How To Identify Hydraulic Cylinder Seals

Inside of your hydraulic cylinders, at that place are a number of seals that perform of import functions, keeping your cylinders working efficiently while protecting internal components from beingness damaged by contaminants, corrosion, and other factors. These frequently-overlooked components are i of the most important parts of your hydraulic system — in fact, without those seals, your systems wouldn't work at all.

While you lot'll well-nigh never come across these hydraulic cylinder seals during performance, it's important to be familiar with the dissimilar types of seals that your machines use. When you know the function of each seal, as well as the differences between the materials used to fabricate hydraulic cylinder seals, you'll ensure that your equipment will not merely be best suited for its intended function just that it will also stand the exam of time.

Types of Hydraulic Cylinder Seals

Hydraulic cylinder seals can exist divided into ii big categories: Static and dynamic. Static seals are used in situations in which the component parts aren't designed to experience relative movement. These seals include O-rings, D-rings, backup seals, and other seals that are intended to remain in a fixed relative location.

1 kind of static seal is usually found where the piston and the rod join. A static piston seal sits inside the piston with the rod running through it. The pressure from the rod creates an impermeable seal that prevents hydraulic fluid from existence pushed through to the other side of the piston. This is specially important in single-action pistons, which only accept hydraulic fluid on one side of the piston.

Dynamic hydraulic cylinder seals, on the other hand, are intended for areas in which there is relative motion between 2 components. Considering at that place are a number of different functions performed by dynamic seals inside your hydraulic cylinder, it'south probably all-time to await at some of the specific seals you're probable to come across in greater detail.

Piston Seals

Piston seals provide the ability for your hydraulic cylinder past preventing hydraulic fluid from flowing by your piston. This makes piston seals one of the most important hydraulic cylinder seals in your organisation.

The seal formed by a piston seal keeps contact between the piston and the cylinder bore, helping to control the motion of your cylinder and keeping your cylinder at the same position when at residue — even when it'southward nether a load.

Piston seals can be either single- or double-activeness. Every bit mentioned earlier, a unmarried-action piston has hydraulic fluid on only 1 side of the piston, which means that the piston seal must remain extremely close to the bore, otherwise fluid tin can seep through and lessen the effectiveness of your cylinder.

Double-interim cylinders, as the name implies, have hydraulic fluid on both sides of the piston. Because of this, the shape of a double-acting piston seal is symmetrical, possessing the same sealing properties in both directions.

These seals can also allow for more clearance betwixt the piston and the cylinder bore, every bit they are not designed to prevent fluid leakage.

Rod Seals and Buffer Seals

Rod seals perform two seemingly contradictory functions. Beginning, they keep hydraulic fluid from leaking outside of the cylinder during operation. Nevertheless, these seals are likewise responsible for ensuring that there is a sparse layer of lubrication on the piston rod. This not merely prevents corrosion but also lubricates other important parts of your cylinder.

Depending on the duty level of your cylinder, yous may or may not too take a buffer seal, which is set farther within the cylinder, past the rod seal. These hydraulic cylinder seals are intended to smoothen out the pressure level within your cylinder, preventing pressure peaks resulting from external factors. They as well foreclose any contaminants within the cylinder, such as metal flakes, from causing damage to your rod seals.

Wiper Seals

Sometimes referred to as dust seals, excluders, or scrapers, wiper seals protect your equipment by preventing contaminants from entering your cylinder every bit the piston rod retracts.

Since the piston rod is coated with a sparse layer of fluid to forestall corrosion, it can too pick up clay and other contaminants, which could rapidly impairment the interior components of your cylinder. Wiper seals go along these contaminants exterior of your system.

Guide Rings

These seals are intended to maintain moving parts in the proper position throughout the process of relative motion. In improver to keeping the important components properly aligned, guide rings prevent whatever metal-on-metal chafe that might occur during performance, preserving the life of your equipment.

These seals also add another level of protection against contaminants by keeping your more sensitive seals prophylactic from added wear.

