mechanical seal diagram manufacturer

Depending on your specific needs and application, Flexaseal can help you identify the ideal products. Contact us to tell us about your needs and request a quote.

The scope of our mechanical seal product range far exceeds any other seal manufacturer. From small elastomer bellows seals used in millions of domestic water pumps to double mechanical seals that ensure maximum sealing safety and large, highly customized dry-running gas seals for mission critical high speed turbo compressors, John Crane has the right product for any application.

Our world-class rotating equipment technologies, paired with an unmatched breadth of applied engineering expertise, meet virtually all international standards including API 682 and help plants reduce maintenance costs, slash down time and improve reliability. When it comes to keeping your rotational equipment running 24/7, John Crane’s comprehensive range of mechanical seals and systems has you covered.

A range of seals for mission-critical applications, designed to solve the application-specific challenges of each industry. From API 682 compliance for the oil and gas industries, using gas seal technology on our innovative pump gas seals to eliminate fugitive emissions, dealing with slurry in the mining and minerals processing industries, to the difficulties associated with maintenance on large pumps and rotating equipment — we have a solution.

Dry-running, non-contacting gas seals have been the industry standard since the early 1980s for turbomachinery. John Crane gas seals, separation seals and support, monitoring, control and conditioning systems — the heart of any reliable sealing solution — are constantly evolving to meet the needs of customers. The product portfolio is supported by unrivaled global service capability providing repair, retrofit, gas seal storage and reliability expertise, delivering total solutions throughout the product lifecycle.

In industries like chemical, pharmaceutical, pulp and paper, and food and beverage, safeguarding and compliance with industry standards, avoiding contamination and efficiency are always top priorities. Our range of vessel and agitator seals optimize equipment performance, maintain product purity and conform to industry regulations, no matter where you are.

Our range of mechanical seals, packing and bearing isolators combines advanced, thoroughly proven technologies with extensive industry expertise to create a range of products characterized by innovative design concepts and outstanding manufacturing quality. Tried, tested and effective solutions for virtually any application that deliver robust performance, reduced installation times and lower maintenance costs.

Create the optimum operating environment that will ensure outstanding seal performance and reliability. Our comprehensive range of engineered pressure reservoirs, gas seal control panels, heat exchangers and abrasive separators can be combined to produce the perfect seal support system for any application.

Designed to overcome rigorous challenges, our comprehensive suite of seal face technologies combat limited seal face lubrication that adversely affects reliability, cost and durability. Our engineers designed these face treatments to extend rotating equipment life through advanced micro machined patterns and features improving seal face lubrication that optimizes equipment performance. We deliver the right face technology for the right application.

... pressurized gas barrier metal bellows seal utilizing APGS non-contacting seal face technology. Welded metal bellows eliminate dynamic O-ring hang-up in a compact cartridge that fits ANSI and DIN standard ...

• Drive mechanisms external to the product;• Seal faces positioned for maximum protection;• A dynamic elastomer moves on a non-metallic surface, eliminating fretting defects;• Hydraulically balanced;• Cartridge easy to ...

Burgmann H74-D Mechanical Seal called as PC04 are specialized in mechanical seals products. This device gives double seal and it can be rotated in any ...

The MTM10-11 is a conical spring mechanical seal developed by Microtem. It is mainly used for general services machinery at low and medium pressure. This unbalanced mechanical seal ...

The MTM 25_26, manufactured by MICROTEM, is a conical spring mechanical seal that can compensate positioning errors and withstand stresses created by vibrations. The contact surface can be made with silicon ...

... agitators on sealed tanks will have a mechanical seal of some sort. For many sanitary process vessels, the mixer must have some type of sealing barrier to provide either a dust tight vapor seal, ...

mechanical seal for automotive engine cooling water pump, referred to as water seal, mainly composed of two parts: rotating ring and static ring. Static ring is installed in the pump ...

The 3-D Seal is designed to be the foremost solution for high radial misalignment and high run out applications. By combining Garlock’s proven P/S®-II and expansion joint technologies into ...

Aura™ reduces operational and transactional costs using a patented polymeric sealing device. Aura reduces leakage rates by up to 15 percent, lowering the total cost of operation while protecting the environment. An enhanced rotor design ...

The AESSEAL® API Type A, B and C single-seal range offers the user an unprecedented range of API engineered sealing solutions to suit all application ...

Mechnical seal type 5030 / 5031 »with rubber bellowssingle-actingnon-anisotropicAreas of usestandard pumpwaster water pumpsupply engineeringgeneral industrial usemass production seal

When purchasing the units, if left hand rotation, special seal, or a particular position of cartridge (shaft end or cover end) is needed, it should be ...

Cartridge Seals by CinchSeal are customized mechanical seals for rotary air locks in bulk handling equipment. They are designed to replace lip and packing seals in screw ...

A.W. Chesterton® is a manufacturer of industrial fluid sealing and maintenance products including hydraulic seals, pneumatic seals, mechanical seals and packing, oil seals, o-ring seals, metric seals, lip seals and many other products. We are ISO 9001/14001 and MRP II Class A certified.

