In Southeast Asia’s fast-growing industrialization, wastewater treatment facilities face increasing loads. This is especially true for electronics manufacturing and textile industrial parks. Their industrial wastewater contains massive fine particles and heavy metal viscous substances. These materials easily form hard sediment layers at the bottom of sedimentation tanks. Traditional suction pumps clog very easily. Therefore, mechanical grabbing becomes the key link to guarantee continuous system operation. Recently, we customized a large-span overhead crane system for a large industrial wastewater treatment plant in Bac Ninh Province, Vietnam. The core component adopts a clamshell grab specially designed for high-viscosity sediments.
Onsite Challenges: Extreme Sediment Characteristics and Tropical Climate
This wastewater treatment plant faced challenges completely different from the past. The local climate is a tropical monsoon climate. It features high temperatures and high humidity all year round. The wastewater contains massive industrial fiber impurities. These fibers mix with sludge to create extreme toughness. Common grabs often fail to cut in effectively due to tangling or slipping. Furthermore, because the park has a massive treatment volume, the clamshell grab system requires high-frequency continuous operation 24/7. This posed a severe test for the reliability of the overhead crane.
Customized Solution: High-Performance Clamshell Grab
To address the special working conditions of the Bac Ninh plant, we reinforced the overhead crane main body. More importantly, we made targeted localized upgrades to the structure of the clamshell grab.
Technical Parameter Configuration
We treated the cutting force and sealing performance of the clamshell grab as core design indicators:
|
Parameter Item |
Technical Indicator |
| Grab Type | Hydraulic Rotating Clamshell. |
| Safe Working Load (SWL) | 8 tons. |
| Self-Weight | 3.8 tons. |
| Grab Volume | 3.0 cubic meters. |
| Material | Swedish Hardox wear-resistant steel plate + reinforced cutting edge. |
| Power Output | High-torque hydraulic rotary motor. |
| Special Protection | IP66 protection rating electrical system + anti-tropical fungus coating. |
Clamshell Grab Design Highlights
●Reinforced serrated cutting edge: To handle industrial fiber tangling, we added special hard alloy serrations to closing edges. This design cuts through fiber impurities at the moment of closure. It ensures the grab bites directly into bottom sludge, solving the slipping problem.
●High-response hydraulic rotation system: Considering the narrow sedimentation tank space, we designed the clamshell grab to rotate 360 degrees continuously. Operators achieve precise cutting angle adjustments from the cabin. This avoids tank walls and mixing equipment, significantly raising the safety factor.
●Tropical climate adaptability design: Given the high-temperature environment in Vietnam, we selected a large-capacity hydraulic cooling system. We upgraded all seals to fluororubber. This prevents hydraulic oil deterioration and sealing ring aging leakage caused by high temperatures.
Operational Effectiveness
Since the system went into operation, the cleaning efficiency of Bac Ninh plant’s sedimentation tanks rose by nearly 40%. More importantly, because the grab’s cutting performance is outstanding, bottom sediment is cleared more thoroughly. This avoids sludge fermentation that generates excessive foul gas, greatly improving surrounding environmental quality.
This project proves again that there is no universal equipment in the wastewater treatment field. Only customized designs for specific working conditions work best. Through deep optimization for material properties like fiber content and climate factors, we transform traditional overhead cranes into core productivity.