Most fillers are stable up to 400 c, so they do not restrict use in high temperatures. Labyrinth seals alabyrinth seal may be specified where the process to be sealed is at low to moderate pressures and relatively high leakage flows are tolerable. Lowfriction seals with skf wave lip design the seal types crw1, crwh1, crwa1 and crwha1 have an skf wave lip design to reduce friction and heat generation. Maintaining an accurate clearance during nominal and transient operation and providing effective damping is of key importance for seal designers. The design is noncontacting and does not wear the machinery shaft. Ptfe seals parker hannifin 8 prdifa technology division general information 1 when to use ptfe seals in the 1960s, the addition of fillers was found to improve a number of physical properties, particularly creep and wear rate. Advanced labyrinth seal design performance for high. Air compressors generally will always use a labyrinth seal. Aircraft cabin air and engine oil an engineering view pdf speech. Labyrinth seals are also found on pistons, which use them to store oil and seal against high pressure during compression and power strokes, as well as on other nonrotating shafts. The approach used in the unique designs for improving the efficiency of labyrinth seals involved increasing the internal cavity turbulence of the seal. When using this fit, it will be necessary to take care for additional fixing of the gmn labyrinth seal to the housing or shaft by using additional gluing.
Align the drain port at 6 oclock position and slide the seal onto the shaft uniformly pressing both stator and rotor in the equipment. The two pieces interlock to effectively seal out the majority of contaminants while holding in the lubricant. An extensive data base was accumulated from published and inhouse experimental results as the foundation for the development of a design model for labyrinth seals. Made from chestertons proprietary polymer material technology, the chesterton, patentpending polymer labyrinth seal pls is a noncontact bearing seal designed to provide protection for pumps, motors, gearboxes, and other rotating equipment in splash applications. Incorporates a gas type seal that effectively seals around the shaft to protect against static and dynamic liquid leakage. Labyrinth seals are constructed in multiple pieces. Analysis of labyrinth seal flow patterns to improve bulk flow. Isotech of illinois inc, usa a labyrinth seal that is designed to allow for radial, axial and angular misalignment of the shaft is described. Labyrinth seal preprocessor and postprocessor design and parametric study by rumeet pradeep mehta thesis submitted to the faculty of the virginia polytechnic institute and state university in. I have attached a copy of their analysis and results within this report. Labyrinth seals lip seal alternative page intro an effective alternative to lip seals, chesterton offers a unique polymerbased labyrinth seal design for use in splash applications for protection of pumps, gearboxes and other rotating equipment. The other piece, called the rotor, is attached to the shaft and rotates with the motion of the system. This differs from most traditional seals, which use a single lip in an attempt to seal an opening. Design optimization and verification skf can work with you to optimize current or new designs with proprietary 3d modeling software that can also be used as a virtual test rig to confirm the integrity of the design.
Find labyrinth seals and clearance seals on globalspec by specifications. Shape optimization of a labyrinth seal applying the simulated. These seals generally do not perform well at low operating speeds. Pdf the influence of labyrinth seal structure parameters and their interaction on the characteristics of leakage amount are numerically investigated. Therefore, this paper uses the quaternionquadratic regression orthogonal 12 implementation method and determines the variation range of four control parameters on the basis of the general principles of labyrinth seal design. The steel inner ring is first surrounded with molded aluminum. Various groups of labyrinth seals based on their design and arrangement on the blades tips and on the rotor, are discussed in 3, 4, 6. The aluminum seal is offered in all sizes according to ball bearing row 62.
Gmn labyrinth seal cf 60 and cf 619 for spindle bearings. An example of such a seal is sometimes found within an axles bearing to help prevent the leakage of the oil lubricating the bearing a labyrinth seal may be composed of many grooves that press tightly inside another axle, or inside a hole, so that the fluid has to pass through a. The labyrinth seal has a number of grooves which interlock with other grooves or teeth. Standard labyrinthstyle airgas and oil seals used with atmospheric air and lowpressure gases effectively confine air in the stage casings and. Keywords machine tool labyrinth seal spindle bearing shaft seal precision machine tool. The hybrid labyrinth seal incorporates a plain contact seal component to solve some standard labyrinth seal limitations. Stepped labyrinth seal cavity control volume mass fluxes stepped labyrinth seal cavity control volume shear stress forces stepped labyrinth seal cavity control volume momentum fluxes straight labyrinth seal, teeth on stator notation for leakage, pressure and velocity stepped labyrinth seal, teeth on stator notation for leakage, pressure and. In these applications, it is the long and difficult path and the formation of controlled fluid vortices plus some limited contactsealing action that creates the seal. Labyrinth seals lip seal alternative an effective alternative to lip seals, chesterton offers a unique polymerbased labyrinth seal design for use in splash applications for protection of pumps, gearboxes and other rotating equipment. For a more complete description of dry gas seal principles of operation, see shah 1988.
