Proper installation is critical to ensuring the stable operation, precise positioning, and long service life of the dual-input shaft screw jack. As a versatile mechanical linear actuator with two coaxial input shafts, its installation requires strict compliance with technical specifications to avoid structural damage, transmission failure, or safety hazards. This article details the comprehensive installation specifications for dual-input shaft screw jacks, including pre-installation preparation, step-by-step installation procedures, key technical requirements, and post-installation inspection, providing a professional guide for industrial installation personnel and ensuring the jack performs optimally in various application scenarios.
The dual-input shaft screw jack's unique dual-shaft design requires special attention to the alignment of input shafts, load distribution, and mounting stability during installation-unlike single-input jacks, improper installation of either input shaft can affect the overall transmission efficiency and safety. Adhering to the following specifications will minimize installation errors, reduce later maintenance costs, and ensure the jack operates reliably under rated load and working conditions.
1. Pre-Installation Preparation
Adequate preparation before installation is the foundation for smooth installation and stable operation. All steps must be completed carefully to avoid delays or potential risks during the installation process.
1.1 Check the Jack and Accessories
Inspect the dual-input shaft screw jack for any damage during transportation, such as housing deformation, input shaft bending, screw scratches, or gearbox oil leakage. If any damage is found, stop installation immediately and contact the supplier for repair or replacement.
Verify that all accessories (mounting bolts, washers, couplings, handwheels, motors, etc.) are complete and intact, and match the jack's specifications. Ensure that the input shafts, couplings, and connecting components are free of burrs, rust, or foreign objects that may affect transmission.
Check the gearbox lubrication: the jack is pre-filled with long-acting lubricating grease at the factory; confirm the oil level through the oil sight glass (if equipped) and ensure there is no oil leakage. If the lubrication is insufficient or contaminated, add or replace the specified lubricating grease before installation.
1.2 Prepare the Installation Site and Tools
Select a flat, stable installation surface that can bear the jack's rated load and the weight of the connected equipment. The installation surface must be free of unevenness, cracks, or loose debris to ensure the jack is mounted stably without vibration during operation.
Clear the installation area of obstacles, especially around the two input shafts, to ensure sufficient operation space for connecting motors, handwheels, or transmission shafts, and to facilitate later maintenance and operation.
Prepare the required tools: torque wrench, level, measuring tape, caliper, screwdriver, wrench, and lifting equipment (if the jack is heavy). Ensure all tools are calibrated and in good condition to guarantee installation accuracy.
1.3 Confirm Installation Orientation and Load Direction
Determine the installation orientation (upright, inverted, or horizontal) according to the application requirements, and confirm the load direction (tension or compression) to ensure the jack's screw and bearing system can withstand the load correctly. Mark the installation position and the connection points of the input shafts to avoid misalignment during installation.
2. Step-by-Step Installation Procedures
Follow the below steps in sequence to ensure correct installation of the dual-input shaft screw jack. Do not skip any steps or modify the installation sequence without authorization.
2.1 Mount the Jack to the Installation Base
Place the jack on the pre-marked installation position, adjust the jack to be level using a level (horizontal and vertical deviation ≤0.5mm/m), and ensure the jack's housing is closely attached to the installation base without gaps.
Use the specified mounting bolts to fix the jack to the base. Tighten the bolts evenly with a torque wrench according to the recommended torque (refer to the technical parameters), and use washers to prevent loosening due to vibration during operation. Do not over-tighten the bolts to avoid damaging the jack's housing or the installation base.
2.2 Align and Connect the Input Shafts
The alignment of the two input shafts is critical to the transmission stability of the dual-input shaft screw jack. Improper alignment will cause uneven load on the gears and bearings, leading to increased noise, wear, and even equipment failure.
For motor-driven input: Align the motor output shaft with the jack's input shaft using a coupling. Ensure the coaxiality of the two shafts (coaxiality deviation ≤0.1mm) and the parallelism of the end faces (end face runout ≤0.05mm). Use a caliper or dial indicator to check the alignment, and adjust the motor position if necessary.
For manual handwheel input: Install the handwheel on the other input shaft, ensuring the connection is tight and there is no looseness. Rotate the handwheel manually to check if the input shaft rotates smoothly without jamming or abnormal noise.
If both input shafts are connected to motors or transmission components, ensure the two input shafts are coaxial and the transmission directions are consistent. Install a protective cover on the input shafts and couplings to prevent accidental injury during operation.
2.3 Connect the Load to the Screw
Connect the load to the threaded head of the lifting screw using appropriate connecting components (such as flanges, brackets, or pins). Ensure the load is centered on the screw's axis to avoid eccentric load, which may cause bending of the screw or damage to the bearing system.
