Miniature profi le rail guides - SKF.com

1 Miniature profi le rail guidesThe SKF brand now stands for morethan ever before, and means more toyou as a valued SKF maintains its leadership as the hallmark of quality bearingsthroughout the world, new dimensionsin technical advances, product supportand services have evolved SKF into a truly solutions-oriented supplier, creating greater value for solutions encompass ways tobring greater productivity to customers,not only with breakthrough application-specific products, but also throughleading-edge design simulation toolsand consultancy services, plant assetefficiency maintenance programmes,and the industry s most advanced supply management techniques. The SKF brand still stands for the verybest in rolling bearings, but it nowstands for much the knowledge engineeringcompany3 Technical data4 Application examples5 Product features6 Accuracy7 Load carrying capacity8 Order designations9 Mounting details10 Lubrication11 Carriage dimensions12 Accessories12 rail dimensions13 LZM miniatures slides15 Special designs (customisation)Contents23 Technical dataIn response to the market trend forincreased performance with a mini-mum of mounting space, SKF hasextended its product range by a mi-niature profile rail close cooperation with nume-rous customers combined with SKF sexperience has resulted in a minia-ture rail guide design that sets newstandards.

2 SKF offers its customers an excellenttechnical advisory service on the spotas well as a vast modular range forthe performance increase of machi-nes and installations. In total SKF offers seven rail sizesand fourteen different types of car-riages. Miniature profile rails are universallyapplicable and preferably used in au-tomation technology, electronics pro-duction, medical engineering and thepneumatic industry (see Applicationexamples, page 4).Technical dataStructure:Four-point contact ball recircula-tion system with identical load angles and 2 ball recirculationpaths per carriage for unlimited stroke Range:Four different types (7, 9, 12, 15)comprising different widths andcarriage lengthsRail material:Stainless steel or equivalentCarriage material:Stainless steel or equivalentwith return zones of POMBall material:Stainless steel material:ElastolanTemperature range:from 20 C up to +80 CSpeed:up to 3 m/s :up to 80 :2 accuracy classes (P5, P1)Stiffness.

3 3 standard preload classes(T0, T1, T2)Types of rails, carriages and systemsSizeLLMHS_TALLMHS_LALLMWS_TALLMWS _LAStandardStandard, longWideWide, long7 RailLLMHR 7 LLMHR 7--CarrierLLMHC 7 TALLMHC 7 LA- -SystemLLMHS 7 TALLMHS 7 LA--9 RailLLMHR 9 LLMHR 9 LLMWR 9 LLMWR 9 CarrierLLMHC 9 TALLMHC 9 LALLMWC 9 TALLMWC 9 LASystemLLMHS 9 TALLMHS 9 LALLMWS 9 TALLMWS 9 LA12 RailLLMHR 12 LLMHR 12 LLMWR 12 LLMWR 12 CarrierLLMHC 12 TALLMHC 12 LALLMWC 12 TALLMWC 12 LASystemLLMHS 12 TALLMHS 12 LALLMWS 12 TALLMWS 12 LA15 RailLLMHR 15 LLMHR 15 LLMWR 15 LLMWR 15 CarrierLLMHC 15 TALLMHC 15 LALLMWC 15 TALLMWC 15 LASystemLLMHS 15 TALLMHS 15 LALLMWS 15 TALLMWS 15 LALLMWS .. TALLMWS .. LALLMHS .. LALLMHS .. TAApplication examples4 ElectronicsPCB drilling and routing machineA flat-format and weight-saving de-sign enables small machine dimen-sions.

4 High power density results inshorter processing technologyPick-and-place manipulatorsA low-mass guidance system coupledwith aluminium profiles permits fastersequences of motion and higher equipmentOptical instrumentsEase of movement and corrosion-resistant materials ensure reliabilityin everyday industryCompact piston rod cylinderHigh rigidity and load carrying capac-ity designed for long service life in"short stroke applications" (typical forpneumatic applications).5 Product featuresMaximum utilisation of mountingspaceThe compact design of the SKF min-iature profile rail guides permits maximum performance on a mini-mum of mounting space. Dimensionsand weights of machines and instal-lations can be further improved machinery perform-ance, maximum speeds and accel-erations under loads acting in all directions are possible.

5 This permitsmore efficient processes and the reduction of cycle than 90 years of SKF experi-ence with rolling bearing geometryguarantee long product life. Mainten-ance intervals are extended and theservice life of machines and installa-tions is use of stainless steel in combi-nation with plastic components makes these guides universally applicable. The reliability in applica-tion engineering is increased andrisks are rails are ground on all faces. Themaximum rail lengths per piece areshown in the table opposite. SKFsupplies the rails in lengths accordingto customer requirements. The dis-tance measurement E (see Illustra-tion page 11) is manufactured sym-metrically, depending on the raillength. Upon request, SKF can also supplyspecial rails to customer wide range of 14 different types ofcarriages, each available in threepreload classes and with a choicebetween sealed and open types, per-mits optimum system designs tail-ored to the respective and stiffnessThe determination of an appropriatepreload renders the Miniature profilerail guide suitable for widely varyingoperating conditions and changes thestiffness of the overall recommends clearance-freesystems (T0) for applications withconstant load and low friction.

