The pile driving hammer is one of the important equipment in pile foundation construction. It is widely used in the foundation construction of industrial and civil buildings, ports, docks, bridges, etc. It has the characteristics of high piling efficiency, low cost, easy damage to the pile head, and small pile deformation. Etc. And with the rapid development of the modern construction industry, pile foundations have gradually developed from wooden piles to reinforced concrete piles or steel piles. The types of piles can generally be divided into two categories: prefabricated piles and cast-in-place piles. Precast piles are mainly driven into the soil by hammering. Its construction machinery has also evolved from falling hammers, steam hammers and diesel hammers to hydraulic vibration piling hammers.
Current piling hammers can be divided into two major categories. One type uses a rotary vibrator, which generates vibration through the rotation of an eccentric shaft (an axis whose center of gravity does not coincide with the center of rotation or a shaft with an eccentric block); the other type uses a reciprocating vibrator, usually Hydraulic oil drives the piston to reciprocate in the cylinder, causing vibration. If a rotary vibrator is used, if the driving device of the vibrator is an electric motor, it is an electric piling hammer; if the driving device of the vibrator is a hydraulic motor, it is a hydraulic piling hammer. This kind of hydraulic piling hammer is increasingly used in our country, including both imported and domestic ones. Several or dozens of pile driving hammers using rotary exciters can be connected to vibrate synchronously for the construction of very large prefabricated piles.
The working principle of the hydraulic vibration piling hammer: the hydraulic motor is made to perform mechanical rotation through the hydraulic power source, so that each pair of eccentric wheels in the vibration box rotates in the opposite direction at the same angular speed; the centrifugal force generated by the rotation of the two eccentric wheels is The components in the direction of the line connecting the center of the rotating shaft will cancel each other out at the same time, while the components in the vertical direction of the line connecting the center of the rotating shaft will superpose each other and eventually form the pile (pipe) excitation force.
Comparison between electric piling hammer and hydraulic vibration piling hammer
Limitations of electric piling hammer applications:
1. The equipment is larger than the equipment with the same exciting force, and the size and mass of the electric hammer are larger. Moreover, the increase in mass also affects the effective utilization of the exciting force.
2. The vibration damping effect of the spring is poor, resulting in a large energy loss in the upward transmission of the excitation force along the steel rope, about 15% to 25% of the total energy, and may cause damage to the supporting lifting equipment.
3. The low frequency (medium and low frequency piling hammer) cannot effectively liquefy some difficult and hard strata, especially the sand layer, resulting in difficulty in pile sinking.
4. Do not work underwater. Because it is driven by a motor, its waterproof performance is relatively poor. Do not engage in pile driving operations underwater.
Advantages of hydraulic vibration piling hammer:
1. The frequency is adjustable, and low-frequency and high-frequency models can be easily selected. Since the excitation force is proportional to the square of the frequency, the excitation forces of hydraulic hammers and electric hammers of the same size are very different.
2. The use of rubber vibration damping can maximize the excitation force for pile driving and pulling operations. Especially during pile pulling operations, it can provide more effective pulling force.
3. It can be operated both above and below water without any special treatment.
With the further expansion of the scale of infrastructure construction in our country, especially the successive start of some large-scale foundation projects, a broad space has been provided for the hydraulic vibration piling hammer, making it an indispensable key equipment. For example, there are increasingly larger deep foundation pit projects, large-scale barrel pile construction and large-scale steel casing construction projects, soft foundation and rotary drilling rig construction projects, high-speed railway and basic roadbed construction projects, sea reclamation and reclamation projects and treatment projects. Sand pile construction, as well as a wider range of municipal construction projects, pipeline construction, sewage interception treatment and supporting earth retaining projects, are all inseparable from hydraulic vibration piling hammers.
Yantai Juxiang Construction Machinery Co., Ltd. is one of the largest excavator attachment design and manufacturing companies in China. Juxiang Machinery has 15 years of experience in engineering machinery design, production and processing, more than 50 R&D engineers, and produces more than 2,000 sets of piling equipment annually. Juxiang Machinery has maintained close cooperation with domestic first-tier OEMs such as SANY, Xugong, and Liugong all year round. The piling equipment produced by Juxiang Machinery has excellent craftsmanship and superb technology. The products have benefited 18 countries, sold well all over the world, and received unanimous praise. Juxiang has the outstanding ability to provide customers with systematic and complete sets of engineering equipment and solutions, and is a reliable engineering equipment solution service provider.
Post time: Dec-08-2023