Alibaba manufacturer directory suppliers, manufacturers. Curvic coupling, 2 the semiuniversal coupling, and 3 the releasing coupling or dutch, the. Nov 12, 2010 upon closer look the gap was just a slight chamfer on the back coupling. In a typical curvic coupling of a shaft, the teeth are generally located at the end faces of annular shafts, showing a hub andspoke pattern, as. The fixed curvic coupling is also sometimes referred to as a permanent curvic coupling due to. Design and production of a curvic coupling for testing purposes. Investigating curvic coupling behavior by utilizing the two and threedimensional. Arrow gear is a precision gear manufacturer, specializing in custom gearing and producing a wide variety of spiral bevel, straight bevel gears, stock gears, spur and helical gears as well as complete gearboxes. Curvic coupling, curvic coupling manufacturer in india. Size check select a gear coupling to connect a 500 hp, 1170 rpm electric motor to a drive high speed shaft of a maneuvering winch. Late in the day i did get a referall from the aerospace company to a smaller company. Bending and vibration of a discontinuous beam with a.
Flap the inboard and outboard tail rotor blades to gain visual access to the 429012120101 curvic coupling teeth. We are a custom gear facility, manufacturing gears to customer supplied blueprint specifications andor samples. Cad drawings available for over,000 standard parts in various 2d and 3d formats to fit most systems. You can chose from thousands of standard product options and the ability to customize for your needs whether youre looking for nonvalved. Gears, splines, curvic couplings equitable engineering. Frost angle setting technology fast in use on a curvic coupling. The coupling provides a positive drive along with precision centering and high load carrying capacity. Curvic coupling, hirth coupling manufacturers,curvic coupling. Our engineering staff can help with analysis of new designs as well as improvements on existing designs. Hirth joints consist of radial teeth formed by grooves milled or ground into the end face of. The stiffness and the accuracy of centering the coupling have become very important. Gleason model 887 cnc curvic coupling grinder with fanuc 18mb control.
Fixed curvic couplings the fixed curvic coupling is a precision face spline for joining two members, such as two sections of a shaft, to form a single operating unit. Request pdf a study on the cadcam of curvic couplings the curvic coupling was first developed by gleason works about sixty years ago. The stiffness of the curvic couplings is of guiding significance to the. Thanks to our accumulated experience and technical knowhow, we manufacture outstanding gears, cylinders, curviccouplings and reducers, which pave the way for a global manufacturer of machine tool parts. The three basic types of curvic couplings are the fixed curvic coupling, the semiuniversal coupling and the relating coupling. Rings with hirth couplings are primarily used for the accurate positioning of axialsymmetric components in the machine tool industry. Bending and vibration of a discontinuous beam with a curvic coupling under different axial forces show more 10. Submit any anomalies noted during inspection to product support engineering at. Schedule 40 longline coupling dia a b part number trade size carton qty. But moment is increased by the lack of bearing capacity of the curvic coupling. Both are the same diameter and have equal tooth geometry and tooth size. An accurate curvic stress determination early in the design process is required. Both haves are bottomed so the valleys will need work also. If the teeth of the 429012120101 curvic coupling were found improperly engaged per step 3, perform a rigging check of the directional control system.
The coupling shown in the diagram on the right above is suitable for use in cases subject to great radial loads. In order to manufacture the curvic coupling on a homemade cnc spiral bevel gear cutting or grinding machine, the manufacturing method for fixed curvic coupling was investigated. Buy best curvic coupling, hirth coupling with escrow buyer protection. A lecture on the method to compute the the stress of vtooth coupling under the actual operating conditions.
Curvic coupling, 2 the semiuniversal coupling, and 3 the releasing coupling or dutch, the coupling provides a positive drive along with precision centering and high load carrying capacity. Hirth couplings are also known as vtooth couplings, hirth joint, or voith hirth couplings. The method permits conversion of radial and axial runout measurements into part dimensions that represent manufacturing errors for each stage. The curvic coupling was first developed by gleason works about sixty years ago. Manufacturing method for fixed curvic coupling request pdf. You have clicked a page that seems to be very popular. The inspection of curvic coupling geometry is usually done by using a mating master curvic to check the transfer of a very thm coating of engineering blue. A new method is presented for optimizing the assembly of turbomachine rotors manufactured with gleason fixed curvic couplings. The arrangement needed to be easy to work with, so that during maintenance, the alignment could be easily reestablished. Panjiva uses over 30 international data sources to help you find qualified vendors of curvic. In order to ensure the coupling accuracy of aeroengines and gas turbines, curvic teeth and disk are usually formed integrally.
