Tier 1 Automotive Supplier's Experience with Carbon Steel Filters

CASE STUDY

A large tier 1 automotive plastics molder in the Midwest needed to improve cooling water quality for its molding machines. The decision was made to install bag filters because of the ease of operation and filtration flexibility (ability to change the micron level of filtration by changing bags). At the time of purchase, the price of the carbon steel filters were perceived to be lower than the stainless steel filters. After 2 years of service the filters began to leak, due to severe corrosion, at the lid and developed numerous leaks on the housing body.  Repairs to the corroding units were ongoing, and patches were necessary to continually repair leaks.

Ultimately, catastrophic corrosion failures of the vessel body and discharge lead to the replacement of the carbon steel filters with Filter Sciences stainless units. The cost of repairs to the carbon steel units including; painting, welding, patches and eventual replacement was 3-4 times the original cost of stainless units. This is Not taking into account the down time and negative impact on production.

The "cheap" carbon steel filters ended up costing much more in the long run!

Severe Corrosion on a Carbon Steel Cooling Water Filter in 2 Years                          Customer Welded Patch on Carbon Steel

Carbon Steel Vessel Body is Compromised from Corrosion                                         Carbon Steel Discharge Failure from Severe Corrosion

IMPROVED R.O.I. WITH STAINLESS STEEL

Stainless steel offers superior corrosion-resistance and strength over carbon steel. With the addition of chromium (10.5 to 11 percent by mass), the steel forms a chromium oxide layer to greatly reduce corrosion. The ability to reduce corrosion extends the service life of the filters exponentially and increases your return on investment.

The choice is yours; corrosion, ongoing maintenance, repairs and down time with carbon steel or, the excellent corrosion resistance, low maintenance, extended service life, and  increased ROI of STAINLESS STEEL.

Just say NO to Carbon Steel Corrosion!

What’s the Difference Between 304 and 316 Stainless Steel?

Both 304 and 316 stainless steels are popular grades used in a variety of applications, but they have some key differences:

1. Composition:
   • 304 Stainless Steel: Contains 18% chromium and 8% nickel. It’s commonly referred to as 18/8 stainless steel.
   • 316 Stainless Steel: Contains 16% chromium, 10% nickel, and 2% molybdenum. The addition of molybdenum enhances its resistance to corrosion.
2. Corrosion Resistance:
   • 304 Stainless Steel: Great general-purpose corrosion resistance, but it can be susceptible to chloride-induced corrosion (like in saltwater environments).
   • 316 Stainless Steel: Superior corrosion resistance, particularly against chlorides and marine environments, due to the molybdenum content.
3. Cost:
   • 304 Stainless Steel: Generally less expensive than 316 due to the lower alloy content.
   • 316 Stainless Steel: More costly because of the added molybdenum and better corrosion resistance.

The increased nickel content and the inclusion of molybdenum allows for 316 stainless steel to have better chemical resistance than 304 stainless steel. It’s ability to resist acids and chlorides, including salt, makes grade 316 ideal for chemical processing, marine applications & oilfield produced water.

However, the addition of nickel and molybdenum also makes grade 316 a more expensive alloy than stainless steel 304 per ounce of material.

Though the stainless steel 304 alloy has a higher melting point, grade 316 has a better resistance to chemicals and chlorides (like salt) than grade 304 stainless steel. When it comes to applications with chlorinated solutions or exposure to salt, grade 316 stainless steel is considered superior.

Three Benefits of Using 316 Stainless Steel

1. Corrosion Resistant Properties

 Due to the addition of molybdenum, grade 316 stainless steel is more corrosion resistant than similar alloys, such as 304 stainless steel. This reduces pitting from chemical environments and allows grade 316 stainless steel to be used in highly acidic and caustic environments that would otherwise eat away at the metal. For instance, grade 316 stainless steel can withstand caustic solutions and corrosive applications such as produced water or any other corrosive chemistry.

These properties also make grade 316 stainless steel ideal for pharmaceutical and medical applications. Since sterilization processes in these industries combine both strong disinfectants and or with high temperatures to prevent contamination, a resistant alloy such as grade 316 is ideal.

2. Marine, Chemical & Produced Water Applications

Saltwater and salt air can be especially damaging to metals. Besides the rough environment of the sea and marine applications, chlorides, such as salt, can eat away at even the toughest metals. Salt will even compromise the protective oxide layer of grade 304 stainless steel, resulting in rust.  For marine applications, or processes involving chlorides, grade 316 stainless steel is ideal. Produced water often has 4-5 times more chlorides than seawater.

Grade 316 has especially better resistance to salt and chloride pitting. Pitting corrosion can occur when stainless steel alloys, such as grade 304 stainless steel, come into contact with salt-rich sea breezes and saltwater. Chloride resistant metals, like grade 316 stainless steel, are essential to use for naval applications or anything involved with high chlorides (such as produced water) or chlorine.

3. Lasting Durability

Grade 316 stainless steel is both tough and versatile, which makes it ideal for bag filter housings built to last for years of use under an extremely corrosive environment.

Is It Worth the Extra Cost?

If you have an application with very powerful corrosives or relies on chlorides, then paying a premium for grade 316 stainless steel is definitely worth it. In such applications, 316 stainless will last many times longer than grade 304 stainless steel would—which can mean many extra years of useful life and improved ROI.

However, for applications using milder acids or where salt exposure isn’t a concern, 304 stainless steel alloy can work just as well.

Just be sure you’ve accounted for all processes and environmental factors when choosing a filter bag housing.

Overall, 316 can be worth the expense if you need to have superior corrosion resistance. For many other applications, grade 304 stainless steel will serve perfectly fine. Call and speak with one of our Field Engineers to discuss which grade of stainless is best for your application.

Compatibility Charts

304 Stainless Steel - 304SS Compatibility Chart                         316 Stainless Steel - 316SS Compatibility Chart

VALUE ENGINEERED WITH THE QUALITY OF STAINLESS STEEL

Contact Filter Sciences today to discuss your filter needs and discuss your options. We have a wide range of stainless steel filters to meet your needs and our prices are very competitive with carbon steel. Call today to improve your ROI with Stainless Steel Housings.