Pole Info Center

Finishing Process and Colors

Leaders in the Field


Powder Coating Finishes for Steel and Aluminum Light Poles provides insight into how powder coating is used on steel and aluminum light poles. The paper concludes with an overview of DWM Holdings’ powder-coating process and suggested maintenance to prolong a powder-coated finish in the field.

All of our products come complete with our state-of-the-art, multi-stage finishing process.

Mechanical and Physical Properties

Adhesion Crosshatch adhesion using .0625″ squares; no failure
Pencil Hardness 2H minimum
Impact Test

150 inch pounds direct

150 inch pounds reverse

Gloss 50%
Salt Fog Testing
2,500+ hours in a 5% solution at 95-degrees F and 95% humidity with no creepage (ASTM B-117)
Humidity 1,000 hours at 110-degrees F and 100% relative humidity
Weathering 95% gloss retention under a sun simulator for 1,000 hours

The finishing process varies depending on the warranty selected, but, at a minimum, all products receive the following:

Stage 1: Cleaning

The overall success of our finishing process depends entirely on the quality of the product at the beginning of the process. All products are first inspected for visible deposits of oil, grease, or other contaminants. Surface imperfections such as sharp fins and edges, weld spatter, or burning slag are removed. Once any visual imperfections have been addressed, the piece is sent to our four-wheel shot blaster system, specifically designed for the cleaning steel and aluminum poles. We use steel shot to remove any rust, mill scale, oxides, or other unwanted particles from the shaft or bracket. Upon exiting the shot blaster, compressed dry air is used to remove any remaining shot. The quality of our inspections, shot, and equipment result in a surface preparation that exceeds the specifications published by the SSPC-SP10.

Stage 2: Phosphate Rinse (Steel Poles Only)

In this stage, the pole is coated with iron phosphate, which creates an iron oxide base followed by a flat or amorphous metal phosphate topcoat. This phosphating, or conversion coating, is a critical part of the pre-treatment process for steel poles, adding significantly to the performance of the finished coating. A phosphate coating converts the metal substrate to a uniform, inert surface, which improves bonding, minimizes the spread of oxidation if the coating is scratched, and improves the overall corrosion resistance of the final part. The phosphate solution sits directly on the pole before being rinsed off prior to the pole going into the dry-off oven.

Stage 3: Powder Coat Application

powder_coating_system1 Powder coating is a durable scratch- and chemical-resistant finish that provides excellent corrosion protection from environmental elements. Powder coating is also an environmentally friendly process that emits nearly zero volatile organic compounds (VOC). Whether it be standard or custom colors, our powder coat finish is one of the finest in the industry.powder_coating_system2

The powder we use is a triglycidyl isocyanurate (TGIC) polyester specially formulated for United Lighting Standards. This formula consists of polymers, pigments, and fillers that form a fine dry powder for electrostatic application. The electrostatic application is performed automatically by the negative charging of the powder at high voltage, low amperage, and electrically grounding the pole. This creates a magnetic effect that enables the powder to be applied consistently and uniformly to all exposed surfaces of the pole. Powder coating provides superior edge coverage and creates a high-quality, durable finish with virtually no drips, runs, or sags.

Stage 4: Curing

Oven_SmWe cure our powder using a unique combination of infrared and convection heat. The pole is heated to temperatures exceeding 450°. When the powder is exposed to this heat, it begins to melt, flows out, and then chemically reacts to form a higher molecular weight polymer in a network-like structure. This curing process, called crosslinking, requires a certain temperature for a certain length of time in order to reach full cure and establish the full film properties for which the material was designed.

Stage 5: Blue Wrap

Once completely cooled, the pole is then wrapped in United Lighting Standards’ signature Blue Wrap—a multi-layered, UV- and tear-resistant, vinyl bubble wrap designed to ensure the products reach the job site in top condition.

Additional finishing stages such as galvanizing and adding an interior rust inhibitor are available through our extended 5- and 10-year warranties.

Standard Color Options

White (WH)

Textured White (TWH)

Dark Bronze (DB)

Harvest Bronze (HB)

Textured Medium Bronze (TMB)

New Bronze (NB)

Silver (SL)

Medium Gray (MGY)

Gray (GR)

Textured Gray (TGR)

Matte Aluminum (MA)

Platinum Silver (PSP)

Black (BK)

Textured Black (TBK)

The color swatches above are meant only as an example and should not be considered to be exact matches. Due to the various monitors and their settings, distortion may occur. Please contact us to request a set of our standard color chips.

Premium Colors

Graphite Metallic (GM)

Dark Platinum (DP)

Moss Green (MG)

Custom Colors Are Available

RAL 1017

RAL 5005

RAL 3014

RAL 8001

RAL 6000

The RAL colors above are for example only. We don't stock these colors, but these are generally readily available for an additional color set-up charge. We can match any color request using the RAL color system. We are happy to work with you to meet any color needs your project requires. Please contact us with questions or to quote custom colors.

About Us

United Lighting Standards has been committed to designing, fabricating, finishing, and packaging high-quality steel and aluminum poles since 1971. We adhere to standards set forth by AASHTO, ASTM International, and NEMA. All of our products are built using fabricating and welding procedures outlined in the American Welding Society (AWS) manual for steel and aluminum to eliminate welding defects and ensure structural integrity.

Read more about ULS