Many valve and piping sources are available to the chemical industry. One such source is www.ces.clemson.edu/chemeng/uolab/valves1.htm.
To select the right valve for an application, you must consider factors such as safety, ease of use, durability and cost. Informative Internet resources can help resolve valve and piping selection issues.
GlobalSpec, www.globalspec.com, is a large database of technical products and services. Its Web site includes brief descriptions of each type of valve, along with the number of suppliers listed in the database. Links are available to more detailed descriptions, product specifications and valve suppliers.
The "Valve Selection Guide" (www.thevalveshop.com/menu/select.html) from The ValveShop.com also gives a basic description and comparison of valve types. Visitors to the site can price and buy valves online. Through a product link, visitors can select and view a variety of manual and automated valves and valve accessories.
Piping system design ," especially for critical or sensitive areas ," involves careful adherence to applicable process piping codes and standards. The "ASME Career Development Series Course #CDS 14" by Vincent A. Carucci presents an overview of process plant piping system design
at www.asme.org/education/prodev/ cdseries/course14.htm. The provisions contained in ASME B31.3, "Process Piping," are discussed, as are additional requirements and guidelines based on common industry practice. The overheads for the "Overview of Process Plant Piping System Design" course (www.asme.org/education/prodev/cdseries/pdf/cds14overhead.pdf) contain 133 pages of explanatory slides and detailed sketches, including a two-page briefing on process system valve selection.
The CASTI Guidebook to ASME B31.3 ," Process Piping (Third Edition) by Glynn E. Woods and Roy B. Baguley covers the 1999 code edition and the 2001 addenda (www.casti.ca/books_ebooks/B31_3.html). An in-depth study of code requirements and interpretations is provided. It is available in both hardcopy and CD-ROM. The guidebook explains specific code paragraphs and related ASME code interpretations, providing insight where even a close study of the code on its own might not produce a clear conclusion. A 61-page e-book version of the guidebook is available for free download at www.casti. ca/books_ebooks/lite/B31_3_lite.pdf.
A classroom-style professional development course might help you develop a thorough understanding of how valve and pump selection fits into piping system design and operation. The ASME/ Continuing Education Institute offers a four-day course, "Pump And Valve Selection for Optimum System Performance" (www.asme.org/pd/courseDetail.cfm?CO_ID=645). The course discusses selection of the right pump and valves for specific applications and for a system, as well as how pumps and valves interact for optimum system performance.
According to the site, the course teaches skills to help reduce equipment costs through proper selection of pumps and valves, stop potentially expensive system malfunctions by proper equipment selection, and save energy dollars that are wasted on improperly selected valves and pumps.
Although valves and pumps often are chosen for their mechanical performance, corrosive or erosive fluids might require special designs or construction materials. The United Kingdom's National Measurement Laboratory National Corrosion Service (www.npl.co.uk/npl/cmmt/ncs) advises visitors about good practice in corrosion control. A paper about pumps and valves is accessible at www.npl.co.uk/npl/cmmt/ncs/docs/pumps.pdf. Valve types are described, along with the advantages and disadvantages of each. Details are provided about corrosion types, construction materials and corrosion factors in design and use. A materials checklist also is included.
Many of us have been using computers long enough to have experienced perplexing problems. The PC Hell Web site (www.pchell.com) provides some tips, hints and troubleshooting remedies to help ease your computer troubles. The "Tech Support Hell" section (www.pchell.com/support) contains valuable resources such as spyware software and pop-up ad removal. The main page includes computer "Cliffs Notes," 10 steps to trouble-free computing and computer virus hoaxes. If long link addresses are getting you down, "Make A Shorter Link" (www.makeashorterlink.com/options.php) could be helpful. The Web site instructs users how to generate an abbreviated URL automatically.
Hodel is
Chemical Processing's Internet columnist. Contact him at aehodel@ netscape.net.