Catalog: Precision Rolling Bearings | |
| precision rolling bearings page technical data contents 1 ... classification of precision rolling bearings for machine tools q main spindle ... bearings w ball screw support bearings 2 4 2 4 15 5 7 11 14 21 16 20 21 26 22 ... 32 33 37 38 47 40 41 47 53 48 48 50 1 2 bearing selection and shaft housing design q ... bearing selection w bearing accuracy e bearings and rigidity r designing bearing and ... housing 5 3 load rating and life q bearing life w static load rating and allowable ... axial load 16 4 allowable speed 5 bearing arrangements and structures of bearings ... for main spindles qwerqwertyuio bearing arrangement for main spindles bearing ... selection based on bearing arrangement for main spindle adjustable ... preload bearing unit bearing jacket cooling system 22 6 handling of ... | |
| 1 classification of precision rolling bearings for machine tools 1 main spindle ... bearings table .1 types of precision rolling ... bearings for machine tools bearing type standard cross section bearing ... u 72c high-speed 2la-hse9 5s-2la-hse9 bearing bore mm contact angle remarks ¡a ... bearing type code containing a suffix u means ... an ultage series bearing optimized interior structure and resin ... with bore diameter of 10 to 130 mm ¡bearings with prefix 5s have ceramic balls ¡ ... higher speed rigidity and reliability ¡bearings with prefix 5s have ceramic balls ¡ ... higher speed and limited heat buildup ¡bearings with prefix 5s have ceramic balls ¡ ... ultage series ¡these bearings are identical to the hse and hsf types ... and reduce energy consumption ¡bearings with prefix 5s have ceramic balls ¡ ... | |
| technical data bearing type standard cross section bearing ... type bearing bore mm contact angle remarks ¡the ... highspeed single-row cylindrical roller bearing are the same as those of the n10k only ... the bearing clearance is non-interchangeable ¡a ceramic- ... high-speed cylindrical roller bearing n10hsk ¡ultage series ¡this is a ... -friendly single-row cylindrical roller bearing 240 241 n10hsl k 55 100 plug gage ta 30 ... n10-hsk single-row cylindrical roller bearing and nn30k double-row cylindrical roller ... bearing 242 plug gage ring gage ring gage tb ... taper gage sb clearance adjustment gauge 35 160 ¡clearance gage ... n10-hsrk single-row cylindrical roller bearing and nn30k nn30hsk double-row ... cylindrical roller bearing 243 adjustable preload bearing unit ... | |
| technical data 2 ball screw support bearings bearing type cross section bearing type ... -contact angular contact thrust ball bearing for ball screws sealed type bearing ... ¡surface modification treatment on the bearing ring raceways has led to a longer ... bearing life and much improved fretting ... grease the sealed type boasts a longer bearing life and simpler maintenance work ¡all ... 40 30 ¡the allowable axial load of this bearing type is greater owing to the improved ... design 292 293 angular contact ball bearing for ball screws ¡a clearance remains ... between the inner ring of radial bearing and the inner rings of both thrust ... bearings allowing the user to determine the ... based on the starting torque ¡the bearing clearance on certain preloaded bearings ... | |
| technical data 2 bearing selection and shaft housing design 1 ... bearing selection generally the optimal bearing must be selected to suit the nature of ... the machine the spindle specification bearing type lubrication system and drive ... rigidity and critical speed etc of the bearing table 2.1 summarizes a typical bearing ... made to select an optimal main spindle bearing for a machine tool table 2.1 bearing ... and construction of components to house bearings ¡bearing mounting location ¡dimensional ... limitations ¡magnitude and direction of bearing load ¡magnitude of vibration and shock ... load ¡shaft speed ¡bearing arrangement fixed side floating side ¡ ... design life of components to house bearings ¡dynamic/static equivalent load ... method ¡noise and torque of the bearing ¡bearing operating temperature range ¡ ... | |
| technical data table 2.2 bearing selection procedure user s requirements ... main spindle size lubrication system ng bearing size consideration of allowable dmn ... drive-up of front cover estimation of bearing internal preload at maximum speed and ... consideration of bearing initial clearance according to ntn s bearing selection ... guideline finalization of bearing specifications consideration of ... rigidity of bearing and main spindle consideration of ... bearing life ok finalization of main spindle ... in selecting an optimal main spindle bearing for machine tool are summarized in ... 2.3 table 2.3 selection procedure for bearings for main spindles of machine tools 1 ... etc #30 #40 #50 etc d1 d2 d3 d4 bearing type/bearing number fr1 fr 4 shape and ... -related dimensions example 5 intended bearing type bearing size and preloading method ... | |
