The hydraulic steering is nowadays wide used in almost every domain of the industry. Elements of the hydraulics are the basic equipment of machines and of mechanisms in such branches as the agriculture, mining, building and many other.

The popularity of the hydraulics is especially connected to the huge ease of the automation and of the steering in some basic motion parameters of executive elements , that is in hydraulic cylinders. The machinist by means of the lever (of the dividing valve) steers the direction of the oil flow and consequently steers the work of hydraulic actuators.

In hydraulic cylinders the energy contained in working liquid that is the oil under pressure is exchanged into the mechanical energy – the plane turning motion of the piston. In such a way we obtain the possibility of lifting or displacing elements with mass exceeding even several tones.

Such machines as trailers, dumpers, excavators, elevators and cranes, thanks to the utilization of the hydraulics, became easy in operating, being able to transport huge masses in a single time unit. It shortens considerably the time of the exercise in many agricultural, building, of road and many other works.

Hydraulic piston type actuators are double-acting, in which the working factor (oil under pressure) acts alternately on both surfaces of the piston causing the out-slide and the return of the piston. The machinist steers the direction of the oil flow by means of the dividing valve (a lever).

Technical data of piston type actuators manufactured by “PRONAR”
1. The nominal pressure: 16 MPa
2. The working factor: hydraulic mineral oil with viscosity 10 – 300 cST
3. The sensitivity threshold (starting pressure): 0,5 MPa
4. The maximum speed of pistons: 0,5 m/s
5. The range of the operating temperature: 253K – 353K (-20oC +80oC)
6. The required exactitude of the filtration of the working factor: 0,02 mm (20µm)

Hydraulic plunger type actuators are single-acting devices in which the working (oil under pressure) factor is brought to the cylinder with only one pipe causing the plunger outflow. The return of the plunger is realized by means of springs or under other external power.

The run-off of oil to the container takes place consequently within the pipe. The direction of the oil flow is steered by the machinist by means of the dividing valve(a lever).

Technical data of the plunger type actuators applied in agricultural machines “PRONAR”
1. The nominal pressure: 16 MPa
2. The working factor: hydraulic mineral oil with viscosity 10 – 300 cST
3. The sensitivity threshold (starting pressure): 0,5 MPa
4. The maximum speed of pistons: 0,5 m/s
5. . The range of the operating temperature: 253K – 353K (-20oC +80oC)
6. The required exactitude of the filtration of the working factor: 0,02 mm (20µm)

Hydraulic telescopic actuators are made of several cylinders, following gradually with smaller diameter, assembled one in the next and advancing in turn. It is possible, in such a way, to obtain the large stroke, at the small length of the complicated actuator.

In hydraulic telescopic single-acting actuators the oil under pressure acts on one side causing the protrusion of individual elements of the actuator. The return of the telescope is realized under an external power (most often under the weight of the unloading trailer box). The inflow and the run-off of oil takes place consequently within the pipe. The direction of the oil flow is steered by the machinist using the dividing valve (a lever).

Technical data of telescopic actuators manufactured by “PRONAR”
1. The nominal pressure: 16 – 18 MPa,
2. The number of elements: 2,3,4,5,
3. The working factor: hydraulic mineral oil with viscosity 10 – 300 cST,
4. The sensitivity threshold (starting pressure): 0,5 MPa,
5. The maximum speed of pistons: 0,5 m/s,
6. The range of the operating temperature: 253K – 353K (-20oC +80oC),
7. The required exactitude of the filtration of the working factor: 0,02 mm (20µm)

Only a few European companies can produce hyraulic telescopic cylinders of double acting. One of them is PRONAR. Our own construction with modern technologies are guarantee success and reliability work. This cylinders have wide range in modern agricultural machinery and building machinery.

