APSOseal® Stroke seals

The essential elements of fluid power control

The countless ways of utilizing power by fluid circuits could not be feasible without these key parts. Stroke seals are single or composite devices utilized to maintain the fluid separation (either liquid or gaseous) between two chambers of either the hydraulic or the pneumatic actuators. In this way, fluids flow only through the defined paths  and transfer the power according the machine's purpose.  In most cases, the actuators in which they are built-in produce reciprocating motions (strokes), but in other cases, they can produce angular oscillations, too. To satisfy this spectrum of dynamic applications, a comprehensive range of designs is needed. Depending on the specific function, a range of different seal types can be used that are categorized as Piston Seals, Rod Seals, Rotary Seals, Wipers, and Guide Rings.

Stroke seals are most popularly used in the sealing systems of hydraulic and pneumatic cylinders designed for automatic machines, presses, power steering systems and agriculture machines. Other more sophisticated applications include different sealing systems for either heavy-duty hydraulic cylinders (like the actuators for construction equipment) or for other devices like fluid flow control by dozing valves used in the Food & Beverage, Pharma, and Chemical Processing Industry.

But the primary sealing function is only one requisite an effective and reliably performing stroke seal needs to fulfill, as other features are essential, too.
 

Material knowledge is a key factor for high performing seals

Be it a rubber or a plastic seal, choosing the right materials can provide proper chemical inertia against the media in contact, correct physical performance against the working temperature and the working pressure, and the necessary tribological properties to offer low friction and high abrasion resistance.

A wide range of PTFE compounds, but also Polyurethane and other elastomers like NBR, HNBR and FKM compounds are available at Angst+Pfister for either lubricated or dry working conditions. And according to the application, they can be designed for self-energizing, with rubber energizing components, and with steel springs. 

It goes without saying that best solution for your sealing application can be achieved by making use of our highly specialized competence in the area of materials. Together with our engineering know-how for conceiving the most effective stroke seal design, this makes for a recipe for success!
 

Finalizing the effective solution

Working pressure, speed, dimensional constraints, working temperature, chemical composition of the media to be sealed, low friction, and long endurance are all conditions that an effective solution needs to satisfy. Angst+Pfister has developed the specific expertise over a century of activities across different OEM industries to support you in defining the most suitable sealing solutions.

Angst+Pfister offers a comprehensive range of standard normalized sealing items shown in the table below, as well as the possibility of co-designing customized devices to fully meet even the most stringent customer’s requirements for demanding applications. Our engineering and product application specialists aim to provide leading-edge technology and valuable solutions for all your hydraulic and pneumatic applications. Get in touch with us now!