6 Forapplications characterised by shockloads, vibration and alternating loadsor torques, it is advisable to select apreloaded system (T1) and a (T2)system should be chosen for hightorques and high designationMaximum rail lenght per piece*LLMHR 71 000 mmLLMHR 9 / LLMWR 91 000 mmLLMHR 12 / LLMWR 121 000 mmLLMHR 15 / LLMWR 151 000 mm*For rail length > 1 000 mm, please contact classCharacteristicsT0 ClearanceT1 Light clearance up to light preloadT2 Preloaded systemfurther preload classes upon requestAccuracy6 Distance tolerance1614121086420100 200300 400500 600700 800900 Running parallelism accuracy in operationP5P1( m) rail length (mm)Pa1000 Dimension tolerances H (mm)N (mm)P1 0,010 0,015P5 0,020 0,025 The tolerances apply over the entire guide length for any combination ofcarriage and tolerance for paired systems or carriages at identical railposition H (mm) N (mm)P10,0070,007P50,0150,015 The dimensions H and N relate to the ideal centre of the dimension is derived from the mean value of two measured pointswith identical centre tolerance of rail attachment holes0,3 F7 Load carrying capacityStatic load rating C0 The static load rating C0is the loadwhich corresponds to an arithmeticalHertzian Pressure of 4 200 MPabetween raceway and balls.

7 Thispressure produces a permanent de-formation of approximately 0,0001of the ball moments MA, MB, MC The permissible static moments cor-respond to a moment load that pro-duces the same permanent defor-mation as in the static load rating directionSKF Miniature profile rail guides aredesigned to accommodate loads in load rating CThe dynamic load rating C is theconstant load which gives a theoreti-cal system life of 100 000 m of trav-el with a certainty of 90 %.Life calculationThe life of a profile rail guide is de -fined as the total linear distance travelled before the appearance ofthe first signs of material fatigue onthe raceways or rolling in laboratory trials and inpractice it is found that the life of apparently similar rail guides undercompletely identical operating con-ditions can differ. Calculation of therequisite bearing size therefore requires a clear statistic definition ofthe term bearing life.

8 All referencesto dynamic load rating of profile railguides apply to the basic rating lifeas covered by the ISO definition, inwhich life is understood as that ope-rating period reached or exceeded by90 % of a large group of identical bearings. The SKF life calculation isbased on 100 000 metres of calculation models assumemerely 50 000 metres of travel. Insuch cases, the dynamic load ratingsmust be divided by a factor of 1,26to ensure comparability with the SKFvalues. Where the stroke length and fre-quency are constant it is often easierto calculate the basic rating life inhours of operation using the equation:Permissible operatingconditionsPermissible maximum loadDIN 636, Part 2, stipulates that thecalculation of bearing life is valid onlywhen the equivalent dynamic loadingof a profile rail guide does not exceed0,5 C.

9 Any higher loading leads to animbalance of stress distributionwhich can have a negative effect onbearing life. Where such conditionsprevail, the user should turn to SKFfor recommendations and advice onbearing life calculation. Requisite minimum loadIn order to assure slip-free runningof profile rail guides , they must besubjected to a certain minimum general guideline is a minimumvalue of P = 0,001 C. The minimumload is of special importance in pro-file rail guides which operate at highspeed or with high acceleration. Insuch cases, the inertia forces of theballs as well as the rolling friction inthe lubricant can have an adverse ef-fect on the rolling conditions in theguide and can lead to damaging slipconditions between the balls and =CP3L10= basic rating life, 105mC=dynamic load rating, NP=equivalent dynamic bearing load, N12L10 h=50 000 000s n 60L10 h= basic rating life, hours of operations=stroke, mmn=frequency of stroke, min-1(number of movements from one end position to the other end and back again)

10 CP312 Order designation8 The following designation system should be used for inquiries and end-stopSteel end-stopSingle rail systemParallel rail systemAccuracy classof the railRail track lengthClearanceLight clearance up to light preloadPreloaded systemNumber of carriagesCarriage without sealsCarriage with sealsStandard carriageLong carriageSize 7 Size 9 Size 12 Size 15 System (carriage and rail )CarriageRailStandard railWide railMiniature profile rail9 Mounting detailsThe illustration opposite shows theideal mounting arrangement for min-iature profile rail guides . Carriage and rail can be mounted at both sides, but their datum planes shouldbe on the same side of the system. To ensure a neat abutment to the adjacent edges, these should featurea relief opposite table shows the maxi-mum tightening torques for fixingbolts depending on the thread height deviation in transverse direction HaPermissible height deviation in longitudinal direction HbIdeal mountingarrangementThread sizeMaximum tightening torqueNcmM 232M 3110M 4260M 5510 Tightening torque of fixing boltsHa= A ZHa= permissible height deviation (mm)A=distance of rails (mm)Z=calculation factor T03,0 10-4T1/T21,5 10-4Hb= B 7 10-5Hb= permissible height deviation (mm)B=distance of carriages (mm)Lubrication10 The relubrication intervals depend onthe environmental conditions and themagnitude and type of load!