Hydraulic seals and pneumatic seals are designed as per the cylinder working pressure, cylinder speed, operating temperature, working medium and application. By rolling the ring on an inspection cone or dowel, the inner diameter surface can also be checked for small cracks, particles of foreign material, or other irregularities that cause leakage or shorten the life of the -ring. Also known as scrapers or dust seals, hydraulic wipers are crucial to preventing damage to other system components. The most common hydraulic seals are piston seals and rod seals, which are both cylinder seals with a flexible lip that rubs against the housing or shaft for improved sealing during linear movement. Hydraulic seals are relatively soft, non-metallic rings that are constructed using materials such as polyurethane, rubber or PTFE. Hydraulic seals are different in that they are typically used in liquid or oil, whereas pneumatic seals operate in environments of compressed gas. Most packings and gaskets used in aircraft are manufactured in the form of -rings. The earliest hydraulic system, invented by Joseph Bramah in England during the Industrial Revolution, made use of leather seals to achieve the same results as modern hydraulic seals made of polymeric materials. Most replacement seals, for most applications can be found off the shelf and seal kits for well known applications can be picked up easily. Real Seal manufactures and distributes seal products and mechanical components with a strong focus on performance oriented rubber and plastic materials. 9. Prevents system collapse: By preventing leakage, the flow of fluid can be monitored, and as a result of it, the system can prevent from collapsing. Instead, they are used to maintain the concentricity of the rod in the bore so that the other sealing elements can function properly and don’t wear unevenly. Good dimensional elasticity to ensure faultless operation even with working eccentricities between the rod and the housing or the piston and the cylinder wall respectively, as well as expansion of the cylinder due to operating pressure. Custom manufacturer of seals for hydraulic system applications. UK Seals’ Hydraulic & Pneumatic range caters for the full range of duty cycles. Bonded seals are composed of an elastomeric seal that is adhered to a metal washer for high pressure applications. Urethane seals enjoy wide application as rod scrapers and other dynamic seals in high pressure hydraulic hose, which further attests to its strength and its ability to take abuse. This wiper can also be used as a secondary seal to trap slight leakage from the primary seal. Manufacturer of standard and custom seals, including hydraulic silicate and phosphate gaskets. Hydraulic Zone offers a diverse range of standard and special type cylinders to suit all types of industrial cylinder applications. In some cases, however, replacing hydraulic seals does become necessary. Seals made with these and other elastomeric materials are usually fabricated through extrusion, although Teflon seals are sintered in an oven from a powder form. Applications include: Hydraulic Oil, Petroleum Base, Silicone oil and grease, Mineral and vegetable oil and grease, Aliphatic hydrocarbons (fuel, butane, propane, natural gas), Aromatic hydrocarbons (benzene, toluene), Chlorinated hydrocarbons (trichlorethylene and carbon tetrachloride), Chlorine Water, Gasoline, Fuels, Liquefied Petroleum Gas (LPG), Natural Gas, Propane, Diesel Oil, High vacuum, ozone and weather. In our stock you will find piston seals (PK3 and PK4), u-rings (UN, D2 and D3) and wiper seals (MW, ME1 and ME2). Also known as Gland seals , Headbush or Neck Seals, Rod seals act as a pressure barrier to maintain and regulate the operating fluid in a cylinder. Coming in two different compounds, nitrile and polyurethane, our comprehensive line of u-cups are ideal in rod and piston applications. Chromex launched a new compact range of hydraulics seals designed to meet the majority of your needs. Rod Seals are deliberated to be the most substantial component of a cylinder sealing configuration. Dynamic Seal: A dynamic seal is installed within the inner shaft of the hydraulic cylinder. But that simple, inexpensive hydraulic seal can cost you thousands in downtime and loss of production if it fails.
