of the rule covered the installation of EFVs in new or replaced se...

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Manufacturers Expecting Increased Revenues, Employment Growth In 2017

21 HOURS AGO

Economic growth in the U.S. will continue in 2017, say the nation’s purchasing and supply management executives in their December 2016 Semiannual Economic Forecast. Expectations are for a continuation of the economic recovery that began in mid-2009, as indicated in the monthly ISM Report on Bu...

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Poll: U.S. Economy to Grow 2.2% in 2017

2 DAYS AGO

National Association for Business Economics’ (NABE) December 2016 Outlook Survey forecasts 2.2% growth in real GDP for 2017. The annualized growth rate forecasted for 2017 inched downward to 2.2% in the current survey from 2.3% in September. Both projections illustrate the panel’s expectat...

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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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