As a solution team, hydraulic cylinders are virtually as widespread as pumps and motors merged. So if you work a lot of hydraulic equipment, it really is very likely that cylinder mend price is a significant part of your overall operating expenses.
In accordance to some scientific studies, up to twenty five% of mechanical gear failures are failures of style. If we implement this to hydraulic cylinders, then as many as a single in 4 hydraulic cylinders are not adequately created for the software they are operating in.
This isn’t going to indicate that the cylinder is not going to do the job asked of it, it will – but not with an satisfactory service lifestyle. So if you have any cylinders that do not very last like they need to you may possibly need to tackle a single or a lot more of the subsequent 4 problems:
#one. Bent Rods
Bending of cylinder rods can be brought on by insufficient rod diameter or substance toughness, incorrect cylinder mounting arrangement or a mix of all a few. As soon as the rod bends, deforming load is put on the rod-seal. This raises leakage and eventually benefits in premature failure of the seal.
The allowable rod loading for a cylinder in an present software can be checked utilizing the Euler formula.
#two. Rod Finish
The surface end of the cylinder rod has a important impact on the daily life of the rod seal. If the floor roughness is too lower (smooth), seal daily life can be reduced as a consequence of insufficient lubrication. If the surface roughness is way too higher, contaminant ingression is increased and an unacceptable level of leakage earlier the rod seal can consequence.
In pnevmatske cevi of extending cylinder service lifestyle, consider of the cylinder rod’s surface area as a lubricated, put on-surface and treat it accordingly.
In some apps, the use of an alternative rod area treatment with exceptional mechanical qualities to conventional difficult-chrome plating, this sort of as nickel-chrome plating or High Velocity Oxygen Fuel (HVOF) metal spraying, can enhance the service life of the rod and its seals.
And in some circumstances, the set up of a shroud or bellows to protect the rod area and its seals from influence hurt and contaminants, can manage similar daily life extension positive aspects.
#three. Ballooned Tubes
Ballooning of the cylinder tube is normally caused by inadequate wall thickness and/or substance strength for the cylinder’s functioning pressure. Once the tube balloons, the appropriate tolerance among the piston seal and tube wall is lost, permitting substantial-force fluid to bypass the seal. This large velocity fluid can erode the seal and localised heating induced by the strain fall throughout the piston minimizes seal existence-the finish outcome of which is: premature failure of the piston seal.
#4. Insufficient Bearing Spot
If the surface area of the bearing (use) bands in the gland and on the piston are inadequate to adequately assist the aspect thrust transferred to the cylinder, abnormal load is put on the rod and piston seals. This benefits in deformation of the seals, and in the long run, their untimely failure.
Mend or Redesign?
To summarize the previously mentioned: not all hydraulic cylinders are created equivalent. So if you have any hydraulic cylinders that suffer recurring failure, it’s very likely that layout modifications are essential to break the vicious circle of failure and fix.