Is it safe to use a hydraulic jack?

Since entering Chinese market for more than 10 years, products of Wincoo Engineering Co.,ltd has been sold in nearly thirty provinces, cities and autonomous regions in China, and some overseas markets. The company has production line of advanced technology; meanwhile, Wincoo Engineering Co.,ltd designs, develops and processes products for famous domestic installation companies. With professional team, strict management and excellent equipment, the company strives to create the brand of "WINCOO", hydraulic hoist and series supporting products. As an expert of hydraulic hoist, WINCOO with charm of high technology is keen, innovative and forging ahead to establish design language of the company. In an all-inclusive and absorbing and open-minded manner, the hydraulic hoist and hydraulic pump station are perfectly combined to form hydraulic lifting equipment (hydraulic jack). As the founder and disseminator of hydraulic hoist, WINCOO has been building the inverted hydraulic jack and production technology of installation engineering for a long time.We are going to explain how to use the hydraulic jack safely.

●Safe operation code of hydraulic jack

●Precautions for the use of hydraulic jack

●How to repair and maintain hydraulic roof in daily use

Safe operation code of hydraulic jack

1. Hydraulic lifting equipment must be operated by specialized operators;

2. Ground wire must be installed for hydraulic pump station;

3. Check whether motor is rotating in pump indicated direction after startup; motor for this equipment is step-down startup with six second interval. Supply oil for jack after full start of the motor; exhaust air in system via exhaust valve before lifting;

4. Rated pressure for hydraulic system is 25Mpa and pressure indication of pump station pressure gauge cannot exceed 26Mpa;

5. Check clamp block of upper and lower clamps for slip during jack lifting. If block teeth are filled with foreign matters, clean on time and clean the taper sleeve outside block. Grease the taper surface to reduce sliding friction between taper surface and block arc; if teeth shaped surface is severely worn more than 0.4mm, replace block on time. Remove upper and lower clamps and clean after each project. Check wear condition and replace when necessary;

6. Check whether exhaust valve is closed before lifting;

7. Increase pressure slowly during adjustment;

8. System pressure can be at 28Mpa for a short time. Avoid long-term operation for damaging the system;

9. Do not crash high pressure oil pipe with hard objects. Avoid welding slag scorching. Replace high pressure rubber pipe for loss on time;

10. Release the pressure in system via exhaust valve when replacing hydraulic components;

11. Lift jack for a few millimeters when loosening clamp. Unload lower clamp and loosen it;

12. Loosen all lower clamps for butt joint and check; if looseness is inadequate, do not descend jack for opposite joint to avoid lower clamp damage;

13. Adjust pressure precisely when jack is ascending or descending in place. Do not put solenoid valve at neutral position to avoid instantaneous overvoltage;

14. Long-term overload operation is prohibited;

Precautions for the use of hydraulic jack

1. Hydraulic oil level in oil tank should be regularly maintained to normal level. Due to large capacity chamber of piping and hydraulic cylinder, it is mostly required to fill adequate hydraulic oil. After startup, hydraulic oil enters pipeline and cylinder, oil level decreases and filter even shows above oil level. Replenish hydraulic oil once again. It’s inevitable that hydraulic oil has loss during use, therefore, observe oil level regularly and replenish on time to maintain it at the middle position of level meter;

2. Hydraulic oil shall be kept clean always. Use oil filter vehicle when filling hydraulic oil with filtration precision below 30υm;

3. Replacing cycle for hydraulic coil is one year for normal operation;

4. Discharge all residual oil in tank when replacing hydraulic oil and refill after cleaning the tank. Filtration precision of new oil shall not be lower than precision of the system. Oil amount in tank shall be maintained within fixed level range;

5. Oil temperature shall be appropriate, not more than 60℃. Check for abnormal oil temperature rise. Start hydraulic pump and operate as required after oil temperature reaches 15 ℃ during winter;

6. Pay attention to the following for initial startup of hydraulic pump:

7. 1)     Hydraulic oil level in the tank shall be at the full position of vernier;

   2)     Check rotation direction of motor and it shall be clockwise seen from motor tail (arrow direction). If the direction id reversed, stop immediately and regain operation after handling;

   3)     Step up after 10 minutes’ idle operation of pump station;

8. Pay attention to check return oil filter. Replace cartridge for damage on time;

9. Before starting and stopping hydraulic pump, unload the overflow valve;

10. Spares for wear parts (seal ring, clamp block, etc.) shall be available at all times for timely replacement;

11. Set pressure of overflow valve cannot exceed maximum pressure of hydraulic system;

12. Check and maintain the jack before operation to ensure there is no oil leakage, clamp and the whole machine is in good condition;

13. When inserting lifting rod, the jack shall be loosened (loosening nuts at upper and lower clamps are screwed upward in place). Note that lifting rod and jack shall be almost concentric. Reset upper and lower clamps for normal operation and make the jack in operating state;

14. Prevent mud and sand from entering hydraulic rubber pipes during connection to avoid damaging hydraulic system and the jack;

15. Overpressure (overload) is prohibited during operation;

16. Lifting height shall exceed 20-30mm of coaming height and make jack piston at middle position for butt weld;

17. Make the jack at lifting state when descending the rod and oil pressure cannot be higher than that during lifting, that is to adjust oil pressure below that during normal lifting and then loosen lower clamp. After the jack is back stroke and lifted steel plate falls on newly surrounded plates, the jack bears no load. Loosen upper clamp and lifting rod descends;

18. According to actual ambient temperature, it is decided to use N46 anti-wear hydraulic oil for the system and mix of other grades is prohibited;

19. Clean and maintain the jack on time after one project, especially attachment at clamp block teeth. Replace for severe teeth wear and repair the replaced jack.

How to repair and maintain hydraulic jack in daily use

A.Routine inspection items and contents

Time for inspection	Items	Contents
Monitor operating status during equipment   operation	Pressure	System pressure is stable and within   specified scope.
	Noise and vibration	Normal
	Oil temperature	Within 15-60℃, not more than 60℃
	Voltage	Within 105%-85% of rated voltage
	Oil leakage	For oil leakage of the system
Inspect before startup	Oil level	Whether at red scale of level meter
	Overflow valve	Whether overflow valve is loosened
	Ground wire	Whether ground wire is installed for pump   station

B.Periodical inspection items and contents

Items	Contents
Screw and pipe joints	Regular fastening: once a month
Oil filter and air filter	Regular inspection: once a month
Valve plate of oil tank pipeline	Regular inspection: dismantle, clean and   replace sealing during overhaul
Sealing element	Specify as per working conditions and   temperature, replace once every 3-4 years generally.
Spring	Specify as per working conditions and   element quality. Replace for damage on time.
Hydraulic oil pollution test	Test after 1000 hours’ operation of the   newly replaced hydraulic oil.
	Sample with dedicated container to avoid   pollution.
	Sample the operating heated oil instead   of static oil.
	Sample 300-500ml each time.
	Test oil plants test report and   incorporate the result into equipment record.
Pressure gauge	Specify inspection cycle as per equipment   usage.
High pressure rubber pipe	Specify replacement cycle as per working   conditions.
Hydraulic components	Specify performance inspection of pump,   valve, etc. as per working condition.

Hydraulic jacking system as a widely used tank lifting machine, its safety is widely supported and proven.What we said above is more to help you know how to use the hydraulic jack safely and correctly. I hope you found this helpful.