AccroSeal® is committed to manufacturing high quality seals to your design at competitive prices. The AccroSeal® technical sales team works directly with your engineering department to solve the most difficult sealing applications. Our sealing product portfolio includes wipers, lip seals, o-rings, piston rings, v-rings, and more produced from our exclusive Accrolon® engineered compounds.

American High Performance Seals Inc. designs and manufactures hydraulic seals, rotary shaft seals, oil seals, gaskets and other high performance rubber and plastic parts. AHP Seals designs and manufactures the most durable seals available and delivers them within 1-4 days.

Since 1981, American Seal Supply Co. has been distributing top-quality fluid seals and packing to its varied customer base. Among our product offerings are oil seals, rubber seals, o-ring seals, metric seals, Teflon® seals and lip seals. We also supply hard-to-find and custom-made seals.

American Seal & Packing is a leading manufacturer & distributor of mechanical seals, Grafoil, gasket material, cut gaskets and quality o-rings. We are constantly working to provide innovative solutions to mechanical seal problems. With our wide selection of products we"re finding better ways to serve our customers all the time. Contact our expert staff for a quote to meet your needs.

Appleton Packing and Gasket was born out of the need for better service. Among the many products we offer are mechanical seals, oil seals, gaskets, mechanical packings and o-rings. We attribute our success to the trust placed in us by our customers. Our continuing goal is to offer outstanding quality products at competitive pricing, in a manner which will best satisfy customer needs.

Beacon Gasket & Seals Co. is fully tooled to cut your requirements from compressed non-asbestos, gylon, gore-tex, flexible graphite, teflon, silicone, red rubber and neoprene rotary seals and other hydraulic sealing systems. Specializing in MTBF Solutions and representing the best manufacturers in the industry, we are excited about our expanding product offerings and the opportunity to serve you.

CoorsTek provides custom engineering, materials expertise, operational excellence and rapid execution to make our world measurably better! Technical ceramic, engineering plastic and specialized metal components help us build tomorrow’s technology. CoorsTek hydraulic seals offer extreme-temperature, high-pressure, chemically inert, static and dynamic seals for the most demanding applications.

CW Marsh offers you the best of both worlds: the toughest, most versatile natural material available for sealings and the benefits of a century of technological advancements and product innovation. CW Marsh produces leather vee packings, cups, u-packings, flanges, and back-up washers, all manufactured and backed with the same old-world dedication to quality, service and dependability.

At D&D Engineered Products Inc. we manufacture top of the line hydraulic seals, gaskets, various o-rings, high temperature tapes, compression packings, and much more. We promise to cater our product to any needs you may have, such to ensure your satisfaction. If you would like more information please give us a call.

East Texas Seals, Inc. is a distributor of O"Rings and Gaskets for Parker Seal. If you need an O"Ring, Seal or Gasket, we can fulfill your needs. We have supplied the Oil Field industry with O"Rings to adequately keep their oil rigs up and running. East Texas Seals, Inc. works closely with the U.S. Government and Defense departments, shipping and storage companies and all commercial sectors.

EPM, Inc. is your one stop shop for seals, with billions of styles including rod seals, piston seals, symmetrical seals, V-Rings, wipers, rotary shaft seals, wear rings, static seals, back-up rings, o-rings, buffer rings, u-cups, oil & grease seals, cast iron piston rings and gaskets. Whether you need one or one million, EPM offers fast turnaround and great prices on seals up to 21inches or 600mm.

With an extensive customer service center for catering to customer needs, Freudenberg-NOK manufactures a number of different seals. These offerings include hydraulic seals, pneumatic seals, o-ring seals, rod seals, piston seals and pump seals.

Garlock Sealing Technologies is the global leader in high-performance fluid sealing products for the world’s processing industries. Their 12 manufacturing facilities in the U.S., Canada, Europe, Asia and Latin America collectively produce the broadest range of fluid sealing products designed specifically for industrial applications. Some products include metal gaskets, o-rings and oil seals.

Here at Gasket & Seal Fabricators, we supply die cut, lathe cut, extruded, molded and spliced gaskets of all types, sizes and shapes. We specialize in both commercial and military spec materials, including many UL, FDA and NSF recognized materials. Our in-house capabilities include various types of die cutting equipment such as punch presses, both manual and automatic roll feed, clicker presses, and beam presses. Contact us for more information!

We manufacturer high quality hydraulic seals that are ideal for a wide range of industries. Here at Global O-Ring and Seal, LLC we are a trustworthy manufacturer who is known for our ability to adhere to all of your special requests. These seals come in a number of different materials including Buna, Viton, Silicone, Teflon, Aflas and more. Please give us a call today to learn more!

We are a preferred supplier to most of the leading global manufacturers of hydraulic equipment, air compressors, transmissions, hydraulic clutches, valves and shock absorbers. We manufacture hydraulic seals and pneumatic seals among other products. Let us work together to enhance your applications.

Over 100 years, Hallite Seals International has been at the cutting edge of fluid power technology, manufacturing a wide range of rod / gland, piston, and static seals, as well as support and bearing components, for technically challenging applications, from a wide range of materials which include Polytetrafluoroethylene (PTFE), Polyurethane (AU), nitrile rubbers (NBR) and Fluoro-elastomers (FKM).