In this case, a combination of PTFE composite seals and wipers would be used to ensure superior sealing performance and a long service life. Cutting edge technologies include multiple sealing lip systems, shock-load resistance, low friction and ultra-dry capability. The distinctive types of sealing positions and directions that are used for hydraulic and pneumatic seals are axial seals, rod or internal seals, external or symmetric seals and piston seals. There are many pieces of equipment that require precise motion control and sealing within the medical industry, and with ever-increasing technological developments, the demand for specialist sealing materials and products will only grow. The lip can also scrape any contaminants from the rod surface, giving them the title of double-edged wiper seals”. The four-lobed design provides twice the sealing of a standard -ring, but requires less squeeze to maintain an effective seal. These wipers provide excellent performance on rods or rams in hydraulic and pneumatic applications. It should also be noted that while all hydraulic seals are important, not every single one is equally important. Allied Metrics is a leader among hydraulic cylinder seal manufacturers. Wear Rings are used to retain the piston centralised. No. 3 – Chemical breakdown of the seal material is most often the result of incorrect material selection in the first place, or a change of hydraulic system fluid. Lip seals are made of many different elastomeric materials, including polymers, plastics and rubbers, and they are effective in providing a seal in revolving machinery and equipment. The wiper is not a pressure sealing element. For the vast majority of hydraulic applications, hydraulic seals are a non-optional component; it simply isn’t practical or reasonable to manufacture and use systems which do not use a number of hydraulic seals. Hydraulic cylinder Piston seals are a variation of the rod seals available as single-acting or double acting based on the capability to seal dynamic pressure either on one side or both sides. Wiper seals scrape dirt, chips or moisture from the piston rods as it them into the retract to the system. This allows to match the seal to many different types of cylinders, without making quality and price compromises. They are used to prevent the hydraulic fluid from flowing across the piston, from leaking past the interface between the rod and the head and to keep it from leaking to the outside of the cylinder. RTA Rod Seals: These Single Acting seals are used in hydraulic cylinders that have small groove dimensions. Make sure you confirm all relevant compliance issues for general use of hydraulic seals in your application, as well as identifying any relevant standards based on industry, application, environment, etc. A lubricant in the space between the sealing lip proper (primary lip) and additional (secondary) lip can reduce wear and delay corrosion. Hydraulic seal manufacturers generally fabricate seals from rubber or metal, and in some cases leather or felt. We supply wipers, rod u-seals, rod buffer seals, piston seals, wear rings, U-seals, vee packings, individual vee rings & adaptors, piston cups, T seals, piston assemblies, piston seal assemblies, piston rings, wiper rings, oil seals, ‘’ Rings, backup rings, quad rings & retainer rings, as well as bushes, teflon bushes & self aligning bearings for the cylinder eyes. Given the working conditions found in many of these industries, these seals need to be built to withstand high pressure. American Seal & Packing Loaded Lip Seals are molded from 92 Durometer Urethane with a 70 Durometer Nitrile energizer. Toughest of the elastomers used for -rings, characterized by high tensile strength, excellent abrasion resistance, and tear strength. Scrapers or Wipers scrape dirt, foreign particles, chips or moisture from the piston rods as they retract into the cylinder, preventing contamination. Piston seals are dynamic hydraulic seals that are used to prevent the passing of any fluid beyond the piston as the system pressure forces the piston down the cylinder.
Balanced seals are seals that are designed to reduce the effects of hydraulic pressure in the seal compartment. Hydraulic Seals go far beyond preventing fluid leakage. Other polymer materials specified for your application. The symmetric seal is used for simple linear operations wherein the cross section of the seal is symmetrical, and this makes it an interchangeable option for rod and piston seals. Offers pump seals for hydraulic fluids with up to 2400 psi pressure, up to 14000 rpm speed, and -40 to 450 degrees F temperature. T-seals are also employed as replacements for existing -rings. Hydraulic seals can be made from a variety of materials such as polyurethane, rubber or PTFE. Applications include: CR is resistant to refrigerants, ammonia, Freon® ( R12, R13, R21, R22, R113, R114, R115, R134A), silicone oils, water, ozone, vegetable oils, alcohols, and low-pressure oxygen. A wide selection of sizes and alternate compounds allow this profile to match up with many hydraulic applications. While using the seal removal and the installation tools, contact with cylinder walls, piston heads, and related precision components is not desirable. Rod seals are used in hydraulic and pneumatic cylinders to seal the system pressure on the rod side against the atmosphere. The tee seal has two nylon back-up rings that are anti-extrusion devices and this allows for the T-seal to function under much higher pressures than a standard -ring. The classification of hydraulic seals is possible, based on function and design. Although static seals vary by number and exact location depending on the specific cylinder structure, all of them serve the purpose of closing gaps between immobile surfaces. The choice of wiper seal should be made based on the choice of piston and rod seals. Nitrile u-cups come in 70, 80 and 90 durometers and are ideal in low pressure, hydraulic and pneumatic cylinders. WCA Wiper Seals: Featuring a corrosion-resistant metal ring that encompasses the NBR seal, these Heavy Duty seals follow the side movement of the rod to keep it free from heavily deposited dirt. Over time however, it is expected that hydraulic seals will eventually need replacing, this can be down to general wear and tear, improper