Marine Crane Anti-corrosion Guide: From Material Selection to Maintenance to Extend Equipment Life!

Corrosion - The "Invisible Killer" of Marine Equipment

In the Marine environment, cranes face three major threats:

Salt spray corrosion: Chloride erodes the metal surface

Electrochemical corrosion: When different metals come into contact, a galvanic cell effect is produced

Biological attachment: Barnacles and algae accelerate structural aging

Material Showdown: 316L Stainless Steel vs. Hot-Dip Galvanized Steel

"316 Stainless steel"

Anti-corrosion principle: A passivation film is formed by chromium-nickel alloy

Salt spray test: No red rust for 5000 hours (ASTM B117)

Cost: High (about twice that of galvanized)

Applicable parts: Hinge points/key load-bearing structures

Hot-dip galvanized steel

Anti-corrosion principle: Zinc layer sacrificial anode protection

Salt spray test: White rust appears after 2000 hours

Cost: Low

Applicable parts: Frame/non-moving parts

BOB-LIFT scheme:

✔ Mixed use - 316L for key parts (such as slewing bearings), and hot-dip galvanizing for others

✔ Enhanced galvanized version - 150μm zinc layer + sealing coating (up to C5-M anti-corrosion grade)

Salt Spray Test data Speaks for Itself

We simulate a five-year accelerated experiment of the Marine environment:

Ordinary carbon steel: Large-scale rusting occurs within 72 hours

Hot-dip galvanized steel: The zinc layer begins to be consumed after 2000 hours

316L stainless steel: Retains metallic luster after 5000 hours

Three DOS and Three Don 'ts" for Daily Maintenance

Must be done

Weekly fresh water rinse: Focus on cleaning welds and bolt gaps

Monthly lubrication: Use NLGI Grade 2 marine grease

Quarterly inspection: Monitor the zinc coating loss with a thickness gauge

Strictly prohibited.

Remove rust violently with a wire brush (damage the protective layer!)

Mixed use of copper-based/aluminum-based lubricants (causing electrochemical corrosion)

Ignore small rust spots (which can spread to structural components within 3 months)

Highlights of BOB-LIFT Marine Customized Models

Provide exclusive solutions for different sea areas:

Tropical sea areas: anti-algae coating + ventilation design

Polar sea area: -50℃ low-temperature hydraulic oil formula

Oil and gas platforms: Explosion-proof certification + flame-retardant cables

Click on our product - Marine Crane page to learn more about the product details!