FAQs

Stuart W. Johnson & Co., Inc., with nearly 90 years of cumulative experience in the industry spread over the sales team, will periodically update this section of our site with information related to frequently asked questions (FAQs) from our customers. If you have further questions on a particular topic, please do not hesitate to reach out to a member of our sales team.

Industrial pipe is measured in Nominal Pipe Size (NPS), where as sanitary tube is measured by the outside diameter (OD) of the tube.

For more information on this subject, please see our blog post titled: "What is the difference between industrial pipe and sanitary tube?"

When the Tri-Clamp sanitary union was invented, the original sizes were 1-½” through 4”.  Each size had its own unique clamp and gasket.  After the initial introduction of the Tri-Clamp connection, it was decided that a 1” Tri-Clamp union should be added.  Instead of designing a new clamp and gasket, they decided to use the 1-½” clamp along with the same profile gasket as the 1-½” but having a smaller hole in the center.

For more information on this subject, please see our blog post titled: "WHAT SIZE IS YOUR TRI-CLAMP FITTING?"

3-A Sanitary Standards, Inc. (3-A SSI) is a not-for-profit organization that is dedicated to educating the food, beverage and pharmaceutical industries and ensuring public health through hygienic equipment design.  This is accomplished by developing industry standards and by executing a validation program to measure compliance.  The “3-A” initially referred to the three associations benefiting from the oversight, the regulatory sanitarians, the food and beverage processors and the equipment fabricators. 

For more information on this subject, please see our blog post titled: 3-A? What’s That?