Explosion proof crane, or flame proof crane, is a specialized type of lifting equipment designed for use in hazardous environments where there is a risk of explosions due to the presence of flammable gases. As an experienced crane manufacturer, we offer robust and reliable ex proof crane solutions tailored to meet the stringent demands of these specialized applications, ensuring not only operational efficiency but also the safety of workers and equipment.
Types of Explosion Proof Cranes
Double Girder Explosion Proof Crane
Double girder ex proof cranes feature two parallel girders and are designed for heavier lifting applications. These double girder overhead cranes offer higher lifting capacities and longer spans.
- Lifting capacities range from 5 to 75 tons.
- Enhanced stability and durability.
- Incorporates specialized safety features like flame proof enclosures and spark-resistant components.
Single Girder Explosion Proof Crane
Single girder explosion proof crane consists of a single beam or girder that supports the hoist. These single girder overhead cranes are compact, lightweight, and ideal for lighter lifting requirements.
- Lifting capacities typically range from 1 to 20 tons.
- Compact design allows for efficient use of space.
- Equipped with explosion-proof hoists and electrical components.
Explosion Proof Crane Specifications
| Technical Parameter of AQ-LB Explosion Proof Single Girder Crane | ||||||||
|---|---|---|---|---|---|---|---|---|
| Capacity | t | 1 | 2 | 3 | 5 | 10 | 16 | 20 |
| Span | S(m) | 7.5~31.5 | 7.5~31.5 | 7.5~31.5 | 7.5~31.5 | 7.5~31.5 | 7.5~31.5 | 7.5~31.5 |
| Lifting height | m | 6~30 | 6~30 | 6~30 | 6~30 | 9~30 | 9~30 | 9~30 |
| Lifting speed | m/min | 8（0.8/8） | 8（0.8/8） | 8（0.8/8） | 8（0.8/8） | 7（0.7/7） | 3.5（0.35/3.5） | 3.3（0.33/3.3） |
| Trolley speed | m/min | 20(30) | 20(30) | 20(30) | 20(30) | 20(30) | 18 | 14 |
| Crane speed | m/min | 20(30) | 20(30) | 20(30) | 20(30) | 20(30) | 20(30) | 20(30) |
| Work duty | A3~A4 | A3~A4 | A3~A4 | A3~A4 | A3~A4 | A3~A4 | A3~A4 | |
| Explosion-proof Grade | ExdⅡBT4、ExdⅡCT4 | |||||||
| Track type | P18 | P18 P24 | P24 | P24 | P24 P30 | P30 P38 | P30 P38 | |
| Technical Parameter of AQ-QB Double Girder Explosion Proof Crane | ||||||||
|---|---|---|---|---|---|---|---|---|
| Capacity | t | 5 | 10 | 16 | 20 | 32 | 50 | 75 |
| Span | S(m) | 10.5~31.5 | 10.5~31.5 | 10.5~31.5 | 10.5~31.5 | 10.5~31.5 | 10.5~31.5 | 10.5~31.5 |
| Lifting height | m | 6~16 | 6~16 | 6~16 | 6~16 | 6~18 | 6~16 | 6~20 |
| Lifting speed | m/min | 5 | 5 | 4.2 | 4.2 | 4.1 | 3 | 1.9 |
| Trolley speed | m/min | 19.6 | 20.5 | 20.5 | 20.5 | 20 | 19.1 | 10.5 |
| Crane speed | m/min | 22.3 | 22.3 | 19 | 19 | 17 | 19.4 | 15.4 |
| Work duty | A3~A4 | A3~A4 | A3~A4 | A3~A4 | A3~A4 | A3~A4 | A3~A4 | |
| Explosion-proof Grade | ExdⅡBT4、ExdⅡCT4 | |||||||
| Track type | P38 | P38 P43 | P43 | P43 | P43 QU70 | QU80 | QU100 | |
Applications of Explosion Proof Overhead Cranes
Petrochemical PlantsExplosion-proof overhead cranes are commonly used in petrochemical plants to handle volatile chemicals like methane and propane. They are used for transporting raw materials, lifting equipment for maintenance, etc.