The labyrinth seal consists of one or more sharpedged ridges machined on the outside diameter of a rotating shaft or on the inside diameter of a sealing passage as shown in fig. Predicting leakage flow in labyrinth seals dates back to egli. Geometry of a stepped labyrinth seal configuration case 1. The effects of two seal design parameters, namely blade tooth thickness and blade profile, on labyrinth seal leakage, as well as the effect of operating a seal in an offcenter position, were. Outboard of the dry gas seal is a barrier seal, which separates the gas seal from the compressor shaft bearings fig.
Using a tortuous path, labyrinth seals reduce leakage by dissipating the fluids kinetic energy through viscous forces caused by the formation of vortices in each seal groove. Pdf labyrinth seal design optimization based on quadratic. Optimizing a helical groove seal with grooves on both the rotor and stator surfaces. They operate on the principle of positive clearance and do not rub on shafts or housing.
A labyrinth seal is a type of mechanical seal that provides a tortuous path to help prevent leakage. They consist of a stationary and a rotating ring and are made of engineering plastic. Rotor will stretch once installed on the shaft and create interfe. Labyrinth seals and clearance seals specifications. Analysis of labyrinth seal flow patterns to improve bulk. Of course the cf labyrinth seal also provides all general advantages of a non.
Intuitively, they do this by taking advantage of the resistance to fluid flow depending on not just the p. Labyrinth seal air leakage performance in current and advanced high pressure ratio gas turbines is directly related to the limitations of current available sealing. This is important for the design of high pressure compressors, where labyrinth damping is a. Mounting instructions for labyrinth seals gmn bearing usa. Labyrinth seal design optimization based on quadratic. Geometry of a labyrinth seal with a smooth land, case 2. These seals are more info not designed to seal pressure differentials or to seal against high fluid levels. Straight through triangular labyrinth seals are one of the most commonly used.
Users may specify a labyrinth seal because of favorable operating experience, cost, or a dislike of mechanical seals. These types of seals are used in a variety of settings, and can be used on objects which rotate and otherwise move. The labyrinth is a straight through design and a defined clearance on the shaft. Find out how your company can benefit from plm built on salesforce. Noncontact labyrinth seal assembly pdf free download. This noncontact seal has no wearing parts and eliminates fretting caused by conventional lip seals. Labyrinth seals are intended to prevent fluid liquid or gas flowing from one region to another, while not sealing off the passage entirely.
Labyrinth seals and clearance seals selection guide. Labyrinth seals have been designed in the past in a variety of different shapes with different leakage mass flow rates. A typical type of noncontacting seal is the labyrinth seal, where circumferential grooves are cut into the rotor, stator or both. When choosing labyrinth seals and clearance seals, the operating speed and temperature must be considered. Volume iii analytical and experimental development of a design model for labyrinth seals. In addition the new cf labyrinth seal is also offered in a different design for standard ball bearings made from aluminum. Labyrinth seal calculations labyrinth seal calculations iainuts mechanical op 8 jan 07 11. The influence of labyrinth seal structure parameters and their interaction on the characteristics of leakage amount are numerically investigated by conducting a quadratic regression orthogonal. The labtecta product range is an advanced labyrinth design that offers ingress protection of ip66 as standard and up to ip69k with the labtecta op. A second seal element is received within the second groove and the retention of each seal element, within 12 sealing technology a crosssectional view of a noncontact labyrinth seal assembly disposed on a shaft constructed in accordance with a preferred embodiment of patent wo20147963. Similarly, if the labyrinth chambers are correctly designed, any liquid that has escaped the main chamber becomes entrapped in a labyrinth chamber, where it. Labyrinth seal geometries linear seal with more chambers a, stepped design b and seal in application to gas turbines c, 2. One piece, known as the stator, is affixed to the machine and remains stationary.
