Taking fixed position bearing is by sheet lists tapered roller bearing (TRB, this sheet lists tapered roller bearing to be in normal turning be apart from main radial and axial load bear below operating mode) assist the composition that block annulus through careful design with, this assists the action that blocks annulus is to be in fan brake or start invert from time to tome axial force bears below the circumstance that force is apart from. This bearing can serve as contacted ball bearing at 4 o'clock (FPCBB) and bearing of roller of only kind cylinder (CRB) combination plan, perhaps contacted ball bearing at 4 o'clock (FPCBB) and the replacement scheme that biserial TRB sets program. The other bearing photograph that goes up with the axis intermediate at take-off of high speed of fan gear case with current application is compared, tiemuken the belt of the company locates bearing, will look from function, cost and efficiency, it is a kind of solution that can offer an alternative. Taking fixed position bearing is by sheet lists tapered roller bearing (TRB, this sheet lists tapered roller bearing to be in normal turning be apart from main radial and axial load bear below operating mode) assist the composition that block annulus through careful design with, this assists the action that blocks annulus is to be in fan brake or start invert from time to tome axial force bears below the circumstance that force is apart from. This bearing can serve as contacted ball bearing at 4 o'clock (FPCBB) and bearing of roller of only kind cylinder (CRB) combination plan, perhaps contacted ball bearing at 4 o'clock (FPCBB) and the replacement scheme that biserial TRB sets program. Take fixed position bearing to have place to need axial space the smaller, efficiency that improves take-off and improve the excellent performance such as whole take-off system. The take-off of gear case of applied current situation that two bearing arrange is in sometimes take-off or the fixed end of intermediate axis the FPCBB that a side often uses a floating NU CRB and an axial fixed position is combined (graph 1) . In this system, columnar roller bearing bears only radial load, and osculatory ball bearing bore at 4 o'clock total axial force. Pursue 1 current bearing forms a plan the 2 plan that showed another kind can replace FPCBB and CRB combination in fixed end, this plan introduces two single lines (likeness or different set) the bearing of TRB is arranged. What two bearing have enough volume can assure to bear the weight of when using this kind of design to be inside the limits of all operating mode below working requirement area, must throw very big energy to choose correct raceway included angle. Because design a characteristic to be point contact,bearing of graph 2 2TRB is arranged, so FPCBB basically is used bear the axial load on radial load and proper point of view. The bearing plan of the constant or constant change bears when suiting to be being used normally gear axial force that this is not a kind of ideal. In bear when action of pure axial load, the ball can be contacted with an angle and raceway and with this osculatory horn has roll, and the central string that winding bearing even at the same time rotates. Such games is caused slide tinily between ball and raceway, those who if the graph is shown 3 times,bring about is general those who say to be destroyed to be begun by the surface is small flake. And, the outer lane of these FPCBB ball bearing and bearing between must use special pine cooperate to deliver bearing in order to prevent any likely radial load to go up. The result that produces from this is, need add orgnaization to turn in order to prevent outer lane, add key seat on outer lane for example. This has not at below the belt that will discuss locates bearing place is used by bearing the method that blocks shoulder and clamp of end panel both sides. Although, the permutation that the graph shows 2 times used the design that does not have ball bearing, but the axial active force with still must consider to proper load distributings and maintain bearing of two tapered roller to have certain when the design. Using so on want special caution. Graph on 3 balls small the belt that those who flake new-style belt locates the characteristic graph of bearing is shown 4 times is a kind of model locates bearing is designed. In the graph 5 in, a belt locates bearing is secured to be in right end of the axis bears the radial that comes from gear and axial force, at the same time a NU CRB carries bearing installation to be in as float another side. Taking fixed position bearing is a kind of high-powered two-way bearing, can replace a plan the bearing combination of 1 medium CRB and FPCBB. Also be one kind can replace the fold that uses in a few designs to locate sheet arranges the bearing plan that tapered roller bearing is arranged or biserial 2TS-DM TRB forms. This kind of bearing is similar a sheet lists tapered roller bearing to add on outer lane block annulus additionally. Graph the belt of 4 typical structures locates bearing pursues 5 belts locate bearing forms a plan 6 showed if where to just support axial power twice up,taking fixed position bearing is. The main axial strength that as a result of the axial force of helical gear action showed to go up in bearing with thick arrowhead in the graph, this axial force appears in below torsion condition, occupy whole job to circulate 99% even much. Be in below torsion condition, tapered roller bearing undertakes propping up to compound load with raceway and the roller that have collective acme, make pure roll. What because be pure scroll,produce similar ball bearing without any opportunities so is tiny and slip. However, sporadical the breakdown of electrified wire netting or dynamo and the resonance in brake process can be in cutty time increases drive torque on immanent and opposite way and in the axial component that gear wheel produces on direction instead. Additional, below a few circumstances the dynamo can be regarded as motor drives roll of fan turbine low speed to be safeguarded in order to go to the lavatory. Another a few circumstances for instance when low wind speed, cut rate only. Axial power is supported on all less important way that these circumstances need to take fixed position bearing to indicate in fine arrowhead (see a picture 6) . The rib of the rib of the big, small end panel that the axial force of this less important direction passes roller, inner ring and outer lane will deliver. The main characteristic that brings fixed position bearing includes the following fields. (1) reduce axial space: Only kind bearing replaces two traditional bearing to arrange, can use narrower design to reduce the width of gear case housing and weight. (2) have very strong compatibility with existing design. (3) because take fixed position bearing to run from time to tome 360 ° bear the weight of area, have pair of very good heart character, assured to positional validity is contacted between gear thereby. (4) reduce systematic cost. (5) decrease pressure stress and add bearing life: Bearing bears the weight of in 360 ° the area is used, be in those who produce general power the contact of all roller inside torque limits is shown 7 times like the graph. (6) optimize raceway / roller contacts horn, this choice that contacts horn is the rate of the radial load that