| and housing depending on the fit of a bearing to a shaft and a housing the bearing ... internal clearance can vary for this reason an adequate ... bearing fit has to be attained so that the ... bearing can perform as designed refer to the ... also the axial tightening torque on a bearing needs to be considered to avoid ... deformation of bearing raceway surface owing to axial ... tightening of the bearing it is necessary to carefully determine ... and the number of tightening bolts the clearance on a tapered bore cylindrical roller ... bearing is adjusted by changing the drive-up to ... associated with an appropriate fit of a bearing to a shaft and/or a housing are the ... with iso r1101 2 the length of the bearing fit surface is often too small to ... for example when a jis class 5 bearing is used for a housing with a 50 mm ... | |
| low speed heavy loading etc ball bearings roller bearings 2 1 0.5 3 1.5 1 4 ... load can be exerted on a main spindle bearing on a machine tool allowing for tool ... stationary when an angular contact ball bearing is subjected to a larger axial load the ... the allowable axial load for each bearing is found in the associated dimensions ... table high bearing speed leads to high temperature rise on ... the bearing owing to frictional heating within the ... bearing when the temperature of the bearing exceeds a particular limit the ... significantly possibly leading to bearing overheating or seizure the factors that ... can affect the maximum allowable bearing speed include 1 bearing type 2 bearing ... jet lubrication etc 4 internal clearance or preload on the bearing 5 bearing ... | |
| technical data 3 adjustable preload bearing unit a recent trend in the machine tool ... rigidity therefore main spindle bearings must be capable of both high-speed ... of the unit the ntn adjustable preload bearing unit is a highspeed high-rigidity unit ... conditions the ntn adjustable preload bearing unit is illustrated in fig 5.1 ... preload sleeve situated in the rear bearing section of the unit this changes the ... preload on the bearings a spindle incorporating a 3-step ... adjustable preload bearing unit is illustrated in fig 5.2 the ... can move smoothly angular contact ball bearing with ceramic balls adjustable preload ... unit work piece side locating side bearing preload adjustment side bearing drive ... side angular contact ball main spindle bearing with ceramic balls bearing box fig 5.1 ... | |
| technical data 4 bearing jacket cooling system with a built-in ... heat generated by the motor affects the bearing overheating of the bearing as well as ... about cooling of jacket a typical bearing arrangement is shown in fig 5.4 and 5.5 ... a double-row cylindrical roller bearing and an angular contact ball bearing set ... an area above the angular contact ball bearings and does not cool the double-row ... cylindrical roller bearing effectively note that the fit of the ... angular contact ball bearings with the bore of the housing is a ... clearance fit-the bearings are not in direct contact with the ... above the double-row cylindrical roller bearing and cools both the angular contact ball ... bearings and the double-row cylindrical roller ... bearing effectively in out cooling groove on ... | |
| 1.05 4d d 5 b d0 2 mounting by heating bearings when mounting a bearing to a shaft ... using a constant temperature chamber bearing heater or the like follow the ... instructions below heat the bearing at a temperature that reflects the ... temperature t 23.8°c therefore the bearing should be heated to approximately room ... lower-temperature shaft will cool the bearing causing it to shrink consequently the ... bearing may need to be heated by more than 30°c ... for the cage of angular contact ball bearing do not excessively heat the bearing ... 80°c max ¡as a result of heating bearings after cooling the inner ring will ... axially shrink and there will be clearance between the bearing side face and shaft ... fig 6.6 for this reason keep the bearing and shaft forced together with a press ... | |
