How to reduce rework when spraying fireproofing

Graco’s XM PFP technology is used worldwide to mix and spray intumescent coatings. They incorporate a range of components that have been specially selected for this application.

High-pressure pumps are typically employed to force the viscous materials through lines. In addition to being composed of 100% solids, intumescent materials containing fibers to reinforce the coating, can require up to 6,000 psi pumping pressure to convey the material.

Heaters bring component material to proper temperature before pumping. At ambient temperatures, intumescent epoxy materials are too thick to pour from the container. In order to condition the material and properly feed the metering pump, the material must be both heated and agitated under pressure.

A heated manifold also helps to provide consistent coating temperatures in cold climates.

Spray tips are also tailored to high-viscosity materials. Tips are typically identified by a three-digit code. The first number, when multiplied by two, indicates how wide of a fan will result when sprayed at a distance of 12 inches from the surface. The other two numbers indicate the orifice size of the tip, in thousandths of an inch. For example, a 535 tip will spray a 10-inchwide fan and have a 0.035-inch orifice. The combination of fan width and orifice size determines coating thickness. Where spraying standard protective coatings typically employs orifices of less than 0.025 inches, intumescent epoxy coatings typically require orifices in the 0.035–0.039-inch range.

Plural-component PFP equipment also typically employs larger hoses and valves than non-PFP equipment. Hoses are typically ¾ inch in diameter. Dosing valves and ball valves are sized to allow a proper flow of both components. The static mixer has a ¾-inch interior diameter and the spray gun also has larger fluid porting than a standard airless gun.

For more details of Graco’s XM PFP technology, fill in the contact form and our specialist will contact you, to discuss which of our products meets your specific application requirements.