For over 34 years, Harwal has continued to be the leader in metric oil seals. With one of the largest seal selections, 1,000,000 seals in 7,000 different sizes in stock, be assured we"ve got what you need. We also offer V-rings, standard inch sizes, end caps, Teflon® seals, wipers and gamma seals!

For over 34 years, Harwal has continued to be the leader in metric oil seals. With one of the largest seal selections, 1,000,000 seals in 7,000 different sizes in stock, be assured we"ve got what you need. We also offer V-rings, standard inch sizes, end caps, Teflon® seals, wipers and gamma seals!

Hi-Tech Seals is capable of either creating parts with our in-house machining department or utilizing our relationships with industry leading seal manufactures. Our sales staff works with customers to find the best solution to replicate existing or design new parts. Different manufacturing options include machining, molding and extrusion.

At HydraPak, we make replacing your hydraulic seals easy, so you can get your seal repair jobs completed quickly, saving you time money. Even the most difficult seal repair challenges can be handled by our knowledgeable staff to get your equipment. We offer expertise in products for high-tech applications, as well as the ability to source everything from o-rings to sheet goods to sealing devices.

Being a seal manufacturer and distributor, JEM Seal Co. offers mechanical seals, hydraulic seals, oil seals, rubber seals, and more. Our mining equipment industry seals are used exclusively by Hallite Mining. Our stock of piston seals, rod seals, and wipers are in stock for your specific needs.

Encapsulated O-ring manufacturer and Precision extruder M-Cor Inc. is a leading U.S. producer of high performance sealing products for extreme environments. Extruded profiles are converted into o-rings, Teflon® encapsulated o-rings, camlock gaskets, chemical transport tubing and other sealing products. With in house tooling capabilities, we are able to immediately respond to customer requests.

Martin Fluid Power distributes on a worldwide basis, hydraulic seal repair kits, o-ring seal repair kits, metric seals, Teflon® seals and a lot of other types of seals, plus gaskets and packing. Our products come in many different shapes, sizes, materials and colors to suit your specifications.

Speed is of the essence at Michael-Stephens Co. Within 24 hours of your request, we can customize nitrile oil seals for you in a variety of profiles and materials. We work with a wide range of Teflon®-filled items. We also supply hydraulic seal kits; our website lists the wide range of manufacturers we carry.

Pacific International Bearing is capable of providing solutions for all types of applications with an educated and committed staff here to service your needs. PIB offers quality seals from Chu Hung Oil Seals Industrial Company (manufactured in Taiwan). They hold ISO 9001 Quality Certificates to provide top quality oil seals. Seals come in a variety of sizes and lip designs to suit your need.

With over 175 years of accumulative sealing experience, this team has helped pioneer the development of high performance seals around the world. Our core people excel at innovative seal design, high performance materials utilization, and efficient production techniques with a Certified ISO 9001: 2000 and AS9100 Rev. Some products of ours include, rotary shaft, rod and piston seals.

We are not only technically knowledgeable about hydraulic seals, but we also have the hands-on experience to back it up. We have over 30 years of industry experience, and we can use that experience to benefit you. We have faced nearly every problem and know the right solution for most problems. We can offer both stock and custom seals to benefit you. We will always put the customer first, so contact us today!

R&B Plastics is a supplier of custom machining serving a variety of industries including electronic connectors, plastics, filters, bearings, hydraulics and valve seals. With 34 years experience, R&B Plastics provides quality products to both the U.S. Government and major aerospace companies such as Boeing Corporation.

R.T. Dygert International is one of the largest distributors located in Minneapolis, MN and an office/warehouse in Niles, IL. RT/Dygert International prides itself on its responsive, service-driven culture and its reputation for its core values of quality, honesty and integrity and committed to a process of continuous improvement. Some of the products include piston and rod seals and o-rings.

Seal Master® specializes in manufacturing custom-built inflatable seals. These products include metric seals and rubber seals available in different sizes and shapes. Our seals are used in a wide variety of applications, including valves, robotics, conveyors, gates, brake devices and actuating devices.

Established in 1979, Southwest Seal and Supply has grown to become one of the most predominant distributors of sealing, hydraulic hoses, fittings, couplings/connectors, gasketing and fluid control products in the Southwest. We offer a wide range of products including the best in selection, quality, and value-added services.

System Seals offers a complete range of industrial hydraulic seals: small or large diameter, low or high pressure, reciprocating or rotary motion, dynamic or static sealing. We carry in-stock standard sizes plus are flexible enough to cater to all sizes. Rod Seals, Piston Seals, wipers & guide elements.

The T-Bird Group is a collection of distributors and manufacturers of seals, bearings, v-packings, unified pistons, wear rings, wipers, wear strips, u-cups, and machined plastic components.

Texacone Company, Inc is a manufacturer of fabric-reinforced elastomer and urethane molded products. Texacone specializes in molded seals up to 65" diameter in solid or split from a wide variety of fabric-reinforced elastomers. High temperature materials also available. Some of our products are: v-rings, flared u cup, piston cups and flanges.

