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How to Use the Grab Hammer in Pile Drilling

May 21,2024

Pile drilling is a critical process in construction, providing the necessary support for large structures. Among the various tools used in this process, the mechanical hammer grab stands out for its efficiency and versatility. In this guide, we will delve into how to use a hammer grab in pile drilling, ensuring your project benefits from this powerful equipment.

What is a Mechanical Hammer Grab?

A mechanical hammer grab is a specialized tool designed for the excavation and removal of soil or rock during pile construction. It consists of two hinged jaws that open and close to grab and release material, powered by hydraulic or pneumatic cylinders. This tool is essential for creating deep, stable foundations for various structures.

hammer grab (1)

Step-by-Step Guide to Using a Hammer Grab in Pile Drilling

Preparation and Setup

Site Assessment: Begin by conducting a thorough assessment of the drilling site. Identify the type of soil or rock and any potential obstacles that may affect the drilling process.

Equipment Check: Inspect the hammer grab and all related equipment, including the crane or drilling rig. Ensure that all parts are in good working condition and that the hydraulic or pneumatic systems are functioning correctly.

Safety Measures: Implement safety protocols to protect workers and equipment. Ensure all personnel are trained in operating the hammer grab and understand the safety guidelines.

Positioning the Hammer Grab

Attachment: Attach the hammer grab to the crane or drilling rig using the suspension system. Ensure it is securely fastened to prevent accidents during operation.

Alignment: Position the hammer grab over the exact spot where the pile hole will be drilled. Use the rotary mechanism to align the grab perfectly.

Excavation Process

Double Rope Operation:

Rope Mechanics: During the double rope operation, the rope of a chain suspension tackle of the hammer grab unit is crucial. When lowering the hammer grab into the casing hole, the first rope is lifted, closing the grab jaws. At the required location, the second rope is lifted, and the grab jaws are opened by means of the heavy spring.

Penetration: The brakes of both cable dredger winches are opened, allowing the hammer grab to drop with open jaws, penetrating firmly and deeply into the strata. For maximum filling capacity, the hammer grab can be lifted several times by means of the second rope to penetrate deeper into hard strata with an open jaws chisel effect before being withdrawn with closed jaws by means of the first rope.

Single Rope Operation:

Suspension and Dropping: In single rope operation, the grab is suspended at the closing mechanism and driven into the casing with open jaws. It is freely dropped at the required location, and the grab falls to the casing bottom with the jaws open.

Closing Mechanism: Upon hitting the casing bottom, the latches in the casing cover fall to the outside, and the jaws are closed when pulling the rope attached to the closing mechanism. After withdrawal from the casing, the grab is guided into the chandelier and slowly lowered.

Lifting and Emptying

Material Handling: Once the grab reaches the desired depth and captures the material, lift it out of the pile hole. Move it to the designated dumping area and release the material by opening the jaws.

Repetition: Repeat the excavation process until the pile hole reaches the required depth and diameter. Regularly inspect the hammer grab and other equipment for any signs of wear or damage.

Depth Monitoring: Use depth gauges or other measurement tools to monitor the progress of the drilling and ensure accuracy.

Applications of Hammer Grab in Pile Drilling

Foundation Construction: Essential for creating deep foundations for buildings, bridges, and other large structures.

Marine Engineering: Used in the construction of piles for docks, piers, and offshore platforms.

Infrastructure Projects: Employed in the development of highways, railways, and other infrastructure projects requiring robust foundations.

Using a mechanical hammer grab in pile drilling is a reliable and efficient method for creating deep, stable foundations. By following the steps outlined in this guide, you can ensure that your pile drilling project proceeds smoothly and safely. Embrace the power and precision of the hammer grab to enhance the quality and efficiency of your construction projects.