Digital inspection of fixed curvic coupling contact pattern bradley james nielson this report focuses on providing a foundation for further. The mating master curvic is also used to measure dimensions such as swash, radial runout and overall stacking height. Komet5 is used in bevel gear gearing and face type coupling production curvic couplings to calculate corrections for machine settings andor tool data in order to reduce variations between nominal and actual geometry. Although the stage 2 aft curvic is modeled, similar techniques may be applied to other curvic locations. Equitable engineering uses cadcam engineering to manufacture a wide variety of precision gears, splines, and curvic couplings. March 2000 machine was sent to gleason for full mechanical and electrical overhaulupgrade. Strength formula for curvic coupling division accuracy. Curvic couplingcurvic coupling is product description curvic coupling use for turret of cnc lathemachining center, robot, gas turbine, airplane, etc feature accurate and precise centering the curvature of the teeth give these couplings their very own and unique selfcentering feature. Hirth couplings hirth serration precision cnc machining. Skf cou plings cover a wide range of coupling types, sizes and capacity ratings for many applica tions and factory environments. This maintenance manual describes the correct service and repair procedures for all. Such failure would do harm to the structural integrity of curvic coupling and result in higher maintenance expense, costly downtime, and can be catastrophic in rotor. Then, it has been implemented through design and manufacture methods to be used for connecting shafts of gasturbine engine. Once program and dataspecific parameters have been configured, komet5 is a fully automatic, intuitive correction program.
I dont know how they ended up with a half of a curvic coupling set. In order to improve machining operation range, distance to the disk must increase as much as possible. Our mindset will be concentrated on satisfying the needs of our customers and working hard to become a futureoriented company. First introduced in 1942 by gleason works, a curvic is a precision ground face spline. Curvic couplings were first introduced in 1942 to meet the need for permanent couplings and releasing couplings clutches, requiring extreme accuracy and maximum load carrying capacity, together with a fast rate of production.
Curvic couplings are similar in concept and appearance to hirth couplings, except that. Using a bright light, inspect the inboard and outboard curvic coupling teeth for proper engagement with the inboard and outboard flapping bearing teeth. Grinding services including curvic coupling grinding services. Single reduction curvic coupling differential carriers. This design utilizes a single piece of material and becomes flexible by removal of material along a spiral path resulting in a curved flexible beam of helical. Our extensive machine center repair capabilities include id and od cylindrical grinding, wheel grinding, vertical grinding, plus. Stock spiral bevel gears a cost saving alternative. Like hirth couplings, they lock the components together in an unlockableremovable way and provide indexability. The curvature of the teeth give these couplings their. Finally, a computer program is developed for designing curvic couplings with design parameters as input variables to predict the contact patterns of designed curvic couplings and to. Find manufacturers and distributors of curvic couplings. Adaptation of these methods for use in estimating contact pattern between curvic couplings. As the coupling obtains a significant level of clamp force and hardness, it is optimally used for index tables at machining centers for heavy cuttings and in torque transfers.
The fixed curvic coupling is also used today by many. I have searched the internet and there is not much in the way of how to document them. Curvics are sometimes used in aircraft engine design where multiple rotor stacks are required. Nov 29, 2007 curvic coupling examples not having much experience with curvic couplings, is there anyone that would be willing to share a model and drawing of a curvic coupling style fixed curvic coupling. Investigating curvic coupling behavior by utilizing the. Their application makes it possible to fulfil an accurate centering, as well as an improved reliability and good structural stability.
To ensure stability in a threegroove kinematic coupling, the grooves must be arranged in a triangular fashion, such that the normals to the planes created by the two contact points of each coupling, intersect within the coupling triangle 9 as shown in figure 3. Fixed curvic couplings the fixed curvic coupling is a precision face spline for joining two members, such as two sections of a shaft, to form. Curvic coupling use for turret of cnc lathe machining center, robot, gas turbine, airplane, etc feature. Hirth couplings can also be used in a variety of different applications including fixture indexing, medical, coupling impellers, compressors to their driven turbine shaft, and many more. Minimizing assembly runout in turbomachines made with. We will lead this market at the head of this field.
Pdf a model accounting for stiffness weakening of curvic. Experts in hirth serrations, we offer a complete range of services to meet almost any requirements. Our main activity is the manufacturing of hirth couplings. It can result in a decrease in the structural stiffness or the separation of curvic coupling and lead to the joint failure. However the allowable load differs to the size of the curvic coupling in use. A hirth joint or hirth coupling is a type of mechanical connection named after its developer albert hirth. Dec 16, 2016 frost angle setting technology fast in use on a curvic coupling. Pdf curvic couplings are frequently used in aeroengine rotors.
Finally, a computer program is developed for designing curvic couplings with design parameters as input variables to predict the contact patterns of designed curvic couplings and to show them in the form of 3d models. Privy to only bits and pieces of the design details it was never any consideration of using anything other than a curvic even though the hirth coupling was brought up several times. Since then, our couplings have been widely accepted in japanese market under the bland name of formflex coupling and have acquired a high reputation. The jet engine industry needed an ultra precise locating arrangement to assure the exact alignment of components along the main engine shaft.
