The hydraulic fluid acts as a vehicle transmitting energy from the point of transformation to the point of use of any hydraulic system .
Theoretically, any fluid could be used as a hydraulic fluid, since they all comply with Pascal's laws : "All pressure exerted on a confined liquid is transmitted without loss equally to all points of its mass and acts with equal forces on equal areas."
Elevator oil classification
Following this concept, the variety of fluids to be used would be very wide; however, in practice, the number of fluids used is limited to classifying them by their flammability:
a) Flammable fluids: mineral-based oils b) Non-flammable fluids or fluids that are difficult to ignite: – emulsion of oils in water – water in oil emulsion – polymer solutions in water – water-free synthetic fluids
Objectives of elevator oil
Every hydraulic fluid must meet four main objectives:
Transmit power: As a power transmission medium, the fluid must be able to circulate easily through the circuit with the least pressure loss.
Lubricate and protect: In most hydraulic mechanisms, internal lubrication is provided by the fluid in order to reduce friction between the elements that slide against each other (e.g., vane-ring) on a film of fluid, so that their life is as long as possible. To achieve this, an adequate viscosity must be maintained at the operating temperature, protecting the surfaces from wear, corrosion and rust, while keeping them free of impurities.
Tightness: in many cases the fluid acts as a sealant or gasket within the mechanisms.
Cooling: Internal leaks and internal friction of hydraulic components generate heat; this heat must be distributed either by appropriate devices (heat exchangers) or through storage lines and tanks. The function of the fluid is to transport the generated heat to the points where it will be dissipated to avoid temperature peaks at the generation points.
Apart from these basic functions, the hydraulic fluid is required to have several characteristics with greater or lesser impact, depending on the design and requirements of the manufacturer of the system components, the main ones being viscosity and thermal and chemical stability, among others.
Fluids used in GMV
At GMV we basically work with two types of hydraulic fluids: ecological fluid and mineral fluid, both of which have anti-wear properties, which are important for extending the life of hydraulic equipment.
– Mineral Fluid Petroleum derived base High flash point (over 200ºC), in traditional oils (180ºC) Lower cost ISO VG 46 fluid
– Ecological Fluid Synthetic base 90% biodegradable High flash point (over 250ºC), considered fireproof HEES classified according to ISO 6743-4 regulation
If an oil that is not recommended is used, impurities may form in the fluid, which could affect the operation of the elevator. It may also damage the elevator's motor , brake or pipes . It is crucial to perform proper maintenance and check the oil level and quality frequently.
The problem is not the outside temperature, but the oil temperature. When the oil is at low temperatures it is very thick, and during the first trips of the day it does not circulate well through the valve group shutters. The solution is to put a heating resistor in the oil tank of the hydraulic unit.
I explain my case to see if you can give me some explanation:
Nine months ago the central unit got wet from above and a valve had to be replaced. At first glance it did not seem that water had entered the central unit's tank because no strange colour could be seen and the lift was working properly. A few days ago the power plant broke down, and when I opened it the oil looked curdled and foamy.
I ask: Is it possible that water got in 9 months ago and it worked normally and now that it has mixed more with the oil it has caused it to rot and the engine to cross?
You see, I have a hydraulic lift that when the load is put on the cylinder is compressed a lot it seems like it rocks and when it changes speed I don't even want to tell you. I have bled the piston several times but nothing, I don't know if the problem is the oil, but the truth is that the central unit is very hot, so much so that the oil thermistor which is bridged jumps and I don't know if this temperature modifies the behavior of the oil and the lift. What is clear is that the oil is heated by the engine since it doesn't have any type of resistance in the tank and the engine doesn't start enough times to reach this temperature, the central unit is GMV and the block is a 3010. What do you think could be happening? THANKS IN ADVANCE.
The situation you describe may be due to the equipment working beyond the installation's dimensions, which causes the oil to heat up excessively and cause the elevator to malfunction.
If the equipment has been designed, for example, to make 30 starts/hour (about 60 trips in one hour) but is working above these forecasts, the temperature problems may be because not all the heat generated by the installation is dissipated. It will also depend on the type of installation (indoor, outdoor or panoramic elevator) and the location of the central (properly ventilated machine room or in an area where there is no ventilation), which are factors that determine the working conditions of the equipment.
When the equipment has temperature problems, speed changes become more acute because depending on the type of fluid being used, it may be more or less affected by temperature changes.
We recommend that you perform the following checks:
1. Check that the valve group's heating resistor (located inside the valve group) is working correctly or that it is not directly connected to voltage, which would cause it to be constantly working, producing an increase in temperature. 2. Check the correct ventilation of the work area of the plant (machine room, cabinet, etc.) to verify that the heat generated in the tank can be properly dissipated. 3. Check the sizing of the installation: that is, that it is working correctly based on the calculation forecasts. If the elevator is working above the forecasts, it may be necessary to use a refrigerator (more information in the article How can we improve the performance of an elevator?).
In order to help you resolve any incident, we would need to correctly verify all the data in order to carry out a more personalized follow-up. If you wish, you can contact our SAT Department (technical assistance service) through 902 345 234 , +34 937 745 455 or sat@es.gmvgrupo.com .