At ROC Carbon, we’re pleased to manufacture carbon/graphite mechanical seal faces from your drawings or samples, using the same high-quality materials and tolerances that are found in original equipment manufacturer parts. As experienced mechanical face seal manufacturers, our team at ROC is experienced in machining intricate details such as flow channels and ports. Our lapping capabilities encompass both carbon and hard faces up to 16 inches in diameter and to as flat as 1 helium light band. We can insert the carbon seals in metal housings (machined by us or furnished by you) by heat shrink fitting or by using specialty high-temperature adhesives.

Our Mechanical Seals are used in a wide range of pumps and rotating equipment worldwide to prevent liquids and gases escaping into the environment. We manufacture mechanical seal types to suit all industries and our investment in modular design means that we provide the best on-time delivery performance in the industry.

The AESSEAL® range of seals, seal support systems and bearing protectors are all designed to improve pump reliability and reduce maintenance costs. Our business is built around giving our customers such exceptional service that they need never consider alternative sources of supply.

AESSEAL® operates from 235 locations in 104 countries, including 9 manufacturing and 44 repair locations, and has more than 300 customer service representatives who visit industrial plants every day. Find Out More..

We offer a range of standard inventory cartridge mechanical seals, including single and double seals to suit even the most demanding application and thanks to our modular design system we offer them with the best on-time delivery performance in the industry.

For unusual applications our Standard Plus seal range offers all the benefits of a standard seal while meeting our customer’s specific needs. This covers competitor replacement seals, seals designed for specific pumps and seals designed for pumping specific processes.

Cartridge mechanical seal construction is a proven reliability improvement. The seals are pre-assembled at the factory, pressure tested and shipped as a unit, leading to improved performance as errors due to incorrect installation are reduced. Cartridge construction eliminates the need to measure and set spring compression, and having a mechanical seal pre-assembled means that the seal faces are protected from damage during installation.

A mechanical seal is simply a method of containing fluid within a vessel (typically pumps, mixers, etc.) where a rotating shaft passes through a stationary housing or occasionally, where the housing rotates around the shaft.

When sealing a centrifugal pump, the challenge is to allow a rotating shaft to enter the ‘wet’ area of the pump, without allowing large volumes of pressurized fluid to escape.

To address this challenge there needs to be a seal between the shaft and the pump housing that can contain the pressure of the process being pumped and withstand the friction caused by the shaft rotating.

Before examining how mechanical seals function it is important to understand other methods of forming this seal. One such method still widely used is Gland Packing.

The stationary part of the seal is fitted to the pump housing with a static seal –this may be sealed with an o-ring or gasket clamped between the stationary part and the pump housing.

The rotary portion of the seal is sealed onto the shaft usually with an O ring. This sealing point can also be regarded as static as this part of the seal rotates with the shaft.

One part of the seal, either to static or rotary portion, is always resiliently mounted and spring loaded to accommodate any small shaft deflections, shaft movement due to bearing tolerances and out-of-perpendicular alignment due to manufacturing tolerances.

The primary seal is essentially a spring loaded vertical bearing - consisting of two extremely flat faces, one fixed, one rotating, running against each other.  The seal faces are pushed together using a combination of hydraulic force from the sealed fluid and spring force from the seal design. In this way a seal is formed to prevent process leaking between the rotating (shaft) and stationary areas of the pump.

If the seal faces rotated against each other without some form of lubrication they would wear and quickly fail due to face friction and heat generation. For this reason some form of lubrication is required between the rotary and stationary seal face; this is known as the fluid film

In most mechanical seals the faces are kept lubricated by maintaining a thin film of fluid between the seal faces. This film can either come from the process fluid being pumped or from an external source.

The need for a fluid film between the faces presents a design challenge – allowing sufficient lubricant to flow between the seal faces without the seal leaking an unacceptable amount of process fluid, or allowing contaminants in between the faces that could damage the seal itself.

This is achieved by maintaining a precise gap between the faces that is large enough to allow in a small amounts of clean lubricating liquid but small enough to prevent contaminants from entering the gap between the seal faces.

The gap between the faces on a typical  seal is as little as 1 micron – 75 times narrower than a human hair.  Because the gap is so tiny, particles that would otherwise damage the seal faces are unable to enter, and the amount of liquid that leaks through this space is so small that it appears as vapor – around ½ a teaspoon a day on a typical application.

This micro-gap is maintained using springs and hydraulic force to push the seal faces together, while the pressure of the liquid between the faces (the fluid film) acts to push them apart.

Without the pressure pushing them apart the two seal faces would be in full contact, this is known as dry running and would lead to rapid seal failure.

Without the process pressure (and the force of the springs) pushing the faces together the seal faces would separate too far, and allow fluid to leak out.

Mechanical seal engineering focuses on increasing the longevity of the primary seal faces by ensuring a high quality of lubricating fluid, and by selecting appropriate seal face materials for the process being pumped.

When we talk about leakage we are referring to visible leakage of the seal. This is because as detailed above, a very thin fluid film holds the two seal faces apart from each other. By maintaining a micro-gap a leak path is created making it impossible for a mechanical seal to be totally leak free. What we can say, however, is that unlike gland packing, the amount of leakage on a mechanical seal should be so low as to be visually undetectable.

