When you watch a hydraulic breaker work, it seems so easy that you may think it is a very simple device. However, the safe use of hydraulic break requires a great deal of knowledge and expertise. There are many details to watch out for during operation so as to protect your hammer from damages. Listed below are just a few of them.
The hydraulic hammer requires 5 to 20 minutes of operation as a warm-up period. Internal parts of the hydraulic breaker are susceptible to damages if proper break-in procedures are not applied in cold weather.
Avoid continuous impact on the same area for more than one minute. Change the place to be hammered frequently. Continuous hammering at the same place results in a rapid increase in oil temperature, and causes both the tool bushing and the tool to wear out rapidly.
Do no use the hammer to move very large rocks or boulders that are uneasy to clear. Hammer operators are prohibited from using the tool end or the side of the hammer bracket to push rocks. In that case, the hydraulic oil pressure needed to drive the hammer is delivered from the two booms of the excavator or the loader. Any sway or slide is very likely to cause damages to booms. There is also a possibility that the hammer bolts rupture, the bracket breaks, or the tool is damaged or scratched. Please note that do not drive the excavator around when the hammer tool is accidentally inserted into the rocks.
Piston surface scratch, breakage, snapped piston, or indentations or cracks on the piston impact area,
I. Causes for Piston Surface Scratches
1. Poor surface hardness
2. Foreign particles mixed with hydraulic oil
3. Too much clearance between the tool and the tool bushings
4. The breaker tool axis deviates from the vertical line. When the piston strikes the top of the oblique tool, it receives an oblique counteracting force which can be decomposed into the vertical and horizontal components: axial stress and radial stress. The radial stress pushes the piston to its side, thereby forcing it to come into contact with the cylinder. Friction between the piston and the oil film on the cylinder surface may finally dry up the lubricating oil. This is when dry friction between the piston and cylinder occurs, which inflicts scratches on the piston surface.
II. Causes for Snapped Piston
Improper forging or heat treating operations leave fatigue cracks on the piston. Under the varying stress or side forces produced during hammering, the cracked would eventually break.
III. Causes for Indentations or Cracks on Piston Impact Surface
1. The poor quality of carburized low-alloy steel is often the root cause of piston surface indentations and cracks. Surveys find that piston impact surface indentations and cracks account of most piston failures.
2. The piston impact area and the tool's pressure-affected area should have proper hardness to withstand continuous blows. Decades of hands-on experience, coupled with the technical exchange with world-renowned piston suppliers, tell us that the two contacting surfaces should have appropriate hardness as well as hardness differential.
What if hoses vibrate excessively?
Breaker operators should firstly check if the excessive vibration comes from the high and low pressure hoses. If it does, stop operation immediately and further check oil leakage at the hose plug. Tighten the plug if the hose leaks oil.
Visually check if there is a surplus of the tool when the breaker is lifted. If there is no surplus, it must have been the case that the tool gets stuck in the front head. That situation calls for an instant disassembly, repair, or replacement.
How to avoid blank hammering?
Blank hammering occurs when the impact force is applied to the rock surface at the incorrect angle or the tool is used as a lever.
Stop hammering as soon as rocks are broken. Continuous blank hammering will not only loosen or break bolts, but also affects adversely the excavator or the loader. When this occurs, the hammer usually creates very strange noises. Therefore, operators should strain their ears during operation, listening to any creepy sounds.
1. Inspect for loose high or low pressure hose each startup. For caution's sake, check for oil leakage from time to time to avoid the oil hose coming off caused by excessive hose vibration.
2. The tool must always be pressed firmly against the material to be broken. The correct strike position should be a 90° angle to the work surface. Stop striking as soon as the rocks are broken. Continued hammer operation after the material is broken will not only loosen breaker bolts or damage the breaker's front head, but it also affect adversely the base machine.
3. Avoid too much play between the tool and the bushings to prevent tool or bolt breakage. Do not allow the breaker to free fall or drop onto hard rocks, which will apply excessive force to the breaker or the base machine, causing damage to many parts of the breaker and the base machine.
4. Do not operate the breaker in water and mud. The breaker components should not be submerged in water or mud except the tool. The piston and similar parts may gather dust and become damaged at an early stage.
5. Use a gradual approach to break up ultra-hard materials. Start at the edge of large pieces and then work in towards the center. Do not operate the hammer tool long on the same spot for more than 1 minute in order to prevent the tool or hydraulic oil for overheating.
6. Avoid moving rocks with the side of the breaker bracket. Most loaders or excavators to which the breaker is attached are lightweight models that are unsuitable for heavy-duty jobs. Using the breaker bracket to move rocks across the ground is likely to cause damage to the hammer, or in extreme cases, lead to boom breakage or the tipping over of base machines.
7. Do not hammer with the base machine cylinder fully extended or extracted. Or else, the impacting vibration would be transferred to the cylinder or even to the base machine.