Grab Buckets

In 1967, FUKUSHIMA became the first in Japan to manufacture and deliver authentic hydraulic grab buckets.
Since then, we have manufactured over 3,000 units of grab buckets - electro-hydraulic and diesel-hydraulic types.
These grab buckets are working night and day at waste disposal facilities and are used for cargo-handling operations at ports throughout Japan.
We developed a patented energy-saving electro-hydraulic grab bucket.
Numerous customers, including the waste disposal special district authority for the 23 wards of Tokyo, find our grab buckets very useful and efficient.

Grab buckets are introduced into many waste disposal facilities in Fukushima, as well as Tokyo and all major cities.
Additionally, we have developed a global environment protection type (CO₂ reduction type) for grab buckets for waste disposal facilities, and have obtained patent No. 3792709.
(Please see "Energy-saving electro-hydraulic grab buckets" for details.)

Our grab buckets are applied to loading operations for bulk cargo at ports.
Especially, engine grab buckets with installed diesel engines have a good reputation because they can be operated without power cables.

The single-rope grab bucket is a truly eco-friendly grab bucket as it does not need any power source and is operable simply by being craned.
Its simple structure (meaning fewer parts and components), ease of maintenance and remote control of bucket-opening action allow this type of grab bucket to conduct remote operations safely - its foremost feature.
Grab buckets of this type are mainly used to handle cargo operations at ports.

In 1989, Fukushima developed a diesel hydraulic grab bucket for lumber in order to lower the amount of risk involved in lumber loading operations at ports.
This type of grab bucket is equipped with a special fan in order to turn its direction.
Directional changes can be controlled by radio control, therefore, this grab bucket has a good reputation because this bucket can also keep operations safe and improve loading efficiency greatly.
Up to now, more than 500 grab buckets for lumber have been delivered in Japan. They help loading operation at ports in each place.

Our hydraulic grab bucket can grab many kinds of bulk cargo tightly because our grab bucket can open and close by hydraulic power, and our grab bucket is lighter than mechanical buckets.
Therefore, that makes loading operations more efficient.
We provide two types of grab buckets, an electric type and diesel type, and we can satisfy a large variety of loading purposes and crane types in order to deal with many kinds of cargo between 1m³ and 20m³.

Grab buckets with installed gear pumps previously had a problem in which high heating generation caused the overheating of working oil.
However, the introduction of an axial piston pump has improved this problem.
Energy-saving electro-hydraulic grab buckets developed by Fukushima can protect against the overheating of working oil temperatures.
Also, they can cut CO₂ emissions by approximately 28%

Polyp type hydraulic grab buckets with 15kW electric motors have been improved in the following points compared to the old type of grab buckets with gear pumps.

• Reduction in electric consumption: Approximately 28%
• Reduction in CO₂ emissions (per grab bucket): Approximately 3,800Kg-CO₂ reduction per year
• Maximum engine oil temperature: 70°C or less (in case of continuous operation for 24 hours in the summer)
       (Preventing deterioration of engine oil and oil seals, and prolonging hydraulic part life)
• Available in an enclosed type (as an option)
• Improvement of working environments

Grab buckets generally repeat the following operations (one cycle: about 180 seconds total)

1. Standby: Discharging a whole quantity of working oil by low pressure without any operations (about 150 seconds)
2. Opening: Opening the claws with 10Mpa on average (about 10 seconds)
3. Closing: Closing the claws with 15Mpa on average (about 15 seconds)
4. Grasping: Discharging a whole quantity of working oil with 21Mpa (about 6 seconds)

The old type of grab buckets discharged a whole quantity of working oil at each cycle above. However, our energy-saving electro-hydraulic grab bucket with an axial piston pump can cut discharged oil at No. 1 and No. 4 in the cycle.

Gear pump type

Energy-saving type

• Electric consumption of gear pump type: 4.268kWh
• Electric consumption of axial piston pump type: 3.063kWh
• Amount of reduction in electric consumption per hour: 1.205kWh = 4.268Wh − 3.063kWh
• Percentage of electric consumption: 28.2% = 1.205kWh ÷ 4.268kWh × 100
• Amount of reduction in CO₂ per energy-saving grab bucket:
             3,800Kg/year = 0.36 (scale factor) × 1.205kWh × 24h × 365d

This comparison is between the gear pump type and axial piston pump types.
The percentage of reduction in electric consumption and CO₂ can be calculated on the basis of electric consumption before and after introducing the energy-saving type grab bucket with the above formula.