Power machines that have a rotating shaft, such as pumps and compressors, are generally known as “rotating machines.” Mechanical seals are a type of packing installed on the power transmitting shaft of a rotating machine. They are used in various applications ranging from automobiles, ships, rockets and industrial plant equipment, to residential devices.

Mechanical seals are intended to prevent the fluid (water or oil) used by a machine from leaking to the external environment (the atmosphere or a body of water). This role of mechanical seals contributes to the prevention of environmental contamination, energy saving through improved machine operating efficiency, and machine safety.

Shown below is a sectional view of a rotating machine that requires the installation of a mechanical seal. This machine has a large vessel and a rotating shaft at the center of the vessel (e.g., a mixer). The illustration shows the consequences of cases with and without a mechanical seal.

If the aim is solely to prevent leakage from the machine, it is effective to use a seal material known as gland packing on the shaft. However, a gland packing tightly wound around the shaft hinders the motion of the shaft, resulting in shaft wear and therefore requiring a lubricant during use.

To ensure this, each part is fabricated according to a precise design. Mechanical seals prevent leakage even with hazardous substances that are difficult to mechanically handle or under harsh conditions of high pressure and high rotating speed.

A mechanical seal is installed on the impeller rotating shaft. This prevents the liquid from leaking through the clearance between the pump body and the shaft.

The face materials where the stationary ring and the rotary ring rub against each other are the most important portions as a barrier to the fluid. If the clearance is too small, the friction increases, hindering the shaft motion or resulting in seal breakage. Conversely, if the clearance is too large, the liquid will leak. Consequently, it is necessary to control the clearance in the order of micrometers to prevent leakage, but at the same time ensuring lubrication by the fluid, thereby reducing the sliding torque and avoiding hindrance to the machines’ rotation.

The mechanical seal technology is a sum of mechanical engineering and physical property technology due to the above-mentioned functions and applications. More specifically, the core of the mechanical seal technology is the tribology (friction, wear and lubrication) technology used to control the surfaces where the stationary and rotary rings rub (slide) against each other.

Mechanical seals with improved functionality will not only prevent the liquid or gas handled by a machine from leaking to the outside, but also improve machine operating efficiency, thereby helping achieve energy saving and prevent environmental contamination. Moreover, in some cases, rotating machines handle media that, in the case of leakage, can lead to a dangerous accident. Therefore, mechanical seals are required to be highly reliable through manufacturing backed by solid engineering expertise.

These functions and roles will make mechanical seals increasingly important functional parts in the future. Their further technical innovation is anticipated. To positively respond to these expectations, Eagle Industry is working on technical research and development every day.

The mechanical seal technology was fundamentally established in the 1960s. Thereafter, it has been making significant progress by introducing various leading-edge technologies, and innovative mechanical seals created from the above advanced technology are continuously being put to practical use.

To meet the demands of the market sufficiently, an applicable range of the “pressure” and “rotation speed” of mechanical seals has been considerably extended since the beginning of the 2000s. This is due to advancing of the tribology technology such as to enhance a function of the sliding materials (e.g., composite material composition, coating technology) and/or a performance of the sliding surfaces based on the fluid lubrication theory (e.g., non-contact mechanical seal, surface textured mechanical seal). These advanced technologies are sustained by improvement in the element technology of numerical analysis, processing/production, physical property/composition analysis, measurement, verification test, and so on.

Manufacturing of Mechanical Seals involves high precision light engineering activity. Close tolerances have to be maintained on most dimensions and lapped surface finishes to a flatness measured in millionths of an inch are absolutely necessary for effective sealing. Most of the machinery are general purpose, such as lathes, drilling machine, milling machines, grinding machines, etc. In addition, lapping machines are

Due to varied operating conditions, mechanical seals have to be carefully selected for every application. Important parameters that influence selection and performance of mechanical seals are : Fluid properties, operating temperatures, pressures, shaft sizes and speeds, space availability for installation and the type of equipment on which the mechanical seals are mounted.

Through a detailed study of these parameters, and on the basis of engineering standards developed through extensive research and experience, appropriate seals are selected and detailed component drawing are made. These drawing

Carbon graphite materials are purchase in billet form with various O.D. and I.D. configurations. These materials are impregnated to seal the pores and increase chemical and wear resistance. Machining is performed on dedicated and modified engine lathes. Carbon graphite machining includes turning, boring and grooving operations, utilising carbide and diamond tools. Milling, drilling and tapping operations are performed on conventional manual type milling and drilling machines Carbon seal faces are finished, lapped and polished on standard lapping and polishing machine.

These operations are performed on all seal faces using conventional lapping and polishing machines and equipment with abrasive slurry, 30 micron and 6 micron diamond.

The welding operation is performed to connect the metal terminals to the metal bellow capsules made of 350 Stainless Steel and other type of materials. This welding operation is completed by the use of specialized welding equipment, and for the metal bellow type seals only. Other welding operation involves the welding of two piece gland ring made of 316 Stainless Steel or other type materials to obtain a steam heated gland

There are no by-products that result from the manufacturing process. The manufacture of mechanical seals is a light precision engineering industry ; no effluent or hazardous chemicals are involved in the manufacturing

A seal is required to keep lubrication in and contaminants out of a cavity where lubricants are stored - a "controlled seal cavity." The non-contact seal is designed specifically for applications where lubrication must be kept from leaking out of a controlled fluid cavity located between two elements.

