A Hydraulic Breaker, also known as a percussion hammer, is a heavy mechanical device used to demolish concrete, asphalt, or stone materials. Hydraulic breakers are commonly seen in road construction and are preferred due to their high performance.
This article gathers information about the best use cases, how they work, and how they are operated. Let’s take a look at the details!
What are the General Characteristics of a Hydraulic Breaker?
In preparation for construction activities, there are several phases of work, including demolition, site preparation, road surface excavation, and public works. To create a modern cityscape, it is sometimes necessary to demolish neighborhoods, often break up sidewalks when opening utility trenches, extend and maintain the network, and remove obstacles in the way of an excavator. Manual demolition hammers that used compressed air for demolition work no longer met growing economic and technical demands.
These tools were sometimes very noisy, required a lot of physical effort from the workers, and we’re far behind other technologies in the chain. Therefore, it has become necessary to develop the range of working tools for hydraulic excavators in a direction aimed at specialized tasks.
Innovation was triggered by a combination of factors:
Some of the assemblies developed are suitable to replace special machines, others decrease the need for manual labor or increase productivity. Assemblies that replace specialized machinery include pile driving equipment, plow lowering and pulling devices, deep compaction assemblies.
In the beginning, the pneumatic demolition hammer was mounted on the excavator, which was later replaced by the hydraulic hammer, which uses the power system of the basic machine.
In the use of Hydraulic Breakers, the following broad areas of application have been outlined, differing in the nature of the work:
What are the advantages of a Hydraulic Breaker over Pneumatic Hammers?
A common feature is that the beater is raised to the home position by the oil supplied by the hydraulic supply of the base machine. In the impact phase, the downward acceleration of the hammer may be provided by mechanical transmission, a spring unit, a pneumatic spring, or a pressurized fluid in addition to the force of gravity. On this basis, hammers are classified into hydromechanical, hydropneumatic, and purely hydraulic hammers.
The hydraulic system of the hammer always includes a hydraulic accumulator, which ensures the correct conditions of movement of the piston or hammer and receives the pressure pulses from the hydraulic system. The movement of the hammer mechanism is controlled either externally via a control spool or internally via a control element integrated into the control spool.
How Does a Hydraulic Breaker Work?
The piston is normally set at the bottom dead center while the mandrel moves freely. The high-pressure oil acting on the lower working surface of the piston head raises the striking piston, which moves upward until it closes the outlet gap in the upper position.
The high-pressure oil in the piston head compresses the energy storage (nitrogen gas in the tank). When the exhaust valve opens, the energy stored in the energy converter is released, pushing the percussion piston downwards with great force.
Demolition hammers can be operated with different accessories. The most common is a demolition spike with a tapered end, which can be used for general demolition work. Flat point tools with different cutting edge lengths are an essential accessory for demolition work, but also for rock cutting and cutting tasks.
A rarely used but typical tool is the blunt crushing tools, which are mainly used for crushing high-strength, brittle materials. Depending on the technological purpose of the tools, they are manufactured with different shaft lengths.
From the hammer’s mode of action, it follows that it is also suitable for compaction and screed-hammering tasks if the tool is properly trained. The working tools are usually made of wear-resistant alloyed steel (manganese and tungsten alloys) or, more rarely, with a carbide insert.
The Moil (conical tool):
How to Select Hydraulic Breaker for Excavator?
The ideal hammer is selected individually for each machine and project. It is necessary to know the weight of the attachment so that the hammer is not undersized, but also so that the loader does not tip out of its equilibrium point in the final position of the boom.
Another important parameter is the hydraulic oil pressure and flow rate per minute: if the oil supply is low, the impact value is not correct or the piston does not start up; if the values are high, immediate damage is also possible.
To determine the most appropriate device for the job, experts conduct thorough calculations based on multiple factors, including the materials to be demolished and the characteristics of the terrain.
Hydraulic breakers brought power, speed, and reliability to the construction industry, and we’re looking forward to seeing the next highly innovative step.