Breaker (hydraulic)
The hydraulic hammer or demolition hammer is a backhoe - attachment to the destruction of components such as stone and concrete or rock, similar to a pneumatic hammer. Unlike some combi cutters, a hydraulic hammer material just break and not cut as reinforcements.
Structure, functioning and indicators
A hydraulic hammer consists of percussion, housing and - as a Tool - Chisel.
The impact mechanism converts from the carrier ( digger ) via high-pressure hoses in the form of hydraulic oil pressure and flow work done in kinetic energy and transfers it to the bit. For this purpose (for example, a nitrogen storage with membrane ) constructed by means of the oil pressure in a memory, which then abruptly releases its contents to the underlying percussion piston and so this set in motion. The per single impact energy transmitted is called the impact energy, the number of single strokes per unit time is called the beat number.
The chisel conducts when the percussion piston impinges on him, its energy into the material to be broken, a, being used depending on the properties pointed, flat, or butt chisels. The chisel is guided by the tool bushing; Chock blocks prevent complete slipping of the bit.
The housing comes in particular to the role of noise and vibration insulation. It is usually closed to and executed damped. Its characteristic, bottom tapered shape derives from the different space requirements of the above- arranged percussion mechanism and the lower disposed chisel socket with the holders ago.
In addition to the impact energy and impact rate especially the net mass and the design height (with or without chisel ) Other key indicators.
To move the hydraulic hammer to press with the necessary force to the material to be broken and to be supplied with hydraulic oil, it is (for example excavators ) mounted on a suitable support device whose size largely depends on the net mass of the hammer.
In order not to damage the retaining wedges and the tool bushing, the hammer may possible not empty, ie without background, are operated. Relevant operating parameters during the operation are the hydraulic pressure and the oil flow in the hydraulic pump on the support device, further, the oil temperature and the back pressure of the reflux oil passage.
For example, you require Montabert BRH 501 of the 1980s with good 1 t mass in about 80 bar pressure at an oil flow of 110-140 ℓ · min -1. From about 1600 J single impact energy were obtained at a maximum of 400 beats per minute. A similar hydraulic hammer nowadays, such as the LST XB 1100 iS, requires 85-130 ℓ · min - 1, but at up to 140 bar, resulting in an impact energy by 2000 J at up to 1060 strokes per minute. Devices of this size are mounted on carrier devices from 12-22 tonnes deadweight.
Large Hydraulic hammers are used mainly as a production machine for direct extraction in quarries. Medium and small hydraulic hammers, however, primarily for secondary crushing, or demolition of buildings, foundations, ditch and road.
Development
The first hydraulic hammer HM 400 was founded in 1967 by Krupp (now Atlas Copco ) developed in food and was probably the first machine- guided demolition tool. It was based on a 1963 patent granted by a hydraulic percussion. However, this first system was in need of improvement. Fully accepted the concept of hydraulic hammer was therefore not until 1969 Montabert (now Ingersoll-Rand ) BRH was put on the market. The BRH 501 is still one of the most widely used hydraulic hammers.