CoatingsPro Magazine Supplements

ROOF 2018

CoatingsPro offers an in-depth look at coatings based on case studies, successful business operation, new products, industry news, and the safe and profitable use of coatings and equipment.

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Page 38 of 39

COATINGSPRO ROOF COATINGS 2018 39 SPONSORED CONTENT PX-7 Spray Gun for SPF Roofi ng PMC Takes a Good Design to an Even Greater Level e SPF Roofi ng Industry was started by pioneers who were convinced of the benefi ts that polyurethane spray foam could bring to fl at roofs in all markets. Today, conceivably every shape of roof has been sprayed including the iconic Superdome in New Orleans—the largest fi xed dome struc- ture in the world¹. Polyurea coatings are now applied over SPF for LEED Certifi cation, and companies like SprayWorks and HERTEC Solutions have designed spraybots for controlled application. anks to the pioneers, SPF Roofi ng is a thriving and viable industry. In the initial days, mechanical purge valving rod spray guns were almost exclusively used for SPF roofi ng applica- tions. e reliability and quality of the mix allowed craftsmen to install with confi dence. e large volume and low veloc- ity, wide spray pattern were benefi cial for productivity but required mechanical skill to optimize the trigger time. As air purge direct-impingement spray technology that originated in OEM applications found its way to the indus- trial markets in the late 1990s, it gained favor by many for the ease of learning how to operate the gun, and the lack of valving rod adjustment. ey could spray large volumes of material and air purge guns became a viable option. Being an air purge spray gun, if there was moisture in the air lines it would blow onto the substrate when the trigger was released, creating potential blisters from the Iso reacting with the water more quickly than the Poly component. It has been argued that the spray pattern had a higher velocity, though this is also a function of pressure settings. Polyurethane chemistry has changed and expanded over the years. e equipment, while updated and optimized, is still based on the same original design principles required to mix and spray fast-reacting material. e tried-and-true GX-7 has been a workhorse of the roofi ng industry since the 1980s and is still a gun of choice for SPF roofers today. PMC works from the perspective of "designed with the customer in mind "; so when PMC equipment users and distributors communicated the need for a mechanical purge gun alternative, a project was initi- ated. Recognizing the proven design, the engineers focused on improving critical part tolerances and overall durability. e heart of the PX-7 mechanical purge gun is the module, valving rod and packings. ese are the most criti- cal parts for consistent operation—considering that this is where reactive chemicals meet, are heated to 120 °F and pressurized to 1,000 psi! * If the part measurements and surfaces are not consistent, it can lead to leaking and cross- overs in the gun head. PMC worked to tighten these critical tolerances and put quality measures in place to assure consis- tency in all outgoing parts. Durability of the hardware is where an investment pays off . e hardened stainless gun block and machined coupling block are upgraded to stand the test of time and the removal and reassembly that will happen in an industrial environ- ment. It is this attention to detail that takes a good design to a greater level, a goal attained with the PX-7. Sources ¹ (https://coatingspromag.epubxp. com/i/537615-jul-2015/34) and Roofi ng (https:// w w w.roofi iconic-mercedes-benz-superdome-in-new-orleans-sports-its-bright- est-look-yet) *temperature and pressure settings vary across material formulations and ambient conditions Polyurethane Machinery Corporation One Komo Drive Lakewood, New Jersey 08701 732-415-4400 By Murphy Mahaff ey, Director of International Sales Polyurethane Machiner y Corporation Company Profile: Polyurethane Machinery Corporation—PMC

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