Oil and Gas RefineriesIn refineries, where flammable gases are common, explosion proof factory overhead cranes are crucial for moving large components, performing maintenance, and handling equipment during operations.
Chemical Processing FacilitiesChemical plants rely on explosion proof bridge cranes for transferring chemicals, managing storage tanks, and assisting in equipment installation and maintenance.
Paint and Coating FactoriesExplosion proof factory overhead cranes in paint factories handle flammable solvents, mix paint components, and transport materials within production lines.
Energy and Power Generation PlantsExplosion proof bridge cranes in power plants, especially those with gas turbines, are used for installing turbines, lifting heavy equipment, and safely transporting materials.
Mining IndustryIn mining industry, explosion proof cranes are widely used for transporting explosives and other hazardous materials, handling and processing coal, which generates explosive dust, as well as maintaining heavy mining equipment.
What Makes a Crane Explosion-Proof?
The explosion proof overhead crane is built on the foundation of a standard overhead crane but incorporates explosion-proof features into the design. The primary goal is to ensure that sparks, heat, or combustible dust generated by the crane and its working environment do not pose fire or explosion hazards. Here’s an overview of the components that make a crane explosion-proof:
Explosion Proof Electrical Components
- Explosion Proof Motors: These motors are sealed and designed to prevent any sparks or heat from escaping and igniting the surrounding flammable atmosphere.
- Explosion Proof Wiring: Special cables with robust insulation are used, and the wiring is either armored or placed in conduits to ensure that no sparks can escape and ignite the surrounding materials.
Sealed Junction Boxes
All electrical connections and junctions are housed in explosion-proof junction boxes that are tightly sealed to prevent flammable gases or dust from entering and causing an explosion. These boxes also prevent sparks from igniting the environment.
Explosion Proof Electric Hoists
The hoist mechanisms in explosion-proof cranes are built with materials and designs that ensure they do not overheat, produce sparks, or generate friction that could ignite flammable substances. They also use sealed bearings and other components that prevent dust or fumes from infiltrating the system.
Flame Proof Enclosures
The crane’s electrical and mechanical components are often housed in flame proof enclosures that are designed to contain any internal explosions and prevent them from spreading to the environment.
Corrosion-Resistant Materials
Cranes used in explosive environments are often built with corrosion-resistant materials to ensure that the structure remains intact and does not degrade over time, which could lead to potential hazards. This includes stainless steel or specially coated materials that withstand chemical reactions.
Overload Protection and Safety Systems
Explosion proof bridge cranes include overload protection mechanisms to ensure the crane does not operate beyond its safe capacity. This helps to avoid overheating or other failures that could result in sparks or other ignition sources.
Explosion Proof Classification
According to the provisions outlined in Chapter 4 of GB3836.1, cranes are classified into Class I and Class II electrical equipment based on the presence of explosive gas atmospheres. Similarly, as per the provisions of GB12476.1, electrical equipment designed for use in combustible dust environments is categorized into a single class. The corresponding classification of cranes is detailed as follows.
Equipment Classification
- Class I: Cranes designed for use in coal mines.
- Class II: Cranes used in explosive gas environments other than coal mines.
- Dust Class: Cranes intended for use in combustible dust atmospheres.
Class II flameproof (“d”) explosion-proof cranes and intrinsically safe (“i”) explosion proof cranes are further divided into Class IIA, Class IIB, and Class IIC based on the characteristics of the explosive gases. The operating conditions for Class IIB explosion-proof hoists cranes are applicable to Class IIA. Similarly, the operating conditions for Class IIC flame proof eot cranes are applicable to both Class IIA and Class IIB environments.
Dust explosion proof cranes are classified into A-type and B-type based on the dust-proof capabilities of their electrical equipment. The B-type has additional requirements for heat cycle testing compared to the A-type, and they are denoted as DIPA and DIPB, respectively. For example, our AQ-LB type single girder flame proof cranes is recommended to choose electrical equipment with an A-type dust-proof enclosure.
