Frequently Asked Questions - Weld-On

Frequently Asked Questions

Solvent welding is a chemical process that uses a Primer, or the cement itself, to soften the surface of plastic Rohr and Fitting (Verbindung)s in order to weld, or fuse them together. This requires a tight, or interference fit. The solids contained in the PVC / CPVC / ABS Klebstoff will then fill the gap between the Rohr and Fitting (Verbindung). Glue such as PVC glue, on the other hand, is only a bonding cement and will not work with an interference fit.

Primers pre-soften the surface of the Rohr and Fitting (Verbindung) before the PVC / CPVC / ABS Klebstoff is applied so that maximum fusion can take place.

To remove grease, dirt, and foreign matter from the surface of the Rohr and Fitting (Verbindung) prior to application of the Primer and cement.

The Abbindezeit is the amount of time the joint is to be left undisturbed before handling. The Cure Time is the amount of time it takes the joint to be completely set and ready for pressure to be applied.

VOC stands for Volatile Organic Compounds which are emissions from materials. Low VOC products contribute to Reiniger air. The requirements for “Low VOC” have been established by SCAQMD Rule 1168/316A.

This phenomenon is caused by moisture being drawn into the cement (only at the surface) during the first part of the curing process and is not harmful to joint strength.

Low VOC PVC / CPVC / ABS Klebstoffs and Primers are currently required in California, Maryland, New Jersey and Connecticut. Requirements are also under consideration in several other states, including New York, Rhode Island, and Maine. Even where not required, Low VOC products are a good idea because they contribute to Reiniger air and a healthier environment.

Weld-On’s Low VOC PVC / CPVC / ABS Klebstoffs and Primers provide the same performance, have the same installation properties, but are better for the environment and more user-friendly than non-Low VOC products.

Yes. CPVC PVC / CPVC / ABS Klebstoff technically will work on PVC piping. However, we recommend that the correct Weld-On Primer and PVC PVC / CPVC / ABS Klebstoff for the particular application should be used. Please note that PVC PVC / CPVC / ABS Klebstoff, because of temperature limitations, is not recommended for CPVC piping.

No. The Weld-On Primer must be wet and fluid. The purpose of the Primer is to soften the joining surfaces of the Rohr and Fitting (Verbindung) allowing proper penetration and dissolution of joining surfaces prior to Weld-On PVC / CPVC / ABS Klebstoff application. This step is specifically recommended for large diameters, PVC Wandstärke 80, CPVC piping and cold weather installations.

No. For 4-inch and larger diameter piping, we recommend the use of 4-inch swab to apply our Primers and PVC / CPVC / ABS Klebstoffs. A can dauber is appropriate for use on Rohr diameters that are approximately twice the size of the dauber diameter.

No. However, we recommend the use of Primer on all PVC piping systems. Some Weld-On PVC PVC / CPVC / ABS Klebstoffs for irrigation piping can be used without Primer on non-pressure systems if local codes permit.

Identify the parameters of the particular application:

  • Rohr material – PVC, CPVC, ABS
  • Wandstärke or SDR of piping – Sch.40, Sch.80, SDR21, etc.
  • Rohr diameter
  • Working pressure of piping system
  • Ambient temperature at the time of installation
  • Temperature of media conveyance within the piping system
  • Type of media being conveyed within the piping system – water, specific chemicals, etc.
  • Other variables which may affect application and/or piping syste

Consult the Weld-On Auswahlhilfe and Produkthandbuch for more information or contact your local Weld-On sales representatives for recommendation. Please call 1-800-888-8312 for your nearest Weld-On sales representative office. If further technical assistance is required, contact our Technical Service Hotline at 1-877-477-8327.

Weld-On Primers, PVC and ABS PVC / CPVC / ABS Klebstoffs: 3 years Haltbarkeitsdauer
Weld-On CPVC PVC / CPVC / ABS Klebstoffs: 2 years Haltbarkeitsdauer

All Weld-On Primers and PVC / CPVC / ABS Klebstoffs have expiration dates imprinted on the outside of the case boxes and the manufactured date imprinted on the bottom of each can. The Haltbarkeitsdauer is also stated in the product bulletin of each Weld-On product.

Please refer to Produktliteratur and/or browse through our website for more product details.

In response to questions concerning PVC / CPVC / ABS Klebstoff joint strength vs. PVC Rohr pressures and surges; the shear strength of a well-made/fully-cured PVC / CPVC / ABS Klebstoffed joint is always stronger than the individual Rohr or Fitting (Verbindung) itself.  This is regardless of the Rohr diameter, Wandstärke of wall thickness, PVC compound formulation, or system pressure/temperature.