We hope you can resolve the issue! If you have any further questions, please do not hesitate to contact us.
I have a small problem with a hydraulic elevator. After a while, while at floor level, it drops about 3 cm below the level, preventing the door from opening... from what I was seeing in previous comments, would I have to check the pressure? Do I have some kind of leak or what other solution can you give me? Thank you very much for everything
Hello! Thank you for your enquiry. We cannot know what type of oil the lift company used in your installation, so it is best to contact them to find out this information. We, as manufacturers, recommend the ecological fluid or the HV-46 mineral fluid to obtain the best performance from the lift.
I wanted to know what hydraulic fluid a MIC lifter uses. It has hydraulic fluid but I wanted to refill it and I don't know if it can be mixed with another hydraulic fluid and I don't know which one to use.
Hello, I wanted to know what is the useful life of the hydraulic oils used in the elevators. The question is because the company that performs maintenance is informing us that it is time to change the oil and the elevators have been operating for 16 years and their use is very low because the building is not always fully occupied, that is, we live in 50% of it.
Good morning, The time to change the oil in a hydraulic lift depends on the use and the temperature at which it works. After 16 years it is quite likely that it will need to be changed, however the definitive test would be to perform an analysis of the oil and check if it has lost properties. This would have to be assessed on a case-by-case basis, since the cost of this analysis could be higher than that of the oil itself.
Hello, I have a hydraulic elevator that works well, but 30 cm before reaching the floor it slows down and takes forever to get there. It is outdoors. What would be the probable cause of this failure? Could it be a clogged valve or contaminated oil?
Hi Lucas, in response to your question, based on what you have indicated, it is most likely that the slow speed will have to be increased. If it is a 3010 valve block, loosening screw #2 increases the slow speed. If it is an NGV valve block, with the console, the value of menus 6.4 and 7.4 would have to be increased.
If the oil is more than 10 years old, it can also influence this situation and should be changed.
Good afternoon. I have a GMV MI-100/8 hydraulic unit. I would like to know which oil you recommend, how to change it to replace the oil, the recommended temperature to keep the oil in good working condition, and the approximate amount needed (3 levels). Thank you very much!
Hello Juan, we as manufacturers recommend using HV 46 type oil. To help you calculate the amount of oil needed for the installation you indicate, we would need to know the diameter of the piston and the existing tank.
Hello, I am writing to you from Arequipa, Peru. I live in a 5-story building with 12 apartments and we have a hydraulic elevator with a capacity for 6 people. We are repairing the motor that is submerged in the oil tank, after the three-phase motor burned out due to a fault in the city's power plant when a phase failed. The motor worked with two and fused, having also overheated the oil to the point of producing smoke, so it is necessary to change it. Please tell me the name and type of oil that I should buy and if you sell it here. Thank you Miguel Tejada
Good morning. I have a hydraulic lift for people with reduced mobility. When the warmer months arrive, in fact it already does so, it does not go down to ground level, it stays a couple of centimetres elevated, which makes it difficult for the person who uses it to get in. How could this be fixed?
Good evening, I have a GMV 3010 1.1'4 hydraulic block in a car lift, it goes up with its gear changes but does not go down. The valve filters were cleaned, no loose screws were checked, the solenoid valve tension is fine, what could it be or what should I check?
Good morning, please could you help me? The equipment lowers very slowly when it is on the ground. I mean, there is some leak in the hydraulic block that I would have to check. It is a GMV 3010 1.1'4 equipment.
34 comments
Why does our elevator stop when the outside temperature drops below 5 degrees?
Hello Alonso,
The problem is not the outside temperature, but the oil temperature. When the oil is at low temperatures it is very thick, and during the first trips of the day it does not circulate well through the valve group shutters. The solution is to put a heating resistor in the oil tank of the hydraulic unit.
Greetings,
I explain my case to see if you can give me some explanation:
Nine months ago the central unit got wet from above and a valve had to be replaced. At first glance it did not seem that water had entered the central unit's tank because no strange colour could be seen and the lift was working properly.
A few days ago the power plant broke down, and when I opened it the oil looked curdled and foamy.
I ask: Is it possible that water got in 9 months ago and it worked normally and now that it has mixed more with the oil it has caused it to rot and the engine to cross?
Or what other explanation could there be?
Thanks and Greetings.
Good night MAR:
You see, I have a hydraulic lift that when the load is put on the cylinder is compressed a lot it seems like it rocks and when it changes speed I don't even want to tell you. I have bled the piston several times but nothing, I don't know if the problem is the oil, but the truth is that the central unit is very hot, so much so that the oil thermistor which is bridged jumps and I don't know if this temperature modifies the behavior of the oil and the lift. What is clear is that the oil is heated by the engine since it doesn't have any type of resistance in the tank and the engine doesn't start enough times to reach this temperature, the central unit is GMV and the block is a 3010. What do you think could be happening? THANKS IN ADVANCE.
