Single Acting Hydraulic Cylinder Design
Single-acting cylinder: In a single-acting hydraulic cylinder, the working hydraulic oil only enters the rodless cavity. The working hydraulic oil entering the rodless cavity can build pressure on the piston surface, so that the hydraulic cylinder piston rod extended. Under the action of the return spring, the piston rod weight or the external force, hydraulic cylinder piston rod retracts.
When thrust is required in only one direction, a single-acting cylinder can be used; After the pressure stroke, need the load or other external force to make the piston return. Such as spring return, when using the spring return stroke, the load and friction coefficient should be considered, and explain that the spring causes the piston rod to extend or retract. The spring-returned single-acting cylinder has a longer overall length than the general double-acting cylinder.
For tie rod hydraulic cylinder of single-acting spring cylinders, It is recommended to extend the length of the tie rod, so that the spring pre-pressure can be completely released when the cylinder is disassembled.
For single-acting cylinders that are generally retracted by their own weight or reset by external force, set up a seal on the hydraulic oil pressure side to form a closed space, the other side is only a guide support belt and exhaust port. Others are no different from general double acting hydraulic cylinders.
Conventional front spring single acting cylinder, the cylinder is extended by oil pressure, relies on spring force when retracting. Spring single-acting hydraulic oil cylinder. The extension of oil cylinder is the superimposed force of oil pressure and spring. This kind of single-acting oil cylinder is rare but does exist. The design point of this type of cylinder is the choice of spring. There are also many calculation software available now. The selection of wire diameter and pitch should be adjusted according to the specific external dimensions.
In the plunger hydraulic cylinder, the piston and the piston rod constitute a single actuator. Due to the structural limitation of the plunger cylinder, the piston rod can only be retracted under the action of external force. Therefore, the plunger cylinder can only be installed vertically.
Plunger-type single-acting cylinder: There is only one fluid chamber. This type plunger hydraulic cylinder is usually installed vertically, and the load reset causes the cylinder to shrink. They are called "displacement cylinders" and are practical for long strokes;
This kind of plunger cylinder generally has a thicker piston rod, no piston, and only seals at the guide sleeve. Generally, the guide sleeve has a longer stroke and is longer than other cylinders. There is no restriction on the position of the oil port. There is a row at the bottom of the guide sleeve. The air valve is generally located above the hydraulic cylinder.
After the above introduction, do you have a general understanding of single-acting cylinders?