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Contract Mfg. | Metal Finishing

Stainless Finishing

Apache Stainless Equipment Corp., located in Beaver Dam, Wisconsin, offers in-house pickle passivation and electropolishing services.

metal finishing

Pickle passivation is the immersion of metal in a nitric-hydrofluoric acid bath. Pickled stainless material has a light matte appearance. Benefits include ease of sterilization and corrosion resistance.

Electropolishing is the immersion of metal in a charged bath of sulfuric and phosphoric acid. Benefits include ease of sterilization, improved cleaning properties, corrosion resistance and a mirror finish look.

Apache is a manufacturer of small and large vessels and food processing equipment. We can handle small parts or assemblies as large as our tanks that we build, with larger pieces possible with the use of fixtures or double dipping.

We also offer custom contract manufacturing services. Consider Apache from fabrication and assembly to material finishing for your outsourcing needs.


Passivation and Electropolishing Services at Apache Stainless


How big is the passivation tank?

Our tank measure 20 ft. long x 5.5 ft. wide x 6 ft. deep. Projects over that size limit may be passivated with two dips or a hand spraying option.

What is the difference between pickling and passivation?

Passivation is the removal of excess iron or iron compounds from the stainless surface. No actual metal is removed during passivation. Pickle passivation is the immersion of metal in a pickling bath such as nitric-hydroflouric acid. The process removes metal such as impurities and heat marks from welds.

What is electropolishing?

Electropolishing is an electro-chemical process that removes surface material from stainless steel. This process typically starts with an immersion of the component into controlled bath of electrolyte that is charged with a DC power supply. The finish has a mirror appearance. Apache’s before and after tests have shown improvement in RA (roughness average) up to 50% smoother, depending on the material.

What is electroplating?

Electroplating is the process of plating one metal onto another by hydrolysis, most commonly for decorative purposes or to prevent corrosion of a metal. There are also specific types of electroplating such as copper plating, silver plating, and chromium plating.

What is the difference between Pickle Passivation and Electropolishing?

The main difference between pickle passivation and electropolishing is the appearance and RA (roughness average) of the stainless material. In the photo, an electropolished sample is shown above a pickle passivated sample. The pickle passivated sample has a white appearance, while the electropolished sample has a mirror-like, shiny finish.

Does Apache electroplate?

No, our in-house surfaces include passivation, pickle passivation, electropolishing and mechanical polishing.

What is our lead time for Electropolishing and Passivation?

Our lead time is typically 7 - 10 days for average projects, depending on our production schedule. On large orders we will quote you a time frame for delivery. We will expedite your order for a fee.

What are your size capabilities for electropolishing?

Our EP tank size is 7 ft. long x 6 ft. wide x 5 ft. deep. For components that don’t fit in our tank, we build fixtures for products that allow us to perform electropolishing without dipping the product.

What size heads can you fabricate?

We can fabricate Heads, anywhere from 30” (2’6”) to 192” (16’) Diameter, with the thickness being 12 ga. to ¾” Stainless and up to 7/8” Carbon.

What is the tonnage on Apache's brake press?

350lbs. up to 14 ft.

What are Apache's laser capabilities?

Our laser can take sizes from 60” X 156” up to ½” plate Carbon, Aluminum, or Stainless Steel.

What are your laser cutting capabilities?

We utilize a Strippet/LVD Impuls 4000 watt laser cutting system that can handle pattern sizes of 120" x 156".

What are Apache's welding capabilities?

We do everything from small weldments and general welding to heavy gauge welding. Our tenured welders are ASME certified.

How do I know if you can work on my project?

We can look at drawings, explanation of work to be done and discuss options with you.

What are your Gantry Drilling capabilities?

Our NC controlled Gantry Drilling machine is capable of drilling part and weldments within 96" x 96" x 20".