PRECISION BEARINGS FOR MACHINE TOOLS CUSCINETTI DI PRECISIONE PER MACCHINE UTENSILI

Specifiche tecniche Combined needle and roller bearings Indicazione per esecuzione parti adiacenti SRB Radial needle roller combined bearings with axial cylindrical roller Cuscinetti radiali a rullini combinati con assiali a rulli cilindrici Cuscinetti customizzati a rulli cilindrici incrociati TOLERANCES TABLES TABELLE TOLLERANZE n

Mondial is a leading company in thè import and distribution of por er transmis-sion components. Mondial always prò' ides its customers with highly qualified products matched with an excellent logistic and technical support. Mondial is an ISO 9001 certified Company. Mondial, Azienda leader nell'inr portazio-ne e commercializzazione di componenti meccanici innovativi e di elevata qualità, offre un servizio costantemente adeguato alle esigenze del mercato. Un servizio che integra dinamicamente l'organizzazione commerciale con quella tecnica e logistica, proponendo una completa gamma di organi di...

UNITEC, leading company in thè design and manufacturing of spec al precision cylindrical roller bearin foK machine tools and generai industry, delivers high quality Service and support to customers worldwide. Engineering partnership, technical and logistic Services and our commercial network, supplied by different distribution channels, allows us to fulfil unique application requirements on thè marketplace. UNITEC is a certified ISO 301 and ISO 14001 company, be. )ng ,ig to Mondial S.p.A. Group. Advanced technology to meet your customers requirements. Our engineers will assist you in selecting the...

RTB Combined axial-radial roller bearings for indexing tables Cuscinetti assiali-radiali a rulli per tavole di indexaggio TECHNICAL SPECIFICATIONS SPECIFICHE TECNICHE Axial-radial precision bearings for indexing tables. Due to their high axial stiffness and their capacity to bear high tilting moments, UNITEC bearings RTB series are particularly recommended for rotati’ j, pc sitioning and indexing tables and milling heads. 1. GENERAL DESCRIPTION RTB bearings consist of a L-shap- d inner ring - complet-ed with a washer, an outer rinr, twodfcllerthrust bearings and a cylindrical roller bear'ng,...

2. RIGIDEZZA Elevata rigidezza, grande capacità di carico, elevata precisione di rotazione, sono i requisiti fondamentali dei cuscinetti assiali – radiali UNITEC serie RTB. L’impiego di gabbie assiali ad elevato numero di corpi volventi con contatto lineare, oltre all’elevatissima precisione delle lavorazioni meccaniche, contribuisce ad ottenere un movimento preciso e rigido. Le dimensioni dei rulli, sia assiali che radiali, e degli anelli interno ed esterno sono calibrate in modo tale che al serraggio delle viti di fissaggio si ottengano i precarichi previsti.Le tolleranze, del valore del precarico...

RTB TECHNICAL SPECIFICATIONS SPECIFICHE TECNICHE Bearing assembled in housing and model for FEM analysis Schema di montaggio del cuscinetto e modello analisi FEM MOUNTING WITH THRUST WASHER (VSP) - MONTAGGIO CON RALLA DI SUPPORTO (VSP) In case a thrust washer is used in the assembly of the RTB bearing, the correct axial setting have to be evaluated. In this case, for any needed support, please contact our technical department. Nel caso di utilizzo della ralla di supporto, il cuscinetto RTB viene configurato a richiesta, valutando il corretto valore di registrazione assiale. Per ogni necessaria...

Stiffness values of rollino lements in preloaded con tions Rigidezze relative ai soli elementi volventi in condizioni di precarico teorico Stiffness values of a complete assembled hearing (°) Rigidezze relative al cuscinetto completo in condizioni di installazione di iferimento (°) (°) A.m. stiffness values consider the deformation of all components of the bearing and of the parts assembled with cap screws. Deviations from the actual values are possible according to the approximation of the model with respect to the real system. (1) The axial stiffness is calculated with the load applied top...

RTB TECHNICAL SPECIFICATIONS SPECIFICHE TECNICHE 3. ASSEMBLY INSTRUCTIONS As for assembly, we recommend to follow specifications indicated in figure 3.1. Usually, tolerances can lead to different mounting situations such as deflection or misalignments according to bore/outer diameter of bearings. WITH ROTATING INNER RING Rotating shaft We recommend a press fit of max 0,005 mm to impro ve accuracy and to limit friction torque. Housing We recommend to keep a small mounting clearance, except for applications demanding high precision in bearing adjustments. WITH ROTATING OUTER RING 3. INDICAZIONI...

Fig. 3.1 RTB assembly instructions Indicazioni di montaggio per RTB

RTBTECHNICAL SPECIFICATIONS SPECIFICHE TECNICHE 4. PRELOAD NOTION The preload of thè bearings increases thè stiffness and thè rotational accuracy. In presence of a load from thè outside, thè preload of thè hearing eliminates or avoids thè clearance corresponding to thè elastic yielding due to thè load itself. In this case, for a given range of loads, thè elastic deformations caused by thè load are smaller rather than in a non-preloaded hearing. Assuming a' proximately thè stiffness is linear (rollers in contact with tracks) at thè same axial load, thè axial deflection is smaller in a preloaded...

ò with preload ò without preload ò con precarico ò senza precarico Fig. 4.1 (1) System without preload - sistema senza precarico (2) Preload diagram - sistema con precarico Fo Fx = System with preload Fo - forza assiale esterna ò = Axial deflection - spostamento assiale

TECHNICAL SPECIFICATIONS SPECIFICHE TECNICHE5. FRICTION ■ As for thè bearings, thè friction depends on many fac-tors, thè most important of which are: ■ preload ■ viscosity and amount of thè lubricant ■ applied load ■ hearing size ■ rotational speed i.e.: ■ A bigger preload turns out in a bigger rolling friction torque ■ Tightening values affect considerably riction values. As for RTB bearings thè fixing of thè inner ring screws reduces to zero thè dimensionai c r inner axial clearan-ce as well as thè elastic comprssion of thè inner ring, in generai we recommend to use bolt class 10.9 and recommend...