Hazardous Zone Division
Explosive Gas Atmosphere Zones:
- Zone 0: Continuous presence of explosive gases.
- Zone 1: Likely presence of explosive gases during normal operation.
- Zone 2: Rare and short-duration presence of explosive gases.
For example, our AQ-LB single girder explosion proof cranes are suitable for use in Zone 1 and Zone 2 but are not designed for use in Zone 0 environments.
Combustible Dust Atmosphere Zones:
- Zone 20: An area where combustible dust is continuously present or frequently suspended in the air in sufficient quantities to form an explosive atmosphere.
- Zone 21: An area where combustible dust is likely to form an explosive atmosphere during normal operation.
- Zone 22: An area where combustible dust is unlikely to form an explosive atmosphere during normal operations, but, if it does, it will only last for a short time.
Temperature Classifications
The surface temperature of electrical equipment or components in Class I cranes should not exceed:
- 150°C when coal dust may accumulate on the surface.
- 450°C when coal dust cannot accumulate on the surface or when measures have been implemented to prevent dust deposition (e.g., sealing against dust or ventilation).
The maximum surface temperature classifications for electrical equipment used in Class II and dust-type explosion proof cranes are provided below:
- T1 Class: The maximum surface temperature is up to 450°C. This class is suitable for environments with substances like methane and ethane, which have high ignition temperatures.
- T2 Class: Equipment in this class has a maximum surface temperature of 300°C. It is ideal for handling materials such as ethylene and acetone.
- T3 Class: The maximum surface temperature for this classification is 200°C, making it suitable for environments with substances like gasoline and ammonia.
- T4 Class: With a maximum surface temperature of 135°C, this classification is designed for environments handling volatile substances such as ethyl ether and ethylene oxide.
- T5 Class: Equipment classified under T5 must not exceed a surface temperature of 100°C. It is often used in environments with carbon disulfide.
- T6 Class: The strictest classification, allowing a maximum surface temperature of 85°C. It is suitable for environments where materials like hydrogen sulfide are present, which have very low ignition temperatures.
Proper classification ensures the right explosion proof lifting equipment is selected for specific hazardous environments, reducing the risk of ignition and ensuring safety in lifting operations.
Installation and After-sales Service for Explosion Proof Crane
To ensure that our explosion proof cranes perform efficiently and safely, we provide comprehensive installation and after-sales services, tailored to the unique needs of each customer.
Installation Services: Ensuring Safe Lifting in Hazardous Environments
On-Site Installation
Our skilled technicians provide comprehensive on-site installation services, ensuring that every component of your explosion proof crane is correctly assembled and configured, with attention to every detail, such as structural integrity checks, explosion-proof measures, electrical wiring and control system installation, etc.
Online Installation Guidance
For customers who prefer local assembly or have technical teams on-site, we offer remote installation guidance. Through video calls, detailed manuals, and step-by-step instructions, our experts guide your team through the entire overhead crane installation process.
After-Sales Service: Comprehensive Support for Lifting in Explosive Environments
Training Service
We offer training service to equip your staff with the knowledge to: safely operate the explosion proof crane, identify potential hazards, and perform basic troubleshooting and maintenance.
Regular Maintenance and Inspections
We offer scheduled maintenance services to ensure the longevity and reliability of your equipment. This includes: inspecting flameproof enclosures for any damage, checking electrical components for wear and tear, and verifying compliance with explosion-proof standards.
Spare Parts Supply
We maintain an extensive inventory of genuine spare parts, ensuring quick replacements to minimize downtime. From motors and electrical panels to control systems, we’ve got you covered.
24/7 Technical Support
Our team is available round-the-clock to address any issues that may arise. Whether it’s troubleshooting an electrical fault or advising on operational best practices, we’re just a call or message away.
At Aicrane, we are committed to delivering not only high-quality explosion proof cranes but also exceptional installation and after-sales service throughout the lifecycle of your crane. With our expertise, you can rest assured that your lifting operations in hazardous environments remain safe, compliant, and efficient. Contact us today to learn more about our explosion proof crane solutions and services.
