Hydraulic seals are essential components found in a wide range of systems—from industrial machinery and construction equipment to aerospace and marine applications. These small but powerful components seal the openings in hydraulic cylinders and systems, helping to control and maintain fluids and internal pressures.
Hydraulic seals are used in many sectors, including:
- Industrial machinery
- Construction equipment
- Automotive applications
- Agricultural equipment
- Aerospace Applications
- Marine vessels
- Medical equipment
- Renewable energy
Iron Wing has created a comprehensive guide covering everything from how hydraulic seals work, the various seal types, to key factors for choosing the right seal for your needs.
Types of Hydraulic Seals
Static Seals
Static seals are used in stationary applications to prevent hydraulic fluid leaks. These seals are commonly found in areas such as cylinder heads, pipe joints, valve seats, and similar parts. Examples include O-rings and gaskets.
Dynamic Seals
Dynamic seals are used in applications different from static seals. They serve as barriers for moving parts, ensuring the system remains sealed. Common components that utilize dynamic seals include pistons, rods, rotating shafts, and other moving parts. Rod seals and piston seals are both common types of dynamic seals used to prevent fluids from leaking, playing a vital role in avoiding external leakage across the parts’ hydraulic systems.
Wiper Seals (Scraper Seals)
Wiper seals, also known as scraper seals, block external contaminants from entering hydraulic systems, protecting internal components from dirt, dust, and moisture. These contaminants can cause significant damage to the seals and other components.
Buffer Seals
Buffer seals are used in high-pressure hydraulic systems. They are designed to provide the most secure seal for the sliding movements between the cylinder head and piston rod. These seals protect the rod seal from high-pressure spikes and sudden fluid pressure changes. In addition, the thin lubrication film on the seal safeguards the piston rod against corrosion and keeps the rod and wipers lubricated.
Key Factors for Selecting Seals
Material
The material used for the seal is an important factor to consider. Understanding the properties of each material will help you make the right choice. Whether the seal is made from nitrile rubber, polyurethane, or another material, each offers a unique benefit suited to your application.
Pressure Level
The seal you select must be able to withstand the pressure it will face in its proper application. Otherwise, you risk the seal breaking, deforming, wearing, or failing. Consider the system’s normal operating pressure and its peak pressure levels. Even if these pressure spikes last only a moment, they can greatly impact the seal’s performance and lifespan.
Temperature Range
Not all seals can withstand high temperatures or extreme cold. That’s why it’s important to know the material of your seals and the temperatures they can handle. Also, consider both the resting and operating temperature ranges when selecting your seal.
Size
Before selecting a seal and its ideal size, it is recommended to refer to your hydraulic manual first. The size of your cylinder or part will help to determine the size of the seal needed. Check the compatibility and size information of the seal before purchasing to ensure it matches your application. A seal of the wrong size will either be too large to fit into the application or too small, allowing fluids to leak through.
Fluid Compatibility
The type of fluid your application is carrying is important to consider when selecting the right seal. Your hydraulic system is likely mainly water-based or oil-based. Different seals, each made from different materials, will be used depending on the fluid in your system.
Application
Consider the application of the seal, determining whether it will be used in an indoor or outdoor environment, and whether it will be exposed to dry or wet conditions. Environmental factors and exposure to harsh conditions can wear down your seals more, which may influence your decision when selecting your next seal.
Hydraulic Seals & Parts at Iron Wing
Proper maintenance, accurate knowledge, and a thorough understanding of your hydraulic machinery are essential for selecting the correct seal for your application. Looking for replacement seals or parts for your hydraulic system? Iron Wing has you covered! We carry a large range of parts for heavy-duty truck, heavy equipment, industrial, marine , forklift & lift equipment, and more. Our hydraulic inventory includes pumps, motors, cylinders, hoses, filters, and more! Search our store by part #, description, or manufacturer and easily filter your results!