Materials Used for Hydraulic Cylinder Seals

Hydraulic cylinder seals tin be manufactured from a number of dissimilar materials. Each material has different properties that make them amend suited to unlike conditions, including loftier pressures and temperatures, equally well equally caustic chemicals. Hither are the different materials yous're likely to see:

Rubber

Safe seals are used in situations that require a high degree of flexibility and compressibility. Nitrile butadiene rubber (NBR), fluoroelastomer (FKM), and hydrogenated nitrile butadiene prophylactic (HNBR) are all commonly used to fabricate dynamic cylinder seals. They possess good resistance to grease, mineral oils, and other hydraulic fluids.

PTFE

Polytetrafluoroethylene (PTFE) offers superior immovability under extreme weather condition, including temperature, force per unit area, and caustic chemicals. PTFE also has a very depression coefficient of friction, which ways that information technology requires less lubrication than other seals and tin actually function quite well in dry out operation.

Rigid Plastics

Encompassing a wide range of materials, plastic hydraulic cylinder seals offer moderate resistance to temperature and force per unit area, as well as chemical reactivity.

The durability of a plastic seal is largely dependent on the quality of the material itself, which tin range from engineered plastics, which are superior to commodity plastic, to high-performance plastics. Because they take less flexibility than rubber or PTFE, these seals focus more than on adding strength to your cylinder.

Thermoplastic Elastomers

Thermoplastic elastomers, or TPEs, combine the forcefulness of plastic with the flexibility of rubber, which means that they stand up to loftier utilize while besides providing superior elasticity. These hydraulic cylinder seals are highly resistant to abrasion and tearing and will maintain a constant pressure for longer than other materials can.

Choosing the Right Hydraulic Cylinder Seals

Choosing the correct seal is about more than materials, still. In that location are a number of external factors that you demand to consider when you're designing your cylinders. Each of these factors tin become a long way toward determining which hydraulic cylinder seals you'll need to ensure that your system can piece of work efficiently for the long haul.

Cylinder Application

I of the most important considerations to keep in heed every bit y'all're designing your hydraulic cylinder is to know precisely what yous will demand your cylinder to exercise. In full general, you can break your application downward into iii different categories:

Light Duty: Pressures up to 2,300 psi, temperature up to lxx˚ C
Medium Duty: Force per unit area up to 3,625 psi, temperature up to 90˚ C
Heavy Duty: Pressure level up to 5,800 psi or more, temperature over 90˚ C

Having realistic expectations about the duty level that you'll require from your cylinder will ensure that you won't end up having to supercede your equipment prematurely. If you're unsure where your cylinder falls, or if you lot retrieve you're right on the dividing line between two service levels, it's commonly a expert idea to choose a heavier-duty model — but in case.

Temperature

Yous'll need to know your average operating temperature, but also the temperature of your equipment when it's at residue.

Speed

This is the speed at which your piston operates within your cylinder. Typically, the faster the cylinder operates, the hotter the cylinder volition become.

Fluid Pressure

Information technology's important to know what kinds of force per unit area your cylinder volition come across, which is usually expressed every bit a range. You'll as well want to identify any pressure peaks, noting both intensity and frequency.

Hydraulic Fluid

At that place is a wide range of different hydraulic fluids available, and each fluid possesses a dissimilar viscosity, which will affect the hydraulic cylinder seals you'll require.

Dimensions

The shape of your cylinder will besides take an bear upon on which seals you'll want to employ in your cylinder. You lot'll demand to know the exact measurements of these parts:

Rod diameter
Diameter diameter
Stroke length
Overall cylinder length

Each of these factors will play a office in determining other considerations, including pressure, speed, and ability. These tin can go a long way in helping you cull the right hydraulic cylinder seals to keep your equipment working properly.

MAC Hydraulics

No affair what your hydraulic arrangement needs, MAC Hydraulics is here for y'all. Our squad of experts can answer all of your questions about hydraulic cylinder seals. And our highly trained technicians will make sure that y'all get the data you need.

We're always happy to offer you on-site repairs for any problems you encounter, every bit well as preventative maintenance to ensure your hydraulic systems continue working at height performance.

We have all-encompassing experience in a number of industries, including food and potable, structure, manufacturing, and waste matter management. If you're looking for a trusted partner to help you with hydraulic services, contact united states today!

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