Volume iii analytical and experimental development of a design model for labyrinth seals. Enthalpy entropy chart for fluid passing through a 18 labyrinth. These seals are more info not designed to seal pressure differentials or to seal against high fluid levels. The inner labyrinth seal actually consists of two separate sets of labyrinth teeth.
Leakage and cavity shape studies of labyrinth seals. The gas flow through the seals as well as its swirling oscillation within the cavities which are formed between the seal teeth can create a net pressure and shear forces that will act on the rotor. Since the seal material is flexible, the angled seal teeth deflect then return back to normal when the vibration level settles back to normal. Labyrinth seals use a noncontact seal design and are specifically designed to protect bearings from splashing water and other contaminants. The dynamic stability of the machine is also improved by the seal. 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. 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. Doublelip seals tsng doublelip seals are the most common seal design used with snt split plummer blocks.
Resilient metal seals meet the challenges of high temperatures or cryogenics, high pressures or hard vacuum, corrosive chemicals and even intense levels of radiation performing dependably year after year. The analytical model provided acceptable prediction in the case of straight seal, but did not provide satisfactory predictions for the stepped seal. This is important for the design of high pressure compressors, where labyrinth damping is a major contribution improving rotor stability. May 18, 2020 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. Counterbore for accurate positioning of seal eliminates possibility of cocking or skew positioning of seal chamfer bore for easy installation bearing shaft. Please see the comparison with standard contact seals in the table below. These documents are provided in both the pdf and html formats, download. They are used in many places in gas turbine engine to optimize and improve their design using cfd, is of interest to this study with newer designs of labyrinth seal. The two pieces interlock to effectively seal out the majority of contaminants while holding in the lubricant. Particularly annular seals are one of the most widely used in.
Polymer labyrinth seal unitized, noncontacting seal for bearing protection the chesterton patentpending polymer labyrinth seal pls is a noncontact bearing seal designed to provide protection for pumps, gearboxes, and other rotating equipment in splash applications. Certificate seal free vector art 8,239 free downloads. A theoretical model for the design of a labyrinth seal gland 46. 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. Pdf optimization of labyrinth seal for screw compressor. The seal itself as well as the specific design encompassing the seal satisfies only parts of the sealing requirement. Pdf the influence of labyrinth seal structure parameters and their interaction on the characteristics of leakage amount are numerically investigated. They stated that a straight seal with more teeth seems to be a suitable design. This way if oil escapes the first labyrinth of the oil seal, it is contained by the pressure of air coming from the outer cavity on the other side of the seal. Applicationspecific seal design american high performance.
Labyrinth seal design optimization based on quadratic regression orthogonal experiment article pdf available in energy and power engineering 0904. Morrison annular seals are devices used in turbomachinery to avoid flow losses which reduce efficiency. The steel inner ring is first surrounded with molded aluminum. Advanced labyrinth seal design performance for high pressure. The measurements have been carried out with and without a. Labyrinth seal is a noncontacting type seal that uses a tortuous path to minimize. Sealing of dry particles with greasefilled noncontacting. Geometry and fluid properties for conservation of mass 14 control volume of the ith seal chamber. Pdf design and development of a multipurpose test apparatus. Optimal seal performance depends upon proper selection for the process application, operating conditions, process gas composition, and design specifications. Intuitively, they do this by taking advantage of the resistance to fluid flow depending on not just the p. Cavity pressures, velocity and leakage computation in. Lehigh university lehigh preserve theses and dissertations 1994 cavity pressures, velocity and leakage computation in straight through or stepped labyrinth seals.
Control volume for conservation of momentum in tangential 16 direction. Seals are basic mechanical devices used in machinery to avoid undesired flow losses of working fluids. The other piece, called the rotor, is attached to the shaft and rotates with the motion of the system. Advanced labyrinth seal design performance for high pressure ratio gas turbines. The inboard set of teeth forms the seal balance labyrinth, which is subject to the high differential pressure explained previously. The ptfe lip seal design guide is your premier ptfe seal selection guide for hardware design, seal configuration and material specification options for a wide range of standard and complex applications. Incorporates a gas type seal that effectively seals around the shaft to protect against static and dynamic liquid leakage. The common name for the seal used in the cd on the leading edge as the paper approaches is the side seal.