installation or exposure to extreme elements. At Allied Metrics, we offer our customers a full range of high-quality seals suitable for numerous applications. Whereas conventional seals are manufactured from leather, neoprene, rubber or fabric-reinforced elastomers, DEPAC puts its trust in polymer material. Wiper Seals:Also called wipers or scrapers, these prevent dirt, chips, and moisture from entering the piston rods, as they retract into the hydraulic cylinder. They are made with different profiles and materials and protect the cylinder head against possible leakage of liquids or gases. And, hydraulic wipers scrape moisture, dirt and other foreign particles from the piston rods as they retract into the cylinder. The Rod Seal is the seal in the hydraulic cylinder with the most demanding requirement specifications. In that sense, prioritization is important when selecting and applying different types of hydraulic seals. An additional consideration for hydraulic applications is that sealing components are often required to perform in higher temperatures, as well as return to their original dimensions after a sustained period of dynamic motion. A wiper helps prevent dirt particles from entering the hydraulic system. Not only must the hydraulic seals prevent leakage of fluid from the Cylinder, but hydraulic seals must also withstand high pressures, extreme temperatures and transverse forces within the cylinder. The edge of the sealing lip and the shaft counterface form the most important functional area of a radial shaft seal. By keeping everything from dirt to moisture outside of the system, scraper seals prevent any damage to rods, cylinder walls, seals and other important elements of the system. By reworking old bores and extending the life of cylinders, the inside clearance widens and changes the seal specifications. Hydraulic seal failure in medical applications can cause serious problems, ranging from inaccurate drug dosages to critical malfunctions with artificial hearts.
A detailed understanding of the challenges seals will face in their exact operating environment is essential for an accurate specification, with different elastomer materials offering radically different performance characteristics across a range of parameters. Hydraulic seal installation varies depending on the nature of applications. We have an inventory of military and industrial seals (-rings, back-ups, hydraulic seals, thred-seals, stat-seals and all types of packing seals for hydraulic and pneumatics). Its outstanding tear resistance and abrasive resistance result in its slippery surface properties that make it advantageous for use in seals in moving systems such as mass spectrometer probes and valves. Static Hydraulic Seals are positioned in a housing where there is no motion involved, they are sealing only within their limited space. Fitted into the small spherical bearing housing, the RTA seals are combined with an NBR -ring and PTFE inner to maximize sealing resistance against even the highest pressure. Most often, they’re used to power linear actuators, hydraulic cylinders, and pistons in internal combustion engines. These extreme examples might not be commonplace, but they serve to highlight the importance of using high quality sealing solutions designed for the specific demands of such critical environments and applications. Hydraulic cylinders use water, oil or other pressurized fluids to facilitate the movement of heavy machinery. They also serve to protect the rod seal from any contaminants that do manage to find their way into the cylinder (such as metal chips). Single-acting piston seals for use in older type industrial hydraulic cylinders. This leads to scoring on the cylinder and piston rod (expensive repairs), leaks and environmental problems. Rod Seals are also referred to as shaft seals sometimes. Vulcanizing is an excellent solution for non-standard sized -rings and seals delivering greater strength and tolerances. Designed for medium duty applications and can provide both wiping and sealing action in one component in low pressure systems. For continued sealing effectiveness and long seal life, the surface finish of the working surface of either rods or bores should be a maximum of 16 micro-inches. In order to maximise longevity and functionality in specific applications, hydraulic seals are made from a wide range of materials, each with their own unique properties. Hydraulic seals (also referred to as hydraulic cylinder seals or shaft seals) are devices designed to keep fluids from escaping from cylinders or pumps while simultaneously preventing foreign contaminants from entering them. Leather and reinforced materials absorb hydraulic fluid. It’s difficult to pin down specific accessories for use with hydraulic seals, due to the extremely wide range of applications, industries, and types to consider. Piston Seals fit onto shafts with the sealing lip contacting the housing bore. There are two main types of hydraulic seals: static, which seals within a confined space like a gasket , and dynamic, which is exposed to movement on its inner diameter, usually around a shaft of some kind. Usually, hydraulic seals are located on the cylinder head, on the rod shaft, or in the piston. Hydraulic Seal – Allied Metrics Seals & Fasteners, Inc. Polymeric seals make for an easy, inexpensive, replaceable, effective barrier to fluids. Some particular types of hydraulic seals (e.g. bonded seals) are made from metallic materials (including brass, bronze, aluminum, carbon steel, and stainless steel). Therefore, Rod Seals function in conjunction with Wiper Seals to guard a hydraulic configuration against outer contaminants including dust, dirt and outside atmospheric circumstances. Whether it is small or large diameter, low or high pressure, reciprocating or rotary motion, dynamic or static sealing, a suitable product for your application is available. Since 2007 we have been making getting -rings easy by continuing to improve our people, product and process. General-purpose compound suitable for applications requiring resistance to aromatic or halogenated solvents or to high temperature (-20 to 260C with limited service to 315 degrees C). Outstanding resistance to blended aromatic fuels, straight aromatics, halogenated hydrocarbon and other petroleum products.
