| Connect Follow us on Twitter Like us on Facebook
About | Subscribe | Advertise


Download our free Bridge Coating Systems eResource Book

Problem Solving Forum

| More

October 8 - October 14, 2012

What differences in performance and speed do you see among plural-component, conventional airless, and conventional air spraying equipment for field painting structural steel?

More items for Coating Application

Selected Answers

From Charles Williams of kurbtblast on October 8, 2012:
     Difference are with capacity (gpm) and number of passes for adequate millage.

From Giuseppe Santagata of NACE Certif. Coat. Insp. level III # 2737 on October 9, 2012:
 Plural component requires  very expensive equipment, but it is fast with good production, and saves a lot of paint material, etc. This equipment needs a professional operator, especially to be sure to  obtain the correct mix ratio at the tip. Airless is 100% fast with very high production, but in some circumstances you have also 80% of paint loss if not set properly (pressure tip size and angle) and you need professional sprayers. The air spray or conventional spray is slow, produces a lot of dry/overspray, but has the possibility to work better in some difficul areas, as well as the possibility to clean the surface to be coated immediately before spraying by using the air in the gun.

From Jerry Trevino of Protective Liner Systems on October 21, 2012:
     Plural component pumps are very effective in spraying and applying 100% solid materials and are more productive than (hot potting) airless pumps. Conventional air spaying will not pump high solids, thick coatings. In the case of 50% to 60% solid materials, airless (hot potting) may be more efficient. Conventional spraying may be more efficient in applying thin, one to three mils of a top coat for uv protection or for an aesthetic coat over thicker coats of paint on the structural steel. All three types of spraying have their pro's and con's. Plural component spray systems have a high risk of being off ratio. Temperature adjustments may have to be made to attempt to equalize the viscosity of both components. In some cases, for instance, you must heat one of the two components more than the other. Fast-setting materials may only be sprayed with plural systems. The size of the project, location, overspray considerations, target paint thickness, and type of coating used are factors that have to be considered in selecting the type of spraying to be used.

From Jay Barstow of Aeroflor Coating Services on October 16, 2012:
     Definitely, single-component airless hot potting a low-viscosity, solventless resin for DFT/sec/SF application. It's a function of viscosity and heat. I have shot over 3 GPM from single King airless for hours at a time on large flooring projects. Heat, especially in plural component, affects viscosity and flow, but because of internal mixing,  the effective pressure, and thus flow rate, is lost.

From Daniel Liu of APC on February 6, 2013:
    Plural component equipment is very expensive, but easy for operation during  coating application once the mixing ratio is set. Especially for those materials that include more than two parts, it can be faster and safer.
      Airless spray equipment is the most common equipment used on site. For  materials with high volume solids and higher total thickness sprayed on large areas, airless spray will be required, as it is faster and more convenient. Since the liquid is pressured without air, there is less chance of air entrapment in the coating film, which is very common in the shipbuilding coating field.
     Air spray is normally  used in the field where the thickness is mainly less than 100 microns. The coating material is atomized with pressured air, then blown out together with air to the substrate.  The air pressure is not strong enough to convey high solids materials, so air spray is normally used with very low solids and  low viscosity coatings.

Please sign in to submit your answer this question    

Tagged categories: Air spray; Airless spray; Paint application; Plural component spray; Steel

Current PSF Question | Submit a PSF Question | Full PSF Archive

Commercial Sand Blasting & Painting Ltd.
Reliable Service & Superior Workmanship

We’re ready to meet any of your protective coating and lining needs. We can work on your site or in our facilities, with large shops (60,000 sq ft), 40 acres of yard space, and cranes and forklifts on site.

SSPC: The Society for Protective Coatings
SSPC 2016 Register Now!

SSPC2016 is earlier this year, don't forget to book your plane tickets and hotel. See you soon. For more information visit

SABRE Autonomous Solutions
Safety, Productivity, Quality. Robotic Blasting

Learn how this simple to use, field deployed, automatic robot is eliminating hazards in major confined, cluttered and complex surface preparation projects.

Graco Inc.
Graco Mortar Pump

The M680 sprays epoxy-based mortars, anti-skid coatings, cementitious and filled materials. Compact.
Easy to use.
Call 877-844-7226 or

Built for Tough Jobs

From Epoxies to Urethanes to other high solid coatings, the new Binks Airless 75 delivers a great finish using an ergonomic design. Visit for more information.

ITW Binks
Built for Tough Jobs

From Epoxies to Urethanes to other high solid coatings, the new Binks Airless 75 delivers a great finish using an ergonomic design. Visit for more information.

Apex Waterjetting Technologies
Waterjetting – Custom Manufacturing and Wholesale

• Waterjet Accessories
• Saphire Nozzles
• UHP Hoses
• Replacement Parts
• Wholesale Direct
• 24 Years of Experience
• Buy and Save!!!

JAD Equipment Co.
Trak Mats: Don't get Stuck In the Mud

Trak Mats offer more than just plywood. Use over and over for years.

IBIX North America
Portable Powder Coating System

All-in-one skid mounted system for on-site repairs. Durable coating for industrial, structural steel, pipeline and marine applications. 727-322-4611

Termarust Technologies
Termarust (HR CSA) Chemically Stops
Active Corrosion

Truss bridge treated in 2000 with Termarust's (HR CSA) field-proven rust mitigation system chemically stopped corrosion, crevice corrosion & pack rust.

Technology Publishing

The Technology Publishing Network

The Journal of Protective Coatings & Linings (JPCL) PaintSquare
Durability + Design Paint BidTracker

EXPLORE:      JPCL   |   PaintSquare News   |   Interact   |   Buying Guides   |   Webinars   |   Resources   |   Classifieds
REGISTER AND SUBSCRIBE:      Free PaintSquare Registration   |   Subscribe to JPCL   |   Subscribe to PaintSquare News
MORE:      About   |   Privacy policy   |   Terms & conditions   |   Site Map   |   Search   |   Contact Us

© Copyright 2000-2015, Technology Publishing / PaintSquare, All rights reserved
2100 Wharton Street, Suite 310, Pittsburgh PA 15203-1951; Tel 1-412-431-8300; Fax 1-412-431-5428; E-mail