71059 second-hand spare parts for public works equipment



Spare parts, Hydraulics : 301 products

Hydraulics: without it no movement!

What would our machines be without the hydraulic system? We would have stayed with the mechanical models with their crossover of wiring, pulley block, lattice arrows, span and limited lifting force. Codimatra, specialist in the sale and purchase of second-hand equipment and spare parts, has selected for you a complete range of quality hydraulic products: rotary joint, hydraulic drive motor, rotation gearmotor, oil cooler, etc.

The hydraulic circuit of a machine is in comparison with another extraordinary machine that is the human body, the blood and muscle circuit of public works equipment.

The main pump, the hydraulic distributor, is the blood system, the heart of the machine. The pump allows the pressure and hydraulic flow to be produced thanks to the energy of the diesel engine, which, directed by the driver from the joysticks of his cab driving the valve, will bring force and power to the blade cylinders, bucket cylinders, boom cylinders.

As you will have understood, the blood of the machine is the hydraulic oil. A real vital fluid, it ensures the transmission of movements requested by the operator via the cylinders. This oil must be low viscosity, it is often monograde in 10W. It limits the heating of the moving parts and cavitation of the pumps.

Pumps, valves, VCMs, cylinders are machined parts, closely referred to as microns of clearance tolerance. This is why it is important to change the oil, replace the filters regularly and inspect the seals and moving parts. It should not be forgotten that the hydraulic system operates at pressures of about 350 bar for one excavator, at a flow rate of 400 litres per minute.

Any particle of sand, metal, dust can have a catastrophic abrasive effect. It should be noted that a large particle of 15 microns can damage the operating clearance of a hydraulic part with a tolerance between 10 and 15 microns, which is 10% of the size of a human hair!

Also the manufacturer's hydraulic oil filters have a treatment fineness of 5 microns. For such sharp adjustments, it is not uncommon for manufacturers specializing in miniaturization to turn to hydraulic parts.

This is the case of Kawasaki, known for its high-performance motorcycles, but also of Rexroth, Poclain, Caterpillar and JCB, known for their know-how in construction equipment. A piece of advice that is worth its weight in gold: always remember to carry out an oil change, a dialysis clean-up and an operating cycle with special depolluting filters when replacing any component in the hydraulic circuit. You will save on the lifetime of your circuit and therefore of your equipment.

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