| by table 6.2 nut tightening force bearing bore diameter nut tightening force ... tightening force when incorporating a bearing into a main spindle the bearing must be ... and maintained with a predetermined bearing pressure in order to maintain ... appropriate accuracies clearances and rigidities of the bearing and main ... locating a duplex angular contact ball bearing by using a bearing spacer the cross- ... depending on the tightening force the bearing pressure and elastic deformation by ... when securing an angular contact ball bearing onto a main spindle the bearing inner ... by the shoulder of main spindle and a bearing nut and/or stepped sleeve this inner ... the axial direction varying the axial clearance on the bearing in the case of a back-to ... -back duplex bearing db dtbt or dbt for a main spindle in ... | |
| technical data 7 clearance adjustment for cylindrical roller ... bearing when incorporating a cylindrical roller ... bearing into a main spindle of a machine tool ... center and setting the internal clearance to zero or to a negative clearance the ... inner ring of the bearing usually has a tapered bore the internal ... clearance is adjusted by fitting the tapered bore ... bearing onto the tapered portion of the main ... spindle and driving the bearing in the axial direction to expand the ... inner ring for adjusting the internal clearance two methods are available a method ... consisting of clearance measurement for each bearing and ... a method with a post-mounting internal clearance adjustment gage ex 2 housing outside ... 150/200 2 0.0015 6.11 2 measurement of bearing position and bearing radial clearance ... | |
| 101.54717 if the targeted post-mounting clearance value 0.015 l1 15 dm dia 60 1 0. ... .7705 measurement with mounted internal clearance gage the mounted internal clearance ... used as a location for measurement the clearance at the location for measurement is ... as illustrated in fig 6.23 the clearance gage consists of a ring gage dial ... operation detach the fixture 4 bearing clearance measurement after insertion of spacer ... the spacer does not move next move the bearing outer ring up and down by hand and ... measure the internal clearance after mounting post-mounting internal ... clearance rn the estimated bearing clearance n after press-fitting of the outer ring ... various components on mounted internal clearance measurement gage 5 final adjustment for ... ln so as to adjust the postmounting bearing clearance to the targeted clearance ¡by ... | |
| data 2 setup of mounted internal clearance gage ¡place the cylinder gage onto the ... bore surface of clearance adjustment gage as shown in photo 6.5 ... difference between the reading on the bearing and the reading on the cylinder gage ... on dial 2 coincides with the zero bearing clearance the distance between the ... 6.5 3 setting up the mounted internal clearance gage on the main spindle ¡mount the ... main spindle and lightly tighten the bearing nut ¡tightening the open/close bolt see ... fig 6.23 on the clearance adjustment gage will cause the gage ... in the inner ring ¡lightly swing the clearance adjustment gage in the circumferential ... dial indicator 4 setup of inner ring clearance ¡tighten the shaft nut of the main ... until the reading on the dial of the clearance adjustment gage becomes zero ¡once the ... | |
| steps 3 setting up the mounted internal clearance gage on the main spindle and 4 setup of ... inner ring clearance check the mounted roller outside ... diameter and the clearance setting note this process is only a re- ... procedure and may be omitted once the clearance measurements fall in a smaller range ¡ ... 6.26 the value of the mounted internal clearance is 1/2.5 times as large as the ... in fig 6.26 5.0 remaining internal clearance 5.0/2.5 2 m setup of mounted ... internal clearance clearance indication factor and mounted internal ... clearance reading 1 clearance indication factor because of the ... structure of the ntn mounted internal clearance adjustment gage the ratio of the ... clearance reading on location for measurement to ... the reading on dial indicator is 1:2.5 clearance indication factor the clearance ... | |
| 9 running-in operation for main spindle bearings run-in is important for ensuring smooth ... of grease-lubricated main spindle bearings the following two modes of running-in ... are recommended 1 the bearing speed is gradually increased in steps ... to the next step fig 6.34 2 the bearing is run for several minutes up to about ... maximum allowable speed limit of the bearing this cycle is repeated two to three ... phase involves a steep increase in bearing temperature possibly deteriorating the ... the temperature of a main spindle bearing is measured on the front cover the ... temperature difference across the bearing outer ring and front cover reaches 2 to ... running-in operation is restarted 40 35 bearing mounted preload jacket cooling 5s- ... 25 4000 0 0 1 2 3 4 5 6 7 8 20 time bearing mounted preload jacket cooling 60 50 h ... | |
