Grab

For other uses, see Grab.

Tipper with grab loader

A grab is a mechanical device with two or more jaws (also called clamshells), used to pick things up or to capture things. Some types include:

• Roundnose grab
• Clamshell grab
• Orange-peel grab
  • in Dutch they are called poliep grijpers = "polyp grabs".

There are different ways of open/close the grabs:

• electro-hydraulic / diesel-hydraulic
• mechanical by rope(s) (1-rope, 2-ropes, 3-ropes, 4-ropes)

Usage

Grabs can be used for:

• dredging & gravel pits
• bulk handling (e.g. loading/unloading ships)
• salvage (e.g. ship-wrecks, oil)
• excavation (e.g deep shafts)
• street works (e.g Lorry loader grabs)

Manufacturers

The British firm of Priestman stated building grabs for dredging in the late 19th century and then developed a range of Draglines and Front Shovel Excavator and Cranes to operate them.

See also

• Glossary Index

External images

• Big 2-jaw grab used for heavy salvage at sea of the MV Tricolor
• Shelf-Basin Interactions / bottom grab recovery
• Grab with 6 claws
• 2-jaw clamshell grab
• Grab for picking up and weighing big coils of wire
• Different grabs, electro- hydraulic
• Big grabs, special constructions