Difference between Single-acting Piston Seals And Double-acting Piston Seals

Single-acting piston seals and double-acting piston seals have different functions. You need to choose the right piston seal to achieve the desired sealing effect. Jinwoseal will introduce the specific differences between the two in this article.

1. Definition and applicable direction

Single-acting piston seal

• Definition: A seal that provides sealing function only in one direction (single side).

• Working principle: The seal is designed to prevent high-pressure media from leaking from one side to the other side, but does not provide sealing in the opposite direction.

• Applicable scenarios: Single-acting hydraulic cylinders or cylinders, such as equipment where the push rod only applies force in one direction.

Double-acting piston seal

• Definition: A seal that can provide sealing function in both directions (both sides).

• Working principle: The seal can prevent the leakage of high-pressure media in both directions at the same time, and is suitable for systems that withstand bidirectional pressure.

• Applicable scenarios: Double-acting hydraulic cylinders or cylinders, such as industrial machinery, lifting equipment, and other equipment that require bidirectional movement of the piston.

2. Design and structure

Single-acting seal

• Sealing lip shape: Usually only one lip contacts the cylinder wall, and the design is relatively simple.

• Installation form: The installation direction is strong, and the lip must face the pressure direction to achieve the sealing effect.

• Common forms: U-shaped seals, O-rings, etc.

Double-acting seals

• Sealing lip shape: There are sealing lips on both sides, which can seal in both directions at the same time.

• Installation form: Symmetrical design, no need to distinguish the direction, more flexible installation.

• Common forms: Symmetrical U-shaped seals, combined seals, sliding ring seals, etc.

3. Performance comparison

Attributes	Single-acting seals	Double-acting seals
Sealing direction	One-way sealing	Two-way sealing
Structural complexity	Simple structure	More complex structure
Installation requirements	Need to pay attention to directionality	Symmetrical design, no special requirements for installation direction
Applicable scenarios	Unidirectional force equipment	Bidirectional force equipment
Cost	Low	High

Summary

The selection of single-acting piston seals and double-acting piston seals should be determined according to the working mode and pressure requirements of the equipment. Single-acting seals are suitable for simple equipment working in one direction, while double-acting seals are suitable for equipment with bidirectional force and complex working conditions. When selecting the seal, you also need to consider factors such as system pressure, media type, temperature and speed to ensure that the performance of the seal matches the equipment requirements. It is recommended that you communicate with Jinwoseal's experienced consultants who will provide you with a cooperative sealing solution.