| ntn main spindle bearings main spindle bearings 9 angular contact ball bearings for ... loads contents 9 angular contact ball bearings for radial loads 56 213 q features of ... types 56 w standard cage design 58 e bearing designations 58 r bearing accuracy 60 t ... internal clearance and standard preload of duplex angular ... contact ball bearings 62 y recommended fit for angular ... contact ball bearings 68 u duplex angular contact ball ... bearings 68 i duplex arrangement codes of duplex ... angular contact ball bearings 69 o flush grinding and universal ... matching 69 !0 angular contact ball bearings with ceramic balls 70 !1 operating life ... of bearings with ceramic balls 71 !2 recommended ... 72 !3 standard angular contact ball bearings 79u and 70u types 73 !4 high-speed ... | |
| ntn main spindle bearings 2 standard cage design table 9.1 ... standard cages of angular contact ball bearings for radial loads bearing series 78c 79u ... information contact ntn engineering 3 bearing designations 78 79 70 72 bnt type 5s 7 ... p4 jis class 4 p2 jis class 2 internal clearance code gl light preload gn normal preload ... gxx special preload csxx special clearance matching code db back-to-back double- ... angle code c 15° ad 25° no symbol 20° bearing series ultage series bore diameter code ... dimension table dimension series code bearing type material code 5s ceramic rolling ... | |
| ntn main spindle bearings 5 internal clearance and standard preload of duplex angular ... contact ball bearings the initial internal clearance or ... preload for duplex angular contact ball bearings is determined with consideration for ... or during operation the internal clearance of the bearing may be significantly ... due to three factors the reduction in clearance caused by fits the temperature ... force depending on the initial internal clearance a significantly reduced clearance may ... determine the optimal initial internal clearance and initial preload required for ... using a duplex angular contact ball bearing on the main spindle of a machine tool ... gn light preload gl 0 to positive clearance for duplex angular contact ball ... bearings ntn recommends the initial radial ... | |
| ntn main spindle bearings 6 recommended fit for angular contact ... ball bearings if the dmn value is in the range of dmn ... to ensure high accuracies of precision bearings if the dmn value is in the range of dmn ... 7 duplex angular contact ball bearings duplex angular contact ball bearings ... combined in rows of two three or four bearings to accommodate required specifications ... load and large axial load but this bearing can take the axial load in one ... for this reason this type of duplex bearing is commonly used for the main spindles ... each duplex angular contact ball bearing is manufactured as a set to enable ... adjustment of the preload and clearance for this reason combine only duplex ... bearings of the same product number table 9.20 ... 315 unit fit of outer ring with housing bearing on fixed side bearing on free side 2l ... | |
| ntn main spindle bearings 8 duplex arrangement codes for angular ... contact ball bearings each duplex ball bearing has a product number and duplex ... its side face on angular contact ball bearing sets of three or more each matching ... bearing has a mark on its outside surface ... align the mark when assembling the bearings note that duplex angular contact ball ... bearing types db and df do not have the mark ... universal matching angular contact ball bearings are often combined for a special ... rows of two or more when combining many bearings it is important to control the ... accuracies of the bearings and to align their face heights in a ... alignment can ensure the specified clearance and preload for df db and dt sets but ... it is possible only if the combined bearings have the same clearance/preload symbols ... | |
| ntn main spindle bearings main spindle bearings 10 cylindrical roller bearings contents ... 10 cylindrical roller bearings q double-row cylindrical roller ... bearings w single-row cylindrical roller ... bearings e bearing designations r accuracy of tapered bore ... t accuracy of cylindrical roller bearings y radial internal clearance of ... cylindrical roller bearings u recommended fit of high-precision ... cylindrical roller bearings i recommended lubrication ... speed double row cylindrical roller bearings 216 243 216 216 217 217 218 220 222 223 ... -speed single row cylindrical roller bearings n10hsrt6 type !1 eco-friendly air-oil ... speed single row cylindrical roller bearings n10hslt6 type !2 dimension tables for ... cylindrical roller bearings double-row cylindrical roller bearings ... | |
