6 Advanced Cleaning & Stripping Chemistries For Flight Critical Parts

Cleaning and stripping of metal parts is possible through a variety of physical and chemical techniques. Both sandblasting and a bath in a paint stripper can accomplish the same goal — removing paint — but there are differences. 

A chemical dip gets into places that physical media simply can’t, and it also won’t risk abrasive damage or warping of the metal. In certain applications, blast media may have advantages that will make that process the better choice. It all comes down to the part and the desired result. Let’s take a closer look at the chemical side of things.

Cleaning & Stripping Chemistries For Flight Safety Critical Aircraft Parts 

Flight safety critical aircraft parts (FSCAPs) demand a high standard of attention and reliability. These parts must be maintained in peak condition to ensure the security of every flight. This means absolute compliance with standard practice operating procedures (SPOPs) and optimal chemistries during refurbishment processes at MRO facilities.

Chemical cleaning and stripping is the most thorough way to remove paint, rust, corrosion, and contaminants from the surface of flight critical metal components. Here are six of the advanced chemical processes we commonly use in refurbishing and restoring your FSCAPs for extended part life and a return to service.

1) SPOP 18 — One-Step Alkaline Rust Remover 

Rust and corrosion are typical targets for chemical removal from aerospace engine components and flight safety critical aircraft parts. This alkaline rust remover process cleans titanium parts and removes these conditions in a one-step chemical bath per SPOP 18.

2 ) SPOP 203 — One-Step Alkaline Rust Remover Long Soak

SPOP 203 is the long soak variation of the process for removing alkaline rust. When scale and other surface conditions are more severe, this single-step method involves soaking in alkaline rust removal solution at near boiling temperatures for 30-90 minutes. Afterwards, a water rinse cleans the solvent from the part.

3) SPOP 208 — Degreasing of Parts By Solvent Wiping

Grease, oil, and other contaminants can be removed via direct wiping with a solvent or cleaner under SPOP 208 at qualified MRO facilities. Degreasing is sometimes necessary before other cleaning, stripping, or finishing processes can be completed.

4) SPOP 209 — Degreasing of Parts by Aqueous Cleaning

The aqueous degreasing method involves a more comprehensive clean process rather than targeted wiping, when grease must be more thoroughly removed from a part. This is sometimes necessary before a rust removal bath or paint strip procedure can be completed.

5) SPOP 211/ 213 — Multi-Step Heavy Duty Cleaning & Descaling

This multi-step cleaning and descaling procedure involves a four-step alkaline rust removal and acidic descaling process (SPOP 211) involving inhibited phosphoric acid. The SPOP 213 portion refers to the heavy duty cleaning and descaling that is completed without inhibited phosphoric acid.

6) SPOP 317 — Acidic Peroxide Stripping of Plasma Coatings 

This is a stripping process rather than a chemical cleaning process. Tungsten carbide coatings are commonly used in FSCAPs and other aerospace parts for corrosion resistance, abrasion resistance, and hardness. Removal of this coating is therefore difficult, and requires a specialty acidic peroxide stripping procedure in accordance with SPOP 317.

The SPOPs above are only a partial list of the capabilities at our MRO facilities for cleaning and stripping, which also extend into abrasive blast and plating applications. Typically, cleaning processes occur first, as preparation, and stripping processes for additional coating removal (as with grit blasting) will follow after.

It’s critical that damage is not done to the part during these techniques. The right advanced cleaning and stripping chemistries get the job done both efficiently and safely. Metal Finishing Technologies LLC has been a certificated FAA Repair Station since January 1991. We carry out more than 20 processes that meet strict repair specifications for fans and hubs, turbine shafts and vanes, gears, disks, combustors, and more.

Get in touch with the MFT team or request a quote today for expedited quoting, industry-best turn-around times, and the highest quality performance in MRO cleaning & stripping chemistries for flight critical parts!