Curvic coupling is also sometimes referred to as a permanent curvic coupling due to its use in applications where the components being coupled are. For the purposes of this a d, access to the hp turbine rotor discs is defined as the removal of the hp turbine rotor assembly from the engine. Hirth couplings, also regarded as curvic couplings, are widely used for torque transmission between mating discs in turbine machinery and are not covered by international standards for instance iso, din or agma. The fixed curvic coupling is used extensively in the construction of builtup turbine and compressor rotors for aircraft and industrial gas or steam turbine engines. Industrial grinding services machine centers by repairing or rebuilding mating areas and worn diameters. Inspection of curvic couplings using a cmm wit press. Curvic manufacturers suppliers of curvic product and. Investigating curvic coupling behavior by utilizing two.
Buy best curvic coupling with escrow buyer protection. One half of the coupling is mounted on the turret mounting body. Analysis of the contact stresses in curvic couplings of. The most common method involves a curvic coupling mechanism.
It is used to connect two pieces of a shaft together and is characterized by tapered teeth that mesh together on the end faces of each half shaft. The three basic types of curvic couplings are i the fixed. Investigating curvic coupling behavior by utilizing two and. The single flexing coupling is for use in the case where shafts are supported by three bearings. A beam coupling, also known as helical coupling, is a flexible coupling for transmitting torque between two shafts while allowing for angular misalignment, parallel offset and even axial motion, of one shaft relative to the other. Th e serrated tooth circle divider uses two mat ing face gears. The fixed curvic coupling is used extensively in the construction of builtup. Precision passive alignment of wafers by alexis christian weber submitted to the department of mechanical engineering on february 20, 2002 in partial fulfillment of the. Dlc is a specialized manufacturer of curvic coupling such as curvic, index curvic coupling, turret curvic coupling, airplane curvic coupling, 2pieces curvic coupling, 3pieces curvic coupling. On british jet engines the hirth coupling fullfilled a similar roll to the curvic coupling, though all the ones i worked on had a supporting compressor shaft on which the compressor discs were mounted sliding fit with the hirth couplings transmitting the drive from disc to disc, and maintaining the correct spacing between the individual compressor discs which carried the aerofoil section. Digital inspection of fixed curvic coupling contact pattern. Curvic couplings are similar in concept and appearance to hirth couplings, except that their teeth are curved instead of straight. Threedimensional models were created in beasy and ansys, and are described in the following subsections. Hirth or curvic couplings, used in serrated tooth circle dividers, shown in figure 3.
Cpc couplings and fittings are ideal connectors for your plastic tubing applications in multiple industries, including medical, biopharmaceutical, chemical handling, liquid cooling of electronics, industrial, printing and food processing. A model accounting for stiffness weakening of curvic couplings. The inspection of curvic coupling geometry is usually done by using a mating master curvic to check the transfer of a very thm coating of engineering blue from the master to the curvic being inspected. These couplings, which provide optimum contact with the shaft, can accommodate high torque values. The fixed curvic coupling is used extensively in the con. Zn3r030m before the discs are eligible for reinstallation in an engine. A study on the stability of curvic coupling for distance.
We repair and rebuild machine components such as shafts, curvic coupling rings, spindle heads, and sleeves. Shaft collar, rigid coupling, flexible coupling cad files. Finally, a computer program is developed for designing curvic couplings with design parameters as input variables to predict the contact patterns of designed curvic couplings and to show them in. An investigation into using coordinate measuring machines cmms to measure gear geometry. Hirth coupling mechanical engineering general discussion. The present study, as a further evolution, proposes an experimentally validated closed form. Relying on our stateoftheart manufacturing set up, we are offering premium quality range of curvic coupling. Provided coupling is known for its accurate alignment and precision centering capability whenever it is in mesh. Curvic coupling of mill turret should maintain disk weight and the cutting resistance, which occurs when the machining operation must have a power transmission function. We provide prompt quotations, competitive pricing, and top quality gears. To connect the servomotor used in nc machine tools with the ball screw, an exceptional usage of the coupling as shown in the. The article curvic coupling design appeared in the novemberdecember 1986 issue of gear technology summary curvic couplings were first introduced in 1942 to meet the need for permanent couplings and releasing couplings clutches, requiring extreme accuracy and maximum load carrying capacity, together with a fast rate of production. Several bladeoff positions on each stage disk may develop the different characters on the contact pressure distributions of the curvic couplings during the application of a bladeoff load.
The curvics are used to couple multiple rotors in an aircraft engine compressor. Curvic coupling design novdec 1986 gear technology. A study on the cadcam of curvic couplings turbo expo. Pdf digital inspection of fixed curvic coupling contact pattern. A study on the cadcam of curvic couplings request pdf. Gear main product introduce bull gear marine engine gear pcc curvic coupling t curvic coupling seoam machinery industry we will make a great effort to satisfy customers with selfconfidence of the best.