B-type loaded U-cup hydraulic seals are used for dynamic reciprocating applications. An example of weighing these different factors can be seen in the hypothetical selection of -rings. They use oil seals (or metric oil seals outside of the United States) that are made of resistant materials like Teflon, silicone, polyacrylate or a fluroelastomer that can handle continuous exposure to oil. Fluid Power Seals are special PTFE seals designed for use as either piston or rod seals and are activated by an elastomer -ring. Back-up rings prevent extrusion of the -ring when it is subjected to high pressures. Rod seals work together with wiper seals to protect a hydraulic system against external contaminants such as dirt and outside weather conditions. These seals are important for maintaining the piston position at rest and to control the motion of cylinder. Wiper seals or scraper seals plays an important role in preventing the entry of external contaminants such as moisture, dirt, and dust to the hydraulic system or cylinder assemblies. Our design process consists of working closely with you to understand the sealing requirements and then applying our design expertise and joint test program to develop the right sealing solution that improves your products sealing performance. Seal House can machine Rod Seals to suit almost any application. Wear rings guide the piston and piston rod within the hydraulic cylinder, absorbing transverse forces, preventing metal-to-metal contact. Nitrile – For applications with temperatures up to 250°F (Nitrile seal elements) with two Nylon or PTFE back-ups are recommended. Wear Rings:They guide the piston and piston rod within the cylinder. A type of dynamic hydraulic seal called a piston seal is exposed to movement on its outer diameter along the tube or bore of a hydraulic cylinder. Sealing Devices offers a complete line of Parker -rings, Polypaks, hydraulic seals, and sealing materials from stock, and is a Certified Parker Sealing Technology Center. This allows pressure build up on one side of the piston, making the cylinder extend or retract. Hydraulic systems are sealed using a combination of specialized seals. The reliable high performance of hydraulic seals is very important to applications in the medical industry. Additionally, with the implementation of our computerized numerical control (CNC) machine, we are able to create high quality hydraulic seals and have them ready to ship in a fraction of the time. Manufacturer of hydraulic seals and guides in several profiles or designs and in a wide range of series and sizes, making them appropriate for a variety of operating conditions and applications. Custom designed PTFE seals for unique applications. Rod seals prevent leakage of fluid from within the cylinder. Non-positive actuated anti-extrusion devices for use down stream from single and double-acting rod or piston seals. They also prevent metal-to-metal contact, optimizing the performance of the sealing system and increasing the seals’ lifespan. The buffer seals attenuate the pressure fluctuations to improve the rod seal performance. We offer a wide range of hydraulic seals designed to suit the cylinder working pressures, always taking the speeds, operating temperature and application into account. Hydraulic wipers prevent contaminants, such as water, dust and debris, from entering the cylinder assembly and hydraulic system. Hydraulic rod seals prevent fluid from leaking outside the cylinder. RFD Rod Seals: Also known as Single Acting Split Housing, these are heavy duty seals that also include an anti-extrusion ring for added protection. Sealing specialists Novotema, are well-versed in specifying the correct elastomer materials for medical application requirement, as well as a wide range of other life science industries. Commonly, wiper seals are constructed using the component polyurethane. Hydraulic applications in power transmission equipment and in control systems have become extremely popular over the years thanks to their efficiency. So, if you have an application that can be solved or improved by installing a hydraulic seal, consult a manufacturer today.