How to make a hydraulic cylinder for the greenhouse with your own hands? For those who appreciate offline operation

Timely airing of the greenhouse - one of the necessary conditions for healthy plant growth.

And for this it is necessary to periodically open and close the vents, thus controlling the indoor climate.

But not all land owners are able to consistently carry out this procedure.

In this case, the problem can be solved by using automatic opening devices Vents on the basis of the hydraulic cylinder. To manufacture such a device, everyone will be able to independently.

How does a hydraulic cylinder work?

Cylinder is the same hydraulic motorreciprocating.

The device consists of a sealed housing in which a piston with a rod is installed.

Oil, air or other substance, acting under pressure inside the device, causes the piston to move, which drives the rod.

reference: in view of the foregoing, it follows that the operation of the hydraulic cylinder requires the presence of air pressure pumped by a pump.

The hydraulic cylinder used in the greenhouse functions according to the same principle, but its operation does not require the presence of a pump and auxiliary energy.
The laws of physics say that the volume of heated substances increases.Hydraulic cylinder with hermetic housing filled with a certain fluid.

With a low positive temperature, a small pressure inside the device does not affect the stem, allowing it to remain in a fixed position.

Once the temperature risesthe fluid expands, resulting in pressure inside the cylinder increases.

Under pressure, a piston with a rod moves. The rod attached to the greenhouse frame will open the sash when moving, which will provide ventilation inside the greenhouse.

Advantages and disadvantages

The advantages of this design include the following points.:

  • offline operation. The hydraulic cylinder for the greenhouse does not need any intervention in the operation;
  • reliability. The simple principle of action, which is based on physical laws, makes the device virtually invulnerable in terms of failure. In this case, the probability of failures in work is close to zero;
  • low cost. This indicator applies not only to the device itself, but also to the costs of its operation. They are simply not available, since the device does not need a power supply or any additional elements that need to be replaced;
  • resistance to temperature changes;
  • security. The device is absolutely harmless to both human health and plants, as it does not require the use of dangerous devices (for example, PET) or toxic components.

There are hydraulic cylinder and disadvantages:

  • the principle of the mechanism does not allow to install it on the side vents;
  • there is no possibility to use the device for opening doors because of its low power. Also, it is not suitable for use in too large greenhouses;
  • with a sharp decrease in air temperature, the liquid inside the device does not cool down immediately (the cooling period is approximately 15-25 minutes). As a result, cold air will flow through the open air vents throughout this time, which may harm the plants.

Automatic air vent using hydraulic cylinder

Important! Before installing the device, make sure that the window in the greenhouse opens easily.

To install a hydraulic cylinder for greenhouses do it yourself will need the following tools:

  • electric drill or screwdriver;
  • screws or screws;
  • hydraulic cylinder

Installation steps:

  1. The hydraulic cylinder with one paw is attached to the greenhouse frame.
  2. The second paw of the device is fixed on the frame window.

If the diameter of the rod and the volume of the cylinder are calculated correctly, the height of the stem extension will reach 40 cm when the temperature of the liquid varies from +10 to +30 degrees. This is usually enough to open the transom.

Automation with shock absorber

To automatically open the vents, you can use the old automobile shock absorber, with which the following procedures are necessary:

  1. It is necessary to cut the ball located at the end of the cylinder, while leaving the maximum possible length of the hemp on which it was attached.
  2. The cylinder is clamped in a vice. In order not to damage it, it should be clamped behind the end part.
  3. At the end of the cut part of the cylinder (that is, in the stump to which the ball was attached) a hole 3 mm in diameter is drilled.
  4. ATTENTION! When drilling out of the cylinder, the air is drastically expelled, with the result that chips can get into the eyes. Therefore, during this procedure is to use safety glasses.
  5. On a stump the carving is cut.

The cylinder is ready to use. It works on the same principle as the hydraulic cylinder.


As you can see, the independent equipment of the greenhouse with an automatic ventilation system is a simple matter, and it is quite possible for any owner.Having done this work once, in the future you will save yourself from unnecessary difficulties in growing crops.