12092016Fri
Last updateFri, 09 Dec 2016 7pm

i

HR Professionals Gather at VMA Workshop

HR Professionals Gather at VMA Workshop

Human resources managers, executives rep...

Valves in a Cement Slurry Line

Valves in a Cement Slurry Line

Basically everywhere you look in modern ...

Triple Offset Butterfly Valves

Triple Offset Butterfly Valves

Since their introduction to the market m...

The Weekly Report

New Products

  • ja-news-2
  • ja-news-3

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...

Readmore

Loading...

Industry Headlines

Siemens Industry Acquiring Mentor Graphics for $4.5 Billion

1 DAY 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 ...

Readmore

GE Oil & Gas Signs Agreement with TAG GmbH

2 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...

Readmore

‘Buy America’ Debate Holds Up Water Infrastructure Bill

21 HOURS 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...

Readmore

New Pipeline Safety Rule Expands Excess Flow Valve Requirements Again

2 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...

Readmore

Manufacturers Expecting Increased Revenues, Employment Growth In 2017

-1 DAYS 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...

Readmore

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

1 DAY 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...

Readmore

A Guide to Valve Cleaning and Specifications

Most of the time we only require that valves be free of basic dirt and debris before they are put in service. However, occasionally service requirements dictate that all traces of oil, dust and grease be removed. A prime example is valves to be used with oxygen. In that case, even a small speck of oil in a 100% oxygen environment can create a devastating explosion. One tiny metallic sliver could cause a minute spark, which is all that would be required to trigger the destruction.

 

Other media that require this level of cleanliness include numerous other pure gases, chlorine, paints and some chemicals. What all this means is that a standard, off-the-shelf valve cannot be used in these media unless it has been properly processed before installation. Decades ago, achieving this degree of cleanliness required the use of vapor degreasing machinery filled with a chlorinated solvent such as trichloroethane. These chemicals worked marvelously to clean, but they have been proved to be carcinogens, so their industrial cleaning usage has all but disappeared. In their place, environmentally friendly aqueous-based cleaners, such as Simple Green, have become the norm.


Follow the Specs

Even with the use of the right cleaning agent, however, it takes more than a simple “wash behind the ears” to ensure that a valve is clean enough for intended service. This is where cleaning standards and specifications come in. Fortunately, there are very good specifications to guide valve assemblers and technicians in the cleaning process. In fact, the American Society for Testing and Materials (ASTM) has a committee that works solely on specifications for oxygen service applications: Committee G04. This group produces ASTM G93, “Standard Practice for Material and Equipment Used in Oxygen-Enriched Environments,” which is a very thorough document and an excellent reference for valve cleaning procedures.

The Compressed Gas Association (CGA) publishes another often referenced cleaning standard: document CGA G-4.1, “Cleaning Equipment for Oxygen Service.” Many end-users that don’t have their own specific procedure reference the CGA 4.1 standard. The Manufacturers Standardization Society (MSS) also recently created a valve cleaning standard, MSS SP-138-2009, “Quality Standard for Oxygen Cleaning of Valves & Fittings.” This document is derived from many end-user specifications as well as CGA G-4.1. For chlorine service cleaning, the Chlorine Institute references cleaning procedures in its document: “Piping Systems for Dry Chlorine.”

The common denominator for all the cleaning standards is removal of all traces of oils, grease, dirt and other contaminants. The methods prescribed include scrubbing, ultrasonic cleaning, pressure blasting and sand blasting.


Rust Elimination

One important issue in cleaning is the presence of rust on carbon steel components after cleaning. With any of the prescribed cleaning processes, the protective film or rust preventative on the steel is removed, which exposes the metal to rapid oxidation, a problem that is particularly acute in humid environments. In many cases, a light blush of rust is acceptable, but gross deposits would not be. As a result, cleaning may need to be performed in a non-humid area. Additionally, carbon steel valves and components that have been cleaned require some form of corrosion protection—either desiccant bags inserted in the valve bore or an exterior wrapping with vapor phase inhibitor paper, or both.

After valves have been carefully cleaned and checked for proper cleanliness, they are usually put in protective heavy-gauge plastic bags to ensure they stay clean until installation.

Cleaning of valves is a straight-forward process that requires some diligence and quality control. However, guidance is available from various standards and specifications. Also, since the valves must be disassembled for most cleaning procedures, it’s important that the personnel involved be familiar with proper disassembly and re-assembly of the valves to be cleaned.

—————

Greg Johnson, a contributing editor to Valve Magazine, is president of United Valve (www.unitedvalve.com), which offers factory-authorized valve modifications and repair from its Houston, TX facility. Reach him at This email address is being protected from spambots. You need JavaScript enabled to view it..

  • Latest Post

  • Popular

  • Links

  • Events

Advertisement

Looking for a career in the Valve Industry?

ValveCareers Horiz

To learn more, watch the videos below or visit ValveCareers.com a special initiative of the Valve Manufacturers Association