A typical seal application involves a stationary element, a non-stationary (or rotating) element, and a controlled fluid cavity between these two elements (See Fig. 1). Traditionally, simple lip seals have been applied in this type of environment.

Initially, non-contact seals were developed as a sealing method that would operate in extremely high shaft speed environments, or in applications where the durability of a traditional lip seal was limited. The contact lip seal has the stationary sealing element, or lip, in contact with the rotational element. This constant contact creates wear on both the lip and the rotating element, and adds significant parasitic drag to the system. In addition, operating speed is limited in these applications due to overheating and wear on the contact lip of the seal, as a result of rubbing between the rotating and non-rotating surfaces. Ultimately the seal lip will melt or centrifugally lift from the contact surface as operating speeds increase.

Non-contact seals are designed to seal without any physical contact between the rotating and stationary elements. In general, the benefits of non-contact seals include:

The type of non-contact seal chosen for an application determines its specific benefits. The key to successfully employing any non-contact seal is to understand the sealing methods, and to select the appropriate seal configuration for each specific application.

Each type of seal has specific advantages and limitations. To determine the applicability of each seal, the engineer must examine the performance of the seal during each of three normal operating modes:

There are several types of labyrinth seals. Typical labyrinth seals incorporate a "maze" or a set of rings in extremely close proximity, to capture the lubrication and push it back toward the controlled fluid cavity. Rings in close proximity form a barrier by shearing the fluid, centrifugally slinging the lubricants from the rotating seal element to the stationary seal element in a series of steps (See Figure 2).

The labyrinth seal is constrained in its ability to function with a wide variety of fluids due to its limited ability to centrifugally push the lubricants back into the controlled fluid cavity. In addition, it can only handle a limited volume of lubricating fluid in the controlled fluid cavity, and it requires high rotational speeds to seal adequately. The seal is not able to keep out external environmental contaminants entering the controlled fluid cavity when the seal is not rotating, and some fluid "weepage" is expected from the seal. In general, the standard labyrinth type seals have limited abilities when reviewed in terms of the three operational modes:

When the seal is not rotating, the controlled fluid cavity is open to the outside environment. The fluid that is contained in the seal can migrate to the bottom of the seal and possibly weep out of the seal. The length of time the seal is stationary will affect the amount of weepage.

When the shaft is accelerating, the seal is accelerating and the fluid within the controlled fluid cavity must remain in laminar flow, or splashing will occur and the seal will leak. Splashing can be controlled somewhat by selecting a lubricant with high viscosity. The seal is designed to push the fluid back into the controlled fluid cavity, but it will also push any contaminants that have entered the stationary shaft into the controlled fluid cavity. The fluid level in the cavity must also be limited to ensure the fluid does not splash and flow past the seal.

When rotating at the normal operating speed, the labyrinth seal pushes any fluid trying to exit the controlled fluid cavity back into the seal cavity. The normal speed range required will depend on the specific seal chosen but, in general, high speeds are required to maintain consistent behavior. During operation, the seal is open to contaminants entering from the outside environment. The rotating element and the stationary element in the labyrinth seal must remain axially aligned during operation and any axial movement between the two elements or vibration in the application could cause the seal to leak.

The hybrid labyrinth seal has been modified by adding a contact seal component designed to centrifugally lift off the rotating shaft when the seal is operating at normal speeds. This modification solves some of the limitations of the standard labyrinth seal, and makes it function more like a contact lip seal. In addition, a lip seal component can be incorporated such that it will only make contact at lower speeds and will centrifugally lift from the contact surface at higher speeds. While the hybrid labyrinth seal does solve the problem of contaminants entering the controlled fluid cavity when the seal is not rotating, it adds challenges in mounting the seal

In general, the hybrid labyrinth type seals have limited capabilities when reviewed in the three operating modes, but in the proper applications they can perform adequately. Hybrid labyrinth type seals offer additional features over the standard labyrinth seal but still have some limitations:

When the seal is not rotating, the controlled fluid cavity is not open to the outside environment but some weepage is possible because the lifting mechanism must be capable of moving in and out radially. The fluid that is contained in the seal can also migrate to the bottom of the seal and weepage of fluid out of the seal is possible. The length of time the seal is stationary affects the amount of weepage.

When the shaft is accelerating, the seal is accelerating and the fluid within the controlled fluid cavity must remain in laminar flow or splashing will occur and the seal will leak. Splashing can be controlled on a limited basis by selecting a lubricant with high viscosity. The seal will also have some parasitic drag torque until the contact element in the seal is centrifugally lifted from the contact surface. The splashing problems from acceleration and deceleration will be similar to those of the standard labyrinth seal when the seal is operating at speeds high enough to centrifugally lift the contact element from the rotating shaft. Operating speeds are critical to ensure proper operation of the seal.

