Graco Inc.

Plural component coating system on a big oil valves

RI-ME Sabbiatura & Verniciatura was contracted to coat big steel valves for the oil industry. Due to the intense corrosion this industry faces, a 100% solids material has been selected for this job. This contractor needed an easy to use machine with fast set-up and clean up times in order to generate a quick return of investment, providing overall high quality results.

This case describes the spraying of big valves and components used in the oil refinery industry with a 3:1 3M coating system using a Graco mechanical proportioner XP70.

The selected fast-curing material, the 3M Scotchkote Urethane Coating 352 HT, doesn’t need a primer, contributing to save money and time in the coating application. Due to its fast curing property at 60 °C, this material needed a specific configuration, with a proportioner able to keep the right mix ratio required, different heated zones, a remote mix manifold, a recirculation on A side and a customized feeding system from the 2 drums.  

XP70 for handling a fast curing material

The right configuration was found by the Graco protective coating distributor Verve.
A Graco XP70 mechanical proportioner has been selected, at 220 bar dynamic fluid pressure, with only one Viscon heater on A side and a specific water jacked heated hoses system up to the mix manifold. The feeding system has been configured with a piston pump on drum A and a gravity system on drum B inside the hopper. The mixing system of the Graco XP70 is the right one for handling a fast curing material at the required temperatures.

Saves time,  pre-mixed coating & solvent

The specific application of this coating, with 650/750µm thickness, has been realized with a significant time saving  (30-40% less compared to an old proportioner), a strong saving of pre-mixed coating  (25%) and an impressive quantity of solvent saved (50%). As a result, Ri-Me will enjoy a return on investment of less than 18 months.