Regarding the rust prevention methods for explosion-proof manual hoist carts, combined with their special application scenarios and corrosion reasons, systematic protective measures can be taken from the following aspects:

1、 Analysis of Corrosion Mechanism

Material characteristics

Explosion proof hoists are mainly made of copper alloy materials such as aluminum bronze and beryllium bronze. Although they are not prone to rust, long-term exposure to humid environments can still form copper rust (alkaline copper carbonate), resulting in a decrease in surface roughness and an increased risk of friction sparks.

Environmental incentives

Chemical corrosion: Sulfides and acidic gases (such as H ₂ S, HCl) in petroleum and chemical environments can react with copper alloys.

Electrochemical corrosion: The formation of micro battery effects in humid environments accelerates the precipitation of metal ions.

Mechanical damage: Collision or friction damage the surface oxide film, exposing the active metal layer.

2、 Rust prevention strategy

1. Surface protection enhancement

Coating upgrade

Using explosion-proof certified epoxy powder coating or fluorocarbon paint instead of ordinary paint to enhance weather resistance and chemical stability.

Coating treatment

Key components such as hooks and chains can be electroplated with nickel phosphorus alloy or zinc nickel alloy to isolate corrosive media.

2. Control of homework environment

Humidity management

In refineries, oil depots, and other places, dehumidifiers are used to control the environmental humidity to ≤ 60%, or temporary rain shelters are built to prevent equipment from getting wet.

gas monitoring

Equipped with a portable hydrogen sulfide detector, suspend operation when the concentration is greater than 10ppm to prevent corrosive gases from accelerating corrosion.

3. Daily maintenance standards

Cleaning process

After each use:

① Wipe the surface with anhydrous ethanol to remove grease and corrosive residues;

② Soak the chain in anti rust oil (such as T921 anti rust oil) for 5 minutes, let it dry, and then apply lubricating grease;

③ Stored in a sealed explosion-proof cabinet, with silicone desiccant placed inside the cabinet (≥ 2kg per 1m ³ space).

regular inspection

Weekly inspection:

① Does the elongation of the chain pitch exceed 3% of the original length;

② Whether the wear of the dangerous section of the hook exceeds 10%;

③ Is the thickness of the brake friction plate less than the minimum allowable value (usually 50% of the original thickness).

4. Lubrication and rust inhibitor selection

chain lubrication

Choose food grade grease (such as Krupp LDS 18 Special A) that meets ATEX explosion-proof standards to avoid dry friction caused by insufficient lubrication.

Long term rust prevention

Spray WD-40 rust inhibitor (certified by Ex) on the equipment every quarter to form a dense protective film with an effective period of up to 6 months.

5. Emergency repair measures

Localized corrosion treatment

If the chain shows spot rust:

① Polish with 120 grit sandpaper until a metallic luster is exposed;

② Spray zinc based cold galvanizing spray (thickness ≥ 80 μ m);

③ Conduct a dynamic load test at 50% rated load to verify the repair effect.

Deep corrosion treatment

If the corrosion depth of the hook neck exceeds 5% of the nominal diameter, the original explosion-proof certified accessories must be replaced immediately, and welding repair is strictly prohibited.

3、 Management optimization suggestions

Establish equipment archives

Record the environmental parameters (temperature, humidity, corrosive gas concentration) and maintenance details for each use, and optimize the rust prevention strategy through data analysis.

Training and Certification

Operators need to undergo training on the "Safety Regulations for Maintenance of Explosion proof Equipment" and obtain a special operation qualification certificate to ensure compliance with rust prevention operations.

Spare parts Management

Reserve key vulnerable parts (such as chains and hooks), and spare parts must be certified by ATEX or IECEx to avoid the use of non explosion proof alternatives in emergency situations.

The main equipment produced by Hebei Makita: stage electric hoist, electric chian hoist, wire rope electric hoist，Hand chain hoist, lever hoist, pneumatic hoist and other lifting equipment