When rotating at normal operating speed, the hybrid labyrinth seal pushes any fluid trying to exit the controlled fluid cavity back into the seal cavity. The speed range required will depend on the specific seal chosen but, like the standard labyrinth seal, high speeds are required to maintain consistent operation. The seal is also open to contaminants entering from the outside environment, and the seal will push these contaminants into the seal cavity during operation. The rotating element and the stationary element in the labyrinth seal must also remain axially aligned during operation and any axial movement between the two elements or vibration in the application can cause the seal to leak.

Centrifugal pressure seals are non-contact seals that utilize a rotating chamber within the seal to develop internal pressures and pump the sealing fluid back into the controlled fluid cavity. (See Figure 3).

The double seal illustrated in Figure 3 will pump the contaminants out of the seal from the nonfluid side of the seal as well as pump the lubricating fluid back into the controlled fluid cavity.

The rotating chamber method significantly reduces the operational speed requirements of the typical non-contact seal and allows the use of extremely low-viscosity fluids, even water. The more fluid that passes from the controlled fluid cavity into the rotating chamber, the greater the pressure inside that chamber to return the fluid to the controlled fluid cavity. The fluid in the controlled fluid cavity will continue to fill the rotating chamber in the seal, until the pressure from the fluid in the rotating chamber is in balance with the pressure in the controlled fluid cavity. At this point the seal will continue to move fluid in and out of the rotating chamber to maintain a pressure balance with the controlled fluid chamber.

The centrifugal pressure seal is still a non-contact seal that solves the alignment issues of other labyrinth seals and actually pumps fluids to create a pressure differential between the environment and the controlled fluid cavity. This pressure differential also prevents contaminants from entering the seal"s fluid chamber. These advantages are not available in either the standard contact lip type seal or the labyrinth seals. The advantages are clearer when looking at the three operational modes:

In the double seal arrangement, the controlled fluid cavity is only partially open to the environment or the non-fluid side of the seal. If contaminants enter the non-fluid side of the chamber while stationary, they will be pumped out of the chamber upon acceleration of the seal. Due to the wrapped chamber design, fluid does not leak from the seal in the stationary operation mode.

When the shaft is accelerating or decelerating, the seal is not affected by any splashing of the lubricant. Splashing is prevented through a series of pumping discs located in the rotational chamber, which form a baffle to eliminate splashing and to keep the fluid in laminar flow at all times. The centrifugal pressure seal can operate with extremely low viscosity fluids such as water, without any leakage. Because the rotational chamber is located towards the outside diameter of the seal envelope and the fluid is captured in the seal rotational chamber, the seal is operable at much lower speeds than typical labyrinth seals. Splashing problems from acceleration and deceleration in the labyrinth seal are eliminated.

When operating at normal speed, the seal is pumping any fluid trying to exit the controlled fluid cavity back into that cavity. The speed range required will depend on the specific seal chosen but in general, high speeds are not required to maintain consistent operation of the seal. The centrifugal pressure seal pumps contaminants from the non-fluid rotational chamber into the outside environment. This contamination can be in a liquid or gaseous state; the non-fluid chamber will still pump any contaminants out of the chamber. The seal has the additional feature of pumping and producing a pressurized controlled fluid cavity while in operation. This feature allows the controlled seal cavity to be completely filled with fluid, and as long as the seal is rotating, the fluid will not leak from the controlled fluid cavity. The design does not require the rotating element and the stationary element to remain in precise axial alignment during installation, maintenance, or operation. Some motion is tolerable from vibration and alignment.

There are currently three types of non-contact seals available in the marketplace: the Labyrinth Seal, the Hybrid Labyrinth Seal and the Centrifugal Pressure Seal. All three seals offer differing technological solutions to a specific problem. The difficult part for the engineer is to define the requirements of each application and to select the proper seal to meet the specific needs of each design. This can be accomplished by reviewing the standard modes of operation for the seal types and reviewing the limitations of each design. The following table highlights some of the operating characteristics among the three seal designs:

When the proper seal is selected, the rewards are significant compared to a standard contact lip seal. These benefits include low maintenance cost; no down time due to seal wear/parts failure; extremely high efficiency by eliminating parasitic drag torque placed on the rotating shaft; and finally increased bearing life due to reduced heat generation.

©The Carlyle Johnson Machine Company, LLC and Centritec Seals, LLC., all rights reserved. Information contained herein is intended for illustrative purposes only. Individual projects and applications vary significantly and valves should be specified for specific applications.

Ashish Seals is one the of the major Reverse Balanced Mechanical Seal manufacturers, suppliers and exporters in Mumbai India. We are ISO 9001-2015 certified reliable manufacturer of Reverse Balanced Mechanical Seals that is designed to handle abrasive or corrosive media. As the metal components of this kind of seal do not come in contact with the media to be sealed, it is widely in demand. The offered mechanical seal is compact in design; hence neither axial nor radial extra space is essential for its installation. Such seals are used to handle hydrocarbons, corrosive chemicals, general & light chemicals.