Nov 22, 2011 an experiment using a fish tank and water to illustrate the difference between insulating your rv with fiberglass and insulating it with seal design s tounchn seal insulating foam. The parker metal seal the most extreme environments demand metal seal sealing solutions. In general, the disadvantage of such collections of different design examples is. Closed impeller with labyrinth seal at impeller eye. First measurements of labyrinth seals on a recently installed test rig. The company reserves the right to change designs and specifications at any time. An example of such a seal is sometimes found within an axles bearing to help prevent the leakage of the oil lubricating the bearing. These forces will contribute to the destabilization of rotors that are marginally stable, for a reliable design of the turbo machinery, it is.
With the aid of our sophisticated proprietary seal design software and 3d modeling software, we can design virtually any seal very quickly, thus reducing design and development cost. Labyrinth seals have been designed in the past in a variety of different shapes with different leakage mass flow rates. Abstract labyrinth seals are a noncontacting sealing device consists of a series of cavities connected by small clearances. Labyrinth seal air leakage performance in current and advanced high pressure ratio gas turbines is directly related to the limitations of current available sealing. 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 table on the following page compares the various features of each seal type. A theoretical model for the design of a labyrinth seal gland. May 04, 20 design, operation, and maintenance dresserrand. Conformance is verified by installing the labyrinth seal in an enclosed environment and subjecting the seal to a water spray from all practical directions. Pdf labyrinth seal design optimization based on quadratic. Because the seal is selfadjusting, the leakage path through the interface between the seal faces cannot be explicitly controlled although a controllable seal has been proposed and built salant and wolff, 1994, but can be minimized by proper design. Jul 05, 2016 labyrinth seals are intended to prevent fluid liquid or gas flowing from one region to another, while not sealing off the passage entirely.
Labyrinth seal design optimization based on quadratic. All of our design wax seal stamps come with the option to add a gift box, a stick of sealing wax, or both. Each seal type incorporates specific features to meet your application needs. Proper design and use of suction roll sealing strips in. The material being mixed is a blend of oil and detergents. Note the special use of shields and grease chambers.
The labyrinth seal is a special type of seal, used in screw compressors and turbomachinery for sealing purpose. Discrepancies are found when comparing theory with measured direct stiffness and the crosscoupling damping coefficients. Labyrinth seal pumps acds labyrinth seal design is reliable and provides trouble free centrifugal pump operation eliminating the need for a traditional mechanical seal. These types of seals are used in a variety of settings, and can be used on objects which rotate and. 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 long and.
Outboard of the dry gas seal is a barrier seal, which separates the gas seal from the compressor shaft bearings fig. One piece, known as the stator, is affixed to the machine and remains stationary. The suction roll seal typically consists of three primary components. Inboard of the dry gas seal is an inner labyrinth seal, which separates the process gas from the gas seal. When an abradable labyrinth seal was applied to a very large gas. Design tips illustrations numbered 6, 7 and 8 show several recom mended design tips for better application of trostel oil seals. Labyrinth seals are constructed in multiple pieces. This catalog reflects the latest design features at the time of printing.
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. Shape optimization of a labyrinth seal applying the simulated. The shaft may deflect during a vibration excursion, such as passing through a critical speed, and rub the seal. The seal is therefore named the axial labyrinth sealing system. Lip seal alternative to avoid fretting chesterton labyrinth. Choose from over a million free vectors, clipart graphics, vector art images, design templates, and illustrations created by artists worldwide. Timken snt split plummer blocks are available with multiple sealing options. The outboard set of labyrinth teeth forms the seal gas labyrinth, which is. Sort by featured best selling alphabetically, az alphabetically, za price, low to high price, high to low date, new to old date, old to new.
The trailing edge seal running parallel in the cd is typically the silencer seal. Rotating seal it is desired to seal a mixer shaft with a rotor extending into the vessel through a housing seal and bearing combination and driven at 450 linear feet per minute. The intelligent lip seal will include sensors, actuators and intelligent control, allowing. A labyrinth seal is a type of mechanical seal that provides a tortuous path to help prevent leakage. 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. Standard labyrinth style airgas and oil seals used with atmospheric air and lowpressure gases. 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. Reynolds number and rotation on these coefficients will result in the design of better performance seals. It is necessary to manufacture 14 fits to get a seal with only 3 labyrinth steps and very often the mounting space of custom made labyrinth seals is very large.