Solvent Cement Welding: Precise Science, Excellent Results

This article is courtesy of Weld-On®, visit www.weldon.com for more information.

Solvent welding, commonly called solvent cementing, is integral to a complete and functional fluid system. Despite its key role, solvent welding is often perceived to be a very simple process, and important details of the process are often overlooked.

Ignoring the precise science of solvent welding can reduce weld strength and lead to higher maintenance costs—outcomes that damage the reputation of both the product
and the installer. Conversely, proper understanding and implementation of solvent welding translates to a product that is not only reliable and resilient, but also permanent and cost effective.

A glimpse into the solvent welding method is provided here, but be sure to consult your cement manufacturer for installation instructions.

Understand the Difference

Typically, welding requires heat to melt the component parts and pressure to force the parts to flow together. Solvent welding is a chemical weld, which means the melt is accomplished without heat. The weld is completed when the pipe is inserted into the fitting using the proper technique.

At first glance, solvent welding might seem like gluing, but the science behind the methods is different. While gluing involves placing a substance (glue) between components to bond them, solvent welding fuses the components. For fusion to happen successfully, the components must be in direct contact. In a solvent weld, 80 percent of bond strength comes from fusing the component parts.

Choose the Right Cement

Bond strength is also achieved by using the right type, combination and proportion of solvents in the cement. For example, some types of solvents are better for use in large-diameter systems and very hot weather installations, while other types are better suited to small-diameter jobs or cold weather installations.

Ensure Proper Fit

Another way to guarantee the strength of a solvent weld is to ensure proper fit. When the pipe and fitting are in direct contact, the two component parts mix with and into each other. Extra space between the pipe and fitting can compromise the strength of the weld. A poorly cut pipe or an insufficient amount of solvent cement can also reduce weld strength.

Find Out More

As with any highly technical process, solvent welding requires proper execution to produce quality results. When properly installed, a solvent-welded joint is reliable, resilient and permanent—qualities that translate to cost-savings up front and in the long run.

For more detailed information on solvent welding, visit http://www.weldon.com/technical_support to request a copy of the latest white paper: “The Science of Solvent Welding.” To ensure proper use, plumbing engineers, contractors, and designers can receive training in solvent welding techniques and may be eligible to earn continuing education credits. Visit www.lubrizolcpvc.com to find out more.

Be sure to consult your solvent cement manufacturer for detailed installation instructions when approaching any solvent welding job.