| ntn main spindle bearings 10 cylindrical roller bearings in a ... cylindrical roller bearing the rollers and raceways are in linear ... contact consequently this type of bearing can support a larger radial load than a ... point-contact ball bearing also its structure is suitable for high ... -speed operation a cylindrical roller bearing used for the main spindle of a machine ... a tapered bore so the radial internal clearance can be adjusted 2 single-row ... cylindrical roller bearings single-row cylindrical roller bearings ... highspeed n10hsrt6 type the n10hs type bearings have high-strength machined brass cages ... while the n10hsr type bearings have special molded resin cages which ... from the high-speed n10hsrt6 type bearing and can be used with air-oil ... only 1 double-row cylindrical roller bearings double-row cylindrical roller bearings ... | |
| ntn main spindle bearings 3 bearing designations nn49 30 nnu49 type nn 30 ... 4 up special high precision internal clearance code see table 10.4 10.6 external ... specification dimension series code bearing type code nn double row with ribbed ... hsr ultra high speed specification bearing type code n single row with ribbed ... main spindle refer to 6 handling of bearings 8tapered bore cylindrical roller ... bearing and main spindle taper angle in the ... table 10.1 tolerance of taper-bored bearings unit d over 18 30 50 80 120 180 250 315 ... | |
| ntn main spindle bearings 6 radial internal clearance of ... cylindrical roller bearings non-interchangeable radial internal ... clearance two types of radial internal clearance are available non-interchangeable ... radial internal clearance for which the combination of outer ring ... and interchangeable radial internal clearance that allows for different outer ring ... and inner ring combination the clearances listed are common to both double-row ... roller table 10.4 cylindrical bore bearings nominal bore diameter cylindrical bore ... bearing 1 bearings for machine components including ... highprecision machine tool main spindle bearings with noninterchangeable radial internal ... clearance and a small clearance range are used if a double-low tapered ... bore bearing is used and the desired mounted ... | |
| ntn main spindle bearings interchangeable radial internal ... clearance cylindrical bore table 10.6 nominal ... 260 275 305 370 410 440 adjustment of clearance in tapered bore bearings mounted ... internal clearance of a tapered bore bearing can be adjusted by controlling the ... with using a mounted internal clearance gauge the clearance gauge is convenient ... mass-production refer to 6 handling of bearings 7 clearance adjustment for cylindrical ... roller bearing measurement with mounted internal ... clearance gage in the technical data section 221 ... | |
| ntn main spindle bearings high speed test dmn value of 1.0 ... design fig 10.5 10.6 test conditions bearing speed mounted radial clearance ... lubrication mp-1 yes test conditions bearing speed mounted radial clearance ... 37 8000 min-1 speed 5 m mounted radial clearance grease lubrication lubrication mp-1 ... grease type yes jacket cooling bearing 1500h more than 5 times duration h fig ... | |
| ntn main spindle bearings high-speed operation test with grease ... .6 10.7 10.8 10.9 test conditions test bearing shaft speed mounted radial clearance ... -1 0 m grease no test conditions test bearing shaft speed mounted radial clearance ... outer case cooling test conditions test bearing shaft speed mounted radial clearance ... 5 min 40 nl/min no test conditions test bearing shaft speed mounted radial clearance ... | |
| ntn main spindle bearings !1 eco-friendly air-oil lubricated ... cylindrical roller bearings the eco-friendly air-oil lubricated ... technology to the proven n10hsrt6 type bearing design the n10hslt6 type boasts limited ... speed machining operation n10hslt6 type bearing specification air-oil air-oil eco- ... oil consumption n10hs type conventional bearing type ultage n10hslt6 type note the ... spacer with the eco-friendly nozzle the bearing type code n10hslt6 represents the ... bearing proper while a spacer code stands for ... built-in nozzle for more details see 3 bearing designations fig 10.10 n10hslt6 type ... notes permissible speed of each bearing dmn value varies depending on the ... of the machine for which the bearing is used motor drive system cooling ... system and construction around the bearing consider the optimal choice referring ... | |