Technical data of double acting telescopic cylinder manufactured by „PRONAR”
1. The nominal pressure: 20 MPa,
2. The number of elements: 2
3. Working factor: hydraulic mineral oil with viscosity 10 – 300 cST,
4. The sensitivity threshold (starting pressure): 0,5 MPa,
5. The maximum speed of pistons: 0,5 m/s,
6. The range of operating temperature: 253K – 353K (-20oC +80oC),
7. The required exactitude of the filtration of the working factor: 0,02 mm (20µm)

Hydraulic pipes are applied to such liquids as: mineral oils, water-oil emulsions, water solutions of glycol and water in the range of temperatures from -40˚C to +100˚C and within service pressures given in PN-91/C-94250/60 and in tables for every particular type of tips. Tips with a hydraulic hose can be aggregated in any set, possessing technical features according to the agreement with an ordering client.

Lengths of pipes and the position of tips are dimensioned as follows:
– eye type
– sigle
– angular

We measure the position (the angle) of two angular tips of the pipes in mutual relation measuring the angle from the tip behind the pipes to the front tip (figure above).

The Company PRONAR is able to realize the production of stiff hydraulic pipes.

Pipes can be made of:
• the black (later painted)steel pipe;
• the steel galvanized pipe;
• tubular stainless/acid-resistant steel;
• the copper-pipe;
• the aluminum-pipe.

Pipes are designed for the nominal pressure 16 MPa and the extreme pressure 32 MPa. They can be made of any configuration and with any type of connecting tips.
Bending of pipes is made within two systems:
• bending at the constant ray – the ready pipe is made of bending parts (arcs) and straight sections among them;
• bending with the variable ray – one can obtain any ray of the pipe.
It is possible to prepare a pipe with constants and variable rays. We are also able to bend the rectangular tubing.

The outsider tube diameter [mm]	Constant ray [mm]	Variable ray MIN [mm]	Straight section MIN [mm]
6	12	48	50
12	21	96	50
14	25	112	60
15	45	120	60
16	48	128	50 lub 60
20	35	160	110
20	55	160	110
21,4	56	172	110
25	70	200	110
28	80	140	85
30	65	240	110
30	85	240	110
35	100	280	110

The straight section MIN means the minimum straight section between following curves. The variable ray MIN for the given pipe cannot be smaller than the 8 times value of the diameter of the pipe (of the value of the variable ray MIN given in the table).

Hydraulic pointing is a part of the hydraulic pipes. They are made of tips, a hose, a terminal sleeve and a nut, or also of a tip and a terminal sleeve. Connecting parts are made of steel and protected against the corrosion with the zinc-electrolytic coat . Tips cooperating with the external or internal cone are made as:
1. L – the low-pressure version
2. H – the high-pressure version
Ordering the chosen type of a tip, you can present only its catalogue designation. It is also possible to realize the order on a client wish, with connecting elements of the forcible hydraulics not existing in the catalogue, applied in the mining, in the engineering industry etc.

The connecting elements are applied to join pipes and steer and executive elements in hydraulic control systems. Pronar produces different types of single attachment, both in metric and inch systems. The double attachments are also produced in a wide range of the nominal diameters. PRONAR, also, is able to produce any type of connecting elements in accordance with the documentation presented by an ordering client.

Containers of compressed air produced by PRONAR are used in pneumatic braking systems. Such systems are at present applied in goods vehicles, farm machines, buses etc. The compressed air is a source of energy necessary to the insertion of brakes. This compressed air is stored in a container having needed capacities. The driver steers the inflow of the compressed air to brake-mechanisms. The high quality of the containers produced by us is testified by the certificate CE and by the norm EN 286:2:2001 according to which they are produced. PRONAR offers a wide range of containers with diameters from D=145mm to D=396mm, and capacities from 5 dm3 to 100 dm3.

They are intended to be used in braking systems with the maximum working pressure PS=12,5 bars and with the maximum operating temperature Tmax = 100˚C. Stub pipes for containers are made within standards utilizing a thread of M22x1.5, or, on a client wish, utilizing a thread G1/2″. The containers are painted with the powder method.

Pneumatic and Hydraulic Department provide services:
– professional selection of hydraulic cylinders;
– machnining;
– bendig of stiff hydraulic pipes;
– pointing of hydraulic and pneumatic pipes;
– RAL colours painting with individual customer wishes;