Looking to the Web, the Piping Design Central manual valve page provides a glimpse of the details involved with valve selection. More than a dozen links to a variety of published sources are highlighted and summarized. These include valve basics, discussions of valve standards, and specifics about butterfly, ball and plug valves.
Additional information about valves is available through some of the pull-down menus accessed by clicking "subjects" or "download" on the navigation bar near the top of the page. For the latter, under "refcharts," there are two Novotek Inc. piping "cheat sheets" that can be downloaded (right-click and save from your browser). The first includes 150 lb through 900 lb flanged gate, globe and check valve dimensions. There also is a handy pipe reference chart from OnlinePipe with pipe dimensions and weights for various schedule wall thicknesses of pipe in sizes from 1/8 in. to 144 in. OD.
One of the most comprehensive, single-source valve selection sites on the Web is probably The Valve Shop. Shortcuts on the guide page lead to descriptions of each type of valve. Powered operation and valve automation enhancements are often added to provide advantages in process quality, efficiency, safety and productivity. The navigation bar includes products, shopping information and technical resources. The latter provides industry (selected manufacturers) and technical links along with references to book sources (Amazon and Barnes & Noble) and a literature request form. A convenient product line card to help select, price and buy valves online is available. On the Tech Resources page, a Google search bar may be used for searching The Valve Shop.
The GlobalSpec valves page provides a comprehensive valve resource with links to hundreds of valve manufacturers and suppliers. Free registration is required for database access. Many of the companies have online catalogs that can be viewed directly. Others have links to company Web sites where detailed information is available. Filters on the Web page can be used to narrow choices. Details of the application, process conditions and desired materials of construction can be specified. A search bar permits selective searches of a variety of site categories. One category, the engineering Web, includes sites on the hidden Web not normally indexed by other search engines. Product announcements can be searched from the home page; the keyword "valves" yielded more than 675 items with a picture and description of each.
Forums provide an opportunity to network with others who use, specify or select valves. Some are company-sponsored, others are general. The Eng-Tips valve engineering forum is active and up-to-date with more than 6,000 registered members. The forum is searchable, includes a list of frequently asked questions and contains a number of valve engineering links. You can read the posts on the site, but must register (for free) to submit comments or questions. Some samples of the posts include: "forged valves versus cast valves," "excess flow check valve versus check valve," "cavitation due to valve closure" and "valve modifications." The latter involves the modification of the valve body of a plunger-type valve on a pressure vessel drain. Comments relate to testing procedures and liability concerns in the event of failure.
Several books about valves may be worthwhile to consider for your library. "The Valve Primer" by Brent T. Stojkov, "Valve Handbook" by Philip L. Skousen and "Valve Selection Handbook" by R.W. Zappe are available from Amazon.com. They are described and reviewed as being valuable to those involved in valve selection, specification, procurement, inspection, troubleshooting or repair, and are written so that they are understandable to both the expert and layman.