is based on by the influence of gear train all generation and axial force. Special attention wants when choosing to bearing: The inductive axial power that taking fixed position bearing to go up to be caused by radial load always should be less than gear to transfer the axial power that come over. Since be in working loop,the rate that the radial of bearing raises the axial power that returns force and gear is a constant, so the axial force of gear always is enough make bearing interior is contacted each other. Graph 8 belts locate the movement of bearing bears the weight of area (7) of the likelihood when any one aspect of the matter in the two end of outer lane can have smaller exterior flange to be assembled with preventing to be in install instead (graph 9) . Graph 9 belts are exterior bearing of fixed position flange (8) in-house when bearing is made windage already by accurate set, accordingly, do not need a hand completely when assemble to move set bearing. (9) the use that AGMA 6006 lists tapered roller bearing to be arranged in the across in fan gear case to sheet has certain restriction. The requirement controls the axial windage limits of bearing accurately, have proper locomotive windage in order to make sure its are below all locomotive load and temperature condition. Because secure the belt of end to locate the NU that carries with float CRB uses bearing together, so accurate when assemble hand is moved adjust did not need completely. (10) basis AGMA 6006, requirement fan reachs design life of 20 years, the stress of the biggest contact that allows below equivalent load is: High speed axis (HSS) should not exceed 1300MPa; Among high speed axis (the bearing of HS-INT) should not exceed 1650MPa. The analysis shows: Bear the weight of in 360 ° to the belt that radial load and axial force bear when area similarly hereinafter locates bearing, its contact stress to be less than 1300MPa (bear only quite with FPCBB bearing axial power is same) , smaller than using bear the weight of area and bear only the CRB of radial load is even small much (graph 10) . Graph 10 inner ring and roller / the design that the greatest stress between ball takes the structure of fixed position bearing and material to choose a standard to take fixed position bearing quite is, the cage of line of center of roller of a prep above, it and inner ring secure roller together. Another choice is, take fixed position bearing to also can use a cage under roller center line, it and outer lane secure roller together. Such structure can mix two to block annulus detachedly to be used together (see a picture 11) . The structure with what kind of first selection, rely on the installation flow of gear case and possible special use greatly, install bearing like heavy-duty intermediate axis upend the circumstance in. Graph the 11 areas that take two dissociable back-up ring locate bearing to high speed axis, often need to make check and be tearinged open often install. When the examination, along with of whole take-off component takes fixed position bearing one case likely by from bearing inside pull, be similar to the examination method that at present we use. The osculatory surface of fan gear case because tiny particle pollution can produce horniness small indentation, bring about inchoate destruction and exhaustion thereby, this is very common on the history. The circle that turns because of take-off counts opposite more, so the bearing above it gets more easily the attack of outside contaminant. Accordingly, to raise the dependability of take-off, take fixed position bearing to be able to use the bearing material a future life that fights foreign matter to produce, and ES300 coating is used on roller will raise its dependability to the greastest extent. Graph the 12 experimental data that showed such one a complete set of has statistical sense: After using ES300 coating, the life of bearing rose 4. 5 times. Graph 12 fatigue life check a result: Although the limitation that ES300 craft takes fixed position bearing takes fixed position bearing to suit high speed very much / the circumstance of small axial force, for example: Among the high speed axis of gear case and high speed axis, but it or the limitation with have certain restricted what go up in other circumstance to use. For love or money of this kind of bearing cannot bear the preload of bearing interior. Bearing is on the less important direction through blocking annulus the carrying capacity to axial load bears the weight of on the main way than passing raceway the capacity of axial force is small much. But, the carrying capacity on less important direction has approached the axial carrying capacity of NJ CRB very much, such axial carrying capacity has found its use in the other position on fan gear case. Interesting is, if very much two-way bearing takes fixed position bearing to had been used to be on the application of car and aviation industry, the carrying capacity that and showed them successfully goes up in less important direction. The model of the load of these application and speed can be built first-rately, so the biggest to architect of fan gear case challenge is whether the work evaluates the property that takes fixed position bearing to fall in all and foregone environment circularly. Finally, the application taking case that should have taking fixed position bearing checks, see it whether accord with traditional practice. But these general tests that just have to any designs. Excelsior pursuit is perfect when should contacting bearing of ball bearing and NU columnar roller to serve as combination of a bearing to find extensive use on take-off of fan high speed at 4 o'clock, the dependability of take-off bearing still makes the weak point that whole system designs. It is OK that the more appropriate bearing that the industry thinks existence is other is arranged use, if bearing of fixed two tapered roller is being favorred gradually now. Taking fixed position bearing also is a kind of secures end as take-off bearing that can be chosen. Compare two bearing, the narrower width that takes fixed position bearing can make design personnel to larger space will reduce the width of gear case and weight. Because use a bearing to replace two bearing, take look of fixed position bearing relatively the permutation of the tapered roller bearing that lists at two sheet are being used in fixed end can rise about 30%- - the efficiency of 50% . Because take fixed position bearing to be in all be below torsion in 360 ° bear the weight of the area works, so displacement quantity of the axis is met the smallest, and the problem of clench the teeth that the windage of bearing also won't cause gear wheel again, on the raceway that is not a contact the problem of existence stain also was done not have. Although be in,the applied watch palpability of a lot of respects takes fixed position bearing to have the experience of a lot of materiality, but the test that the spot confirms to its apply actually is very important still, because there is a lot of on fan application,quantified instantaneous state cannot have in design phase. So, the company is undertaking Tiemuken more detailed analysis and lab test, taking fixed position bearing in order to confirm is the best option that uses on axis of parallel of fan gear case. CNC Milling
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