Inboard of the dry gas seal is an inner labyrinth seal, which separates the process gas from the gas seal. If your design requires looser fitting of the seal due to ease of mounting you might use the tolerance h7. Labyrinth air seal labyrinth seal design options oil seal ingersoll rand offers a complete range of seal arrangements to meet the specific needs of your application. Cavity pressures, velocity and leakage computation in straight through or stepped labyrinth seals.
A labyrinth seal is a seal which creates a complicated path for liquids to pass through, making it challenging for liquids to cross the barrier created by the seal because they have difficulty making their way all the way through the labyrinth. Apr 08, 2020 in fact, movement can make the labyrinth seal even more effective, depending on the design. The labyrinth seal is a controlled leakage seal used to prevent highpressure gas leaking out of the case to the atmosphere and minimizes internal leakage. Saving fuel, reducing emissions for rail freight applications, the ecoturn seal offers an approximate 20 inchpound 2. Apr 30, 2015 therefore, an investigation was undertaken to design, fabricate and test several unique labyrinth seal concepts intended to decrease leakage through higher efficiency. C geometry of three canted knives with a smooth land case 3. Labyrinth seal design options oil seal ingersoll rand offers a complete range of seal arrangements to meet the specific needs of your application. The advance labyrinth design allows the bearing housing to breath out when the shaft is rotating but seals when the shaft stops. In short, the integrated lip seal contacts the shaft at lower speeds, and. Skf noncontact labyrinth seals provide an ideal solution. A labyrinth seal is a type of mechanical seal that provides a tortuous path to help prevent. Specifically, im looking for calculations that give me leakage rates given a.
The paper introduces a variety of carefully thoughtout labyrinth systems for practical application and the designer is supplied with detailed design directives. The dynamic stability of the machine is also improved by the seal. Labyrinth seal fda seals american high performance seals. Labyrinth seals, formerly named leidenfrost seals or mini mace, have a very specific manufacturing process that guarantees the identity of the inner and outer ring profiles to ensure they remain inseparable here are the steps taken to produce a labyrinth seal. Labyrinth seal calculations mechanical seal engineering. Cavity pressures, velocity and leakage computation in. Labyrinth seals use a noncontact seal design and are specifically designed to protect bearings from splashing water and other contaminants. Standard labyrinthstyle airgas and oil seals used with atmospheric air and lowpressure gases. Morrison annular seals are devices used in turbomachinery to avoid flow losses which reduce efficiency. Engineered polymer seals installation instructions 1 3 2 4 seal orientation and parts. Brush seals and labyrinth seals in gas turbine applications.
The seal is mounted in a ball joint assembly that is also free to move. Another form of labyrinth and clearance seals is a laminar sealing ring, which uses a series of flat metal washerlike rings of varying diameters to create a labyrinth seal. Labyrinth seal pumps acds labyrinth seal design is reliable and provides trouble free centrifugal pump operation eliminating the need for a traditional mechanical seal. Therefore, an investigation was undertaken to design, fabricate and test several unique labyrinth seal concepts intended to decrease leakage through higher efficiency. Engineered polymer seals installation instructions polymer. Engineering a better noncontact seal machine design.
Capable of excluding contamination as effectively as contact or lip seals, skf noncontact labyrinth seals also operate with little or no friction. The implementation of brush seals as an alternative to labyrinth seals in a gas turbine engine is outlined in this article. Labyrinth seals and clearance seals are minimumleakage seals that protect machine elements from contamination through a noncontact method. Im looking for a paper or design calculations for labyrinth seals used in liquid service. This catalog reflects the latest design features at the time of printing. Plant engineerings 2016 product of the year award in the fluid handling category. Apply a thin film of lubricant to the shaft and bore. The company reserves the right to change designs and specifications at any time. In this white paper, learn how you can configure freely without requiring any custom development, and quickly update configurations as your needs evolve. Skf the kno wledge engineering company s p e c i f i c a t i o n design and ed velo p ma nuf act ur e a n d t e s t i n s t a. Lip seal alternative to avoid fretting chesterton labyrinth. The sinusoidal form of the skf wave lip considerably extends the path on the counter surface and reduces the radial load against the shaft. Advanced labyrinth seal design performance for high pressure.
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