Good afternoon Jose Luis,
The situation you describe may be due to the equipment working beyond the installation's dimensions, which causes the oil to heat up excessively and cause the elevator to malfunction.
If the equipment has been designed, for example, to make 30 starts/hour (about 60 trips in one hour) but is working above these forecasts, the temperature problems may be because not all the heat generated by the installation is dissipated. It will also depend on the type of installation (indoor, outdoor or panoramic elevator) and the location of the central (properly ventilated machine room or in an area where there is no ventilation), which are factors that determine the working conditions of the equipment.
When the equipment has temperature problems, speed changes become more acute because depending on the type of fluid being used, it may be more or less affected by temperature changes.
We recommend that you perform the following checks:
1. Check that the valve group's heating resistor (located inside the valve group) is working correctly or that it is not directly connected to voltage, which would cause it to be constantly working, producing an increase in temperature.
2. Check the correct ventilation of the work area of the plant (machine room, cabinet, etc.) to verify that the heat generated in the tank can be properly dissipated.
3. Check the sizing of the installation: that is, that it is working correctly based on the calculation forecasts. If the elevator is working above the forecasts, it may be necessary to use a refrigerator (more information in the article How can we improve the performance of an elevator?).
In order to help you resolve any incident, we would need to correctly verify all the data in order to carry out a more personalized follow-up. If you wish, you can contact our SAT Department (technical assistance service) through 902 345 234 , +34 937 745 455 or sat@es.gmvgrupo.com .
We hope you can resolve the issue! If you have any further questions, please do not hesitate to contact us.
Greetings,
I have a small problem with a hydraulic elevator. After a while, while at floor level, it drops about 3 cm below the level, preventing the door from opening... from what I was seeing in previous comments, would I have to check the pressure? Do I have some kind of leak or what other solution can you give me?
Thank you very much for everything
Hello, I have a hydraulic lift and I want to know what oil it takes.
Hello!
Thank you for your enquiry. We cannot know what type of oil the lift company used in your installation, so it is best to contact them to find out this information. We, as manufacturers, recommend the ecological fluid or the HV-46 mineral fluid to obtain the best performance from the lift.
I wanted to know what hydraulic fluid a MIC lifter uses. It has hydraulic fluid but I wanted to refill it and I don't know if it can be mixed with another hydraulic fluid and I don't know which one to use.
Hello, I wanted to know what is the useful life of the hydraulic oils used in the elevators. The question is because the company that performs maintenance is informing us that it is time to change the oil and the elevators have been operating for 16 years and their use is very low because the building is not always fully occupied, that is, we live in 50% of it.
Good morning,
The time to change the oil in a hydraulic lift depends on the use and the temperature at which it works.
After 16 years it is quite likely that it will need to be changed, however the definitive test would be to perform an analysis of the oil and check if it has lost properties. This would have to be assessed on a case-by-case basis, since the cost of this analysis could be higher than that of the oil itself.
Hello, I have a hydraulic elevator that works well, but 30 cm before reaching the floor it slows down and takes forever to get there. It is outdoors. What would be the probable cause of this failure? Could it be a clogged valve or contaminated oil?
Hi Lucas, in response to your question, based on what you have indicated, it is most likely that the slow speed will have to be increased.
If it is a 3010 valve block, loosening screw #2 increases the slow speed.
If it is an NGV valve block, with the console, the value of menus 6.4 and 7.4 would have to be increased.
If the oil is more than 10 years old, it can also influence this situation and should be changed.
Greetings
Good afternoon. I have a GMV MI-100/8 hydraulic unit. I would like to know which oil you recommend, how to change it to replace the oil, the recommended temperature to keep the oil in good working condition, and the approximate amount needed (3 levels). Thank you very much!
Hello Juan, we as manufacturers recommend using HV 46 type oil. To help you calculate the amount of oil needed for the installation you indicate, we would need to know the diameter of the piston and the existing tank.
The information in the article has been very helpful to us with our boat heat exchangers. Thank you very much.
Hello, I am writing to you from Arequipa, Peru. I live in a 5-story building with 12 apartments and we have a hydraulic elevator with a capacity for 6 people. We are repairing the motor that is submerged in the oil tank, after the three-phase motor burned out due to a fault in the city's power plant when a phase failed. The motor worked with two and fused, having also overheated the oil to the point of producing smoke, so it is necessary to change it. Please tell me the name and type of oil that I should buy and if you sell it here.
Thank you
Miguel Tejada
Good morning.
I have a hydraulic lift for people with reduced mobility. When the warmer months arrive, in fact it already does so, it does not go down to ground level, it stays a couple of centimetres elevated, which makes it difficult for the person who uses it to get in. How could this be fixed?
Thank you so much
Good evening, I have a GMV 3010 1.1'4 hydraulic block in a car lift, it goes up with its gear changes but does not go down. The valve filters were cleaned, no loose screws were checked, the solenoid valve tension is fine, what could it be or what should I check?
Good morning, please could you help me? The equipment lowers very slowly when it is on the ground. I mean, there is some leak in the hydraulic block that I would have to check. It is a GMV 3010 1.1'4 equipment.