| main spindle bearings !3 taper gage and internal clearance ... for ntn precision cylindrical roller bearings as the need increases for machine tools ... precision is required of machine tool bearings for a precision bearing to exhibit its ... in particular when a tapered bore bearing is used the corresponding taper on the ... finished to the same precision as for bearings note that the contact area between ... gage remember that the radial internal clearance of a cylindrical roller bearing needs ... correctly adjusted too large a radial clearance can diminish the precision of the main ... spindle while too small a radial clearance can lead to abnormal heat generation ... and premature flaking of the bearing to ensure adequate internal clearance ... use a mounted internal clearance adjustment gage !4 dimension table for ... | |
| main spindle bearings !5 dimension table for mounted internal ... clearance adjustment gage part number applicable ... bearing boundary dimensions mm e d 101 107 114 ... | |
| ntn main spindle bearings 2 standard cage types table 11.2 ... standard cage of angular contact ball bearing for axial loads bearing series 5629 ... for details contact ntn engineering 3 bearing designations 562 0 20m gn p4 tolerance ... p5 ntn class 5 p4 ntn class 4 internal clearance code gn normal preload gm medium ... 103 mm bore dimension series code bearing type 5s hta 0 20 u a t2 db gl p4l ... tolerance for axial load internal clearance code gl light preload gn normal preload ... contact angle code no code 40° a 30° bearing series ultage nominal bore diameter see ... dimensions tables dimension series code bearing type material code 5s material of ... rolling element is ceramics no code bearing steel 249 ... | |
| ntn main spindle bearings 6 basic preload the initial internal ... clearance or initial preload must be selected ... | |
| ntn main spindle bearings 12 tapered roller bearings 2 bearing ... designations tapered roller bearings are designed so that the apexes of the ... are located at a common point on the bearing center line accordingly the rollers ... inner ring and outer ring raceways this bearing is suitable for handling a radial load ... in general the cage of a tapered roller bearing is a punched steel plate type if p4 or ... modification code nominal bore diameter bearing series code 1 load calculation tapered ... roller bearings are generally used in pairs so their ... according to table 12.1 table 12.1 bearing arrangement and equivalent load bearing ... y1 note 1 the above are valid when the bearing internal clearance and preload are zero ... | |
| ntn ball screw support bearings 4 bearing designations the part number for a ... ballscrew bearing consists of a type code dimension code ... diameter mm nominal bore diameter mm bearing type code heat treatment ht type axn ... p5 jis class 5 p4 jis class 4 internal clearance code gm medium preload gh heavy preload ... dimension tables dimension series code bearing type code axn 2052 p4 tolerance class ... bore diameter outside diameter mm bearing type code axn arn 286 ... | |
| ntn ball screw support bearings accuracy of axn and arn type table 13. ... 12 inner ring and outer ring nominal bearing bore dia d or nominal bearing outside ... deviation mean outside dia 2 deviation bearing height deviation unit outer ring ... for each type of ball screw support bearings are shown in the dimension tables the ... enhanced by tightening the thrust bearing rings to supply preload preloads and ... tables to help control basic preload a bearing that allows preset preload by ... tightening the bearing raceways to adjust the clearance a ... between the both thrust bearing rings and radial bearing rings fig 13. ... | |
| ball screw support bearings r1a ra da da basic load ratings dynamic ... 5 500 4 700 4 300 3 900 3 500 radial clearance m da min max min abutment and fillet ... | |
| ball screw support bearings r1a ra da da basic load ratings dynamic ... 3 100 2 900 2 700 2 600 2 500 radial clearance m da min max min abutment and fillet ... | |
| ntn products 5 radial internal clearance the radial clearance of ntn cam ... fw over 3 6 10 18 30 incl 6 10 18 30 50 clearance cn normal clearance min 3 5 5 10 10 max ... between the outside surface of bearing and track is also necessary failure to ... could lead to premature wear of the bearing example application of ntn cam ... | |
