What is the "crawl" of the execution component in the hydraulic system?
Poor lubrication condition. When sliding speed decreases, the oil wedge is weakened, the thickness of the lubricating oil film is reduced, and even some oil film ruptures, causing the metal surface to contact. When the sliding speed to a certain value, the oil membrane rupture rate increase, the friction force increase, friction coefficient increases to a certain value, after sliding vice appear alternately "pause a sliding a pause" phenomenon, namely the so-called "crawl". Therefore, the failure of lubrication, lubrication system, or the failure of the guide surface to be scratched (too much or too little) can cause the oil amine to burst and creep.
The invasion of air in the system is an important reason for the crawling. Once the air is in the oil, the compressibility increases. Double piston rod oil cylinder driven platform, the guide surface has friction with the piston and oil cylinder. When the left cavity enters the pressure oil, the piston must overcome all the static friction forces in order to move the workbench movement and not move immediately. At this point, the working fluid compresses the air in the left cavity and gathers energy until it can overcome the static friction resistance and the workbench moves. Once started, the static friction turns into friction, the left cavity is compressed air, and the energy of the original deposit is released quickly, and the workbench is rushed forward. In this case, the return of the oil cavity is increased, causing the right lumbar air to be compressed, the back pressure increases, prevents the workbench movement, and then pauses after the shock. Because of the constant input of the pressure oil in the left cavity, the front and the back are constantly circulating and the workbenches are crawling
Mechanical rigidity, improper loading and distortion of parts, abrasion and size of parts can cause friction to creep. The sealing of oil cylinders, pistons and piston rods is too tight, too loose or leaking; Piston and the piston stem different heart, piston rod bending, piston and cylinder bowls of relative wear, taper cylinder body, ovality super poor will cause uneven friction resistance produced by crawling.