Check the connection between the load and the screw to ensure it is tight and reliable. For heavy loads, add anti-loosening devices (such as lock nuts or split pins) to prevent the load from slipping during operation.
Adjust the position of the screw to the initial working position (middle of the stroke is recommended) to avoid the screw being in the extreme position during the first operation, which may cause overload.
2.4 Install Safety and Auxiliary Components
Install stroke limit switches (if required) at the upper and lower limit positions of the screw to prevent the screw from exceeding the stroke range, which may damage the jack or the load.
For vertical installation, install a safety nut (if equipped) on the screw to provide secondary protection against load drop in case of screw failure.
If the installation environment is dusty, humid, or corrosive, install a protective cover or bellows on the screw to prevent foreign objects from entering the gearbox or damaging the screw surface.
3. Key Installation Technical Requirements
To ensure the jack's performance and safety, the following technical requirements must be strictly followed during installation:
Coaxiality Requirement: The coaxiality deviation between the input shaft and the connected motor/transmission shaft shall not exceed 0.1mm; the coaxiality deviation between the two input shafts of the jack shall not exceed 0.08mm.
Levelness Requirement: The horizontal and vertical levelness of the jack during installation shall not exceed 0.5mm/m to avoid uneven load distribution and transmission interference.
Bolt Torque Requirement: Use the specified torque to tighten the mounting bolts and connecting bolts; over-tightening or under-tightening will affect the installation stability. The recommended torque is based on the bolt size and material, which can be referred to the technical parameters.
Eccentric Load Requirement: The load must be centered on the screw's axis; the eccentric load shall not exceed 10% of the rated load, otherwise, it will reduce the jack's service life and may cause safety hazards.
Lubrication Requirement: Ensure the gearbox is filled with the specified lubricating grease before installation; do not use incompatible lubricants, which will damage the internal gears and bearings.
4. Post-Installation Inspection and Test Run
After completing the installation, a comprehensive inspection and test run must be carried out to confirm that the jack is installed correctly and can operate normally.
4.1 Post-Installation Inspection
Recheck the installation position, levelness, and bolt tightness of the jack to ensure there is no looseness or misalignment.
Check the connection of the input shafts, couplings, and load to ensure they are tight and reliable; check the safety components (limit switches, safety nuts) to ensure they are installed correctly and can work normally.
Inspect the gearbox for oil leakage; if there is oil leakage, check the oil seal and tighten the relevant bolts or replace the oil seal.
4.2 Test Run
Empty Load Test: Operate the jack in empty load mode (manual or motor drive) to run the screw through the full stroke twice. Check if the input shafts rotate smoothly, the screw moves linearly without jamming, and there is no abnormal noise or vibration. Record the operation status.
Light Load Test: Apply 25% of the rated load to the jack, run it through the full stroke twice, and check the transmission stability, load holding performance, and safety components. Ensure the self-locking function is reliable when the jack stops at any position.
Rated Load Test: Apply the rated load to the jack, run it through the full stroke once, and check the transmission efficiency, noise, temperature rise, and load holding performance. The temperature rise of the gearbox shall not exceed 40℃, and the noise shall not exceed 80dB.
If any abnormal phenomenon (such as jamming, abnormal noise, oil leakage, or load sliding) is found during the test run, stop the operation immediately, check the cause, and rectify it before continuing the test run.
5. Installation Precautions and Safety Tips
Installation personnel must be trained and familiar with the structure and installation specifications of the dual-input shaft screw jack; do not operate without authorization.
During installation, use lifting equipment correctly to avoid injury to personnel or damage to the jack due to improper lifting.
Do not modify the jack's structure or installation method without the supplier's permission, which may affect the jack's performance and safety and void the warranty.
After installation, mark the installation date, test run results, and maintenance records for future reference.
Regularly check the installation status of the jack during use, including bolt tightness, input shaft alignment, and lubrication, to ensure long-term stable operation.
Conclusion
The installation of the dual-input shaft screw jack is a systematic process that requires strict compliance with pre-installation preparation, standard installation procedures, and key technical requirements. Proper installation not only ensures the jack's precise positioning, stable transmission, and long service life but also minimizes safety hazards and later maintenance costs. By following the installation specifications detailed in this article, installation personnel can complete the installation correctly and efficiently, enabling the dual-input shaft screw jack to play its optimal performance in various industrial applications, such as multi-point synchronous lifting, heavy-duty positioning, and emergency backup operation.