Reverse Balanced Mechanical Seal is externally mounted and are multi coil spring seals. Liquid pressure is used for closing the seal faces. Thus, it is very useful in vacuum and high pressure applications. As it eliminates the shaft step or sleeves for balancing, this makes it a unique seal. It can be exceptionally useful light corrosive and contaminated liquid. The metal does not come in contact with the media. Such seals eliminate the elastomer’s movement. Hence it reduces fretting effect on shaft efficiency.

A crucial step in preventative maintenance in pumps is finding and using the correct seal for the job. Mechanical seals are used to seal the rotating shaft in pumps and other equipment. With so many mechanical seal designs on the market, it can be difficult to identify which kinds to use. A.W. Chesterton Company’s mechanical seal design utilizes 5 design principles to maximize its sealing capabilities. These principles have been refined by Chesterton since the company brought its first mechanical seal to market in 1970. After all the lessons learned from successes and failures, they have determined the Five Key Features that a mechanical seal should have to reduce unplanned maintenance and downtime. To provide the greatest mean time between failures (MTBF) and avoid downtime, they utilize these five design principles in their sealing devices.

Typically, within early mechanical seal designs, the springs were submerged within the fluid. However, this can lead to trouble when fluids with dirt or other contaminates interact with the springs. When the contaminates collect within the spring, it cannot correctly maintain the alignment necessary for a complete seal. Chesterton’s mechanical seal design protects the springs within the mechanical seal from the fluids being pumped.

The second design feature and open secret of Chesterton’s mechanical seal design is balance. On the mechanical seal, there are two main sides, the fluid side, and the atmospheric side. To prevent moisture from leaking out of the seal, both sides put equal pressure on each other to trap the fluid. Many seals will often see that the fluid side exerts greater pressure than the atmospheric side. Not only does this reduce the quality of the seal, but it can also ruin the pump with time. Balanced seals reduce the seal ring area on which the hydraulic pressure of the liquid in the pump acts. This allows for better lubrication that results in lower heat generation, face wear, and power consumption. Balanced seals will generally have higher pressure ratings than unbalanced seals.

Fretting on a pump shaft refers to the way that a material is worn away on a shaft by an elastomeric material. An example may be a 316 stainless steel shaft sleeve that is damaged by a Viton O-ring. Stainless steel protects a shaft from corrosion by forming a chrome oxide layer on the surface.  The dynamic O-ring wears that protective surface away and it then reforms.  Over time the chrome oxide gets imbedded into the O-ring and works like sandpaper removing even more material.  The result is a groove worn into your expensive sleeve and a leaking mechanical seal. Chesterton seals utilize designs that have any dynamic O-rings operating against a non-metallic surface, usually the sacrificial face.

Additionally, some manufacturers offer seals that are self-fretting, rather than shaft-fretting. What this means is that these seals do not fret or damage the shaft, they harm seal itself. While this protects the pumps, the O-rings still work against metal, reducing the lifespan of the seal itself.

Some mechanical seal designs utilize an inserted seal face, typically made of carbon or graphite inserted into a metal holder. However, the disadvantage to this technique is these non-metallic materials often react to heat differently than the metal of the seal. The result is the face of the seal is easily deformed- leading to leaks and early replacement of the seal. Proper mechanical seal design uses monolithic seal faces without using a holder and inserted face. By using Finite Element Analysis (computer modeling), Chesterton’s monolithic seal face designs are made more efficiently than ever.

Mechanical seals can either use rotating or stationary springs. With rotary mechanical seals, it is important that the stuffing box face is perpendicular to the shaft for the faces to stay closed. There will always be some resulting misalignment from installation and parts tolerances so this alignment cannot be assured. To compensate for the misalignment, the springs must adjust each time the shaft rotates to keep the seal faces closed. At motor speeds this adjustment happens thousands of times per minute (for 1800 rpm, 3600 adjustments occur) which is not only difficult to accomplish, the springs will fatigue and fail causing seal failure.  Rotary seals are simple in design which makes them inexpensive

In contrast, a stationary seal is designed in such a way that the springs do not rotate with the pump shaft; they remain stationary. Because the springs do not rotate, they are unaffected by the rotation of the shaft or how fast the shaft rotates. The springs do not need to correct or adjust with each rotation; they adjust for misalignment only once when installed. Chesterton uses this as the fifth design requirement, and this provides greater life to their mechanical seals.

Using these five design principles, Chesterton has updated its 150 seals to the new 1510 seal. The new design uses a monolithic seal face and changes where the dynamic O-rings are placed to be a non-fretting seal. Chesterton unveiled this updated seal in the US in September of 2022. However, Chesterton also has one additional add-on for this new seal. Starting at the end of October 2022, Chesterton will be releasing the 1510L. The 1510L has all the same design capabilities of the 1510, the difference between the two is the installation process. The 1510L utilizes a lock ring mechanism to simplify installation requiring the installer to tighten only one screw to connect the seal to the shaft.

To request a demonstration for the 1510L mechanical seal, click here. Learn more about Northwest Pump’s mechanical seals by contacting us here, emailing us at sales@nwpump.com, or by calling 1-800-452-PUMP.

For service on your mechanical seals by our Chesterton certified pump technicians, contact us here, email us at service@nwpump.com, or call 1-866-577-2755.