Hollow hydraulic jacks are special jacks for prestressing tendons such as steel hinges. The post tension jack needs to be used in conjunction with a high pressure electric oil pump. Anchorage systems for highways, railways, beam manufacturing plants, bridges and tunnels, box beams, foundation pits, slope protection, hydropower, etc.
The prestressed tensioning equipment mainly includes tensioning jacks and electric oil pumps for tensioning (tensioning Oil pump) is used in cooperation to increase the strength of steel strands or steel bars in the anchor to give a prestress value. Post tension jack has many features. The jack not only improves the working efficiency but save costs as well.
Parameters
| Models | Rated Load Capacity (Ton) | Pump Oil Pressure (Mpa) | Stroke (mm) | Body Dimension (mm) |
| Items | (Dia. x Length) | |||
| YGM-650 | 65 | 50 | 200 | Φ170 x 288 |
| YGM-1100 | 110 | 50 | 200 | Φ218 x 330 |
| YGM-1500 | 150 | 50 | 200 | Φ270 x 330 |
| YGM-2000 | 200 | 50 | 200 | Φ320 x 360 |
| YGM-2500 | 250 | 50 | 200 | Φ350 x 360 |
| YGM-3000 | 300 | 50 | 200 | Φ375 x 380 |
| YGM-3500 | 350 | 50 | 200 | Φ415 x 395 |
| YGM-4000 | 400 | 51 | 200 | Φ435 x 395 |
| YGM-4600 | 460 | 51 | 200 | Φ470 x 410 |
| YGM-5000 | 500 | 51 | 200 | Φ495 x 410 |
Post-Tension Jack Application
The power for tensioning and returning is provided by the high-pressure oil of the tensioning oil pump. The hollow hydraulic jack has a compact structure, works stably during tensioning, high oil pressure, and high tension force, and is widely used in prestressed construction projects such as highway bridges, railway bridges, hydropower dams, and high-rise buildings. The accuracy of the tensioning force of the prestressed tensioning jack device will directly affect the engineering quality and production safety.
Therefore, it is very important to calibrate it and issue accurate and reliable test data. The post tension jack is simple to operate, reliable in performance and saves steel strands. It is designed with a safety pressure maintaining device and built-in pressure relief valve to prevent overload to protect the jacks for safe operation. The connection of this device uses high-pressure hoses and threaded joints. It is fast to use and overcomes the shortcomings of traditional oil leaks.
Steps Before Using Hollow Hydraulic Jack
The parameters of the hollow hydraulic jack should be strictly checked before use, and the use of overpressure and overload should be avoided. Check the amount of oil in the pump before tensioning, and run the jack several times to empty the air in the jack and the oil pipe. The post tension jack is mainly used for group anchor overall tension.
- When installing anchors and jacks, for straight prestressed tendons, the action line of the tensile force should coincide with the centerline of the channel during the tensioning process.
- For curved prestressed tendons, the action line of the tensile force should be at the center of the end of the channel The tangents coincide with each other.
When tensioning, the prestressing tendons pass through the middle of the working anchor, the limit plate and the jack. The tensioning sequence of the prestressed tendons shall meet the design requirements.
Post-Tension Jack Features
- This type of hollow hydraulic jack adopts the ring prestressing heat treatment process, which makes the jack not only small in size and light in weight but also high in strength, good in sealing performance, and high in reliability.
- The jack adopts a new type of seal so that the sealing strength of the seals of the cylinder block can be enhanced simultaneously when it is under high pressure.
- The use of special alloy steel cylinder block material in combination with the heat treatment process reduces the expansion ratio of the cylinder block during tensioning, which improves the life and sealing performance of the seal by about 20%.
- Aiming at the problem that the post-tension jack’s return pressure is likely to damage the jack during the tensioning operation, an overpressure protection valve is added to the jack for pressure relief protection.
Precautions For Using Hollow Hydraulic Jack
- If there is a runaway phenomenon during use, first loosen the oil drain screw on the pump body, lift the pump body upright, and hit it downward a few times, then tighten the oil drain screw to continue using.
- When there is a load, do not remove the quick connector to avoid accidents and damage to the parts.
- A hollow hydraulic jack uses oil as the medium, and the maintenance of the oil and the machine must be done well to avoid blockage or oil leakage and affect the use effect.
Hollow Hydraulic Jack For Sale in YG
Hollow Hydraulic Jack for sale produced by YG is of high quality. As one of the reliable jack manufacturers, we get along well with our clients and keep exploring new products to help clients. We insist high quality can win the clients and we just concentrate on the quality of our products and provide proper machines for you. We have a group of engineers and experienced workers and they keep innovating and try to improve the performance of the product. Just contact us for whatever you need and we’ll help you find your choice.
