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RTB AMS Combined axial-radial roller bearings, with integrated inductive encoder

RTB AMS Combined axial-radial roller bearings, with integrated inductive encoder

Product catalog summary

Overview: The document provides comprehensive technical specifications and guidelines for precision bearings used in machine tools, focusing on combined axial-radial roller bearings and needle roller bearings. It includes sections on technical specifications, dimensional tables, and special configurations.

RTB Series: This section discusses combined axial-radial roller bearings designed for indexing tables and high-speed applications. Key features include high axial stiffness, capacity to bear high tilting moments, and suitability for rotating and positioning tables. The RTB series is available in greased and ungreased versions, with specific lubrication requirements.

Technical Specifications: The document outlines the general description, stiffness, assembly instructions, preload concepts, friction, operating speed, and lubrication for RTB bearings. It emphasizes the importance of high stiffness, load rating, and rotational accuracy, achieved through precise machining and linear contact of rolling elements.

SRB Series: This section details combined needle and roller bearings for ball screw support, highlighting their technical specifications and constructive indications for adjacent parts. The SRB series includes various configurations like SRB-L, SRB-T, SRB-F, and SRB-FL, each with specific technical details.

Special Configurations and Designations: The document includes information on special configurations for both RTB and SRB bearings, along with their respective designations. It also covers precision locknuts and customized crossed roller bearings, providing examples of customized applications.

Tolerances and Standards: Tolerance tables for RTB bearings are provided, detailing dimensions for inner and outer rings, shaft washers, and housing washers. The document adheres to UNI ISO 76 and UNI ISO 281 standards for load ratings and life calculations.

Company Information: Mondial and UNITEC are highlighted as leading companies in the design, manufacturing, and distribution of precision bearings, with certifications like ISO 9001 and ISO 14001. They offer comprehensive technical and logistic support to meet unique application requirements.

Technical Specifications Overview:
1. General Description: RTB HS bearings are designed for high-speed applications such as turning and milling machine tables. They are available in two versions: ungreased (RTB***HS) and greased (RTB***HS-G) with lithium soap-based grease.
2. Stiffness: The stiffness values consider the deformation of all bearing components and assembled parts. Axial stiffness is calculated with the load applied top-down.
3. Assembly Instructions: For high-speed applications, avoid interference or press fit during mounting to facilitate operating speed.
4. Operating Speed: Operating speeds are determined experimentally. Continuous speeds are considered nominal, while peak speeds are achievable in brief transitory phases.
5. Lubrication: Grease type is lithium soap with a viscosity of 55 cSt at 40°C, NLGI 2. Relubrication intervals are 500 hours under optimal conditions and speeds below nominal. For higher speeds, intervals should be 330 hours.
6. Preload and Temperature Differences: Temperature differences between the shaft and housing can affect bearing operation. Higher inner ring temperatures increase radial preload and contact stress, leading to increased rolling torque and heat generation. Lower inner ring temperatures decrease preload, affecting rigidity and causing wear.
Dimensional and Performance Data: Tables provide detailed specifications for various RTB models, including friction torque, rolling torque, operating speeds, lubrication requirements, and dimensional tolerances. Key parameters such as bore size, radial and axial stiffness, and preload conditions are outlined.
Recommendations: Ensure proper lubrication and assembly to maintain optimal performance. Regularly check and adjust relubrication intervals based on operating conditions.

Specifications: The document discusses the RTB HS series bearings, which use lithium soap grease with a viscosity of 55 cSt at 40°C. It emphasizes the importance of maintaining temperature differences between rotating and fixed components within a few degrees Celsius to prevent bearing damage. High-speed applications require careful temperature monitoring and control to avoid excessive preload or clearance generation.
Procedures: For new applications with RTB-HS bearings, consulting the technical service is recommended. The document also provides a dimensional table for various RTB HS models, detailing specifications such as axial and radial runout, suitable table diameter, and other dimensions.
Standards and Recommendations: The document highlights the need for an adequate cooling system for bearings in high-speed continuous operations. It also mentions the importance of ensuring that adjacent components can dissipate generated heat.
Technical Specifications: The RTB AMS and RTB ABS series bearings are designed for rotary tables and spindle heads, integrating an inductive angle measuring system. The AMS version uses an incremental measuring system, while the ABS version uses an absolute system. These bearings offer high precision, low resistant torque, and high load capacity, making them suitable for direct drive installations.
Inductive Measuring System: The document describes the AMO inductive measuring system, which is resilient to environmental influences and electromagnetic interference. It provides high accuracy and is suitable for applications requiring precision, such as machine tools. The system offers various configurations with different precision and resolution levels.
Key Data from Tables: The dimensional table provides detailed measurements for different RTB HS models, including part numbers, axial and radial runout, and suitable table diameters. Another table outlines the configurations available for the inductive measuring system, detailing the number of periods per revolution and total accuracy for different bore sizes.

Technical Specifications: The document outlines the technical specifications of the RTB AMS system, highlighting its modularity and ability to be tailored to customer-specific requirements. It provides details on available interpolation factors and emphasizes the importance of contacting the technical department for correct system configuration.
STU-20 Tool: The STU-20 is an optional advanced electronic tool designed to improve the setting procedure of the RTBxxxAMS measuring system. It allows for verification of system functionality before connection to the CN or during operation. Key features include checking power supply, sensor positioning, output signals, and signal accuracy using an integrated oscilloscope function.
Advantages of the System: The RTB AMS system offers several advantages, including:

Inductive measuring system principle that is non-magnetic and resistant to electromagnetic interference.
Real-time output signals ideal for direct drives.
High rotation speed without limitations.
High measuring resolution comparable to optoelectronic systems.
Compact solution simplifying design and manufacturing.
Insensitivity to soiling, with IP67 protected sensors.
Simple installation and quick setting without the need for calibration software.
Stable and reliable function across temperature ranges.

Dimensional Tables: The document includes dimensional tables for various RTB AMS sizes, noting differences in flange thickness and recommendations for sensor head tightening post-bearing mounting. It also provides load ratings and maximum speed specifications.
RTB ABS System: The RTB ABS system is a new generation system offering different precision and resolution levels. It features:

Absolute interfaces such as SSI, BiSS/C, FANUC, and others.
Integrated electronic scanning head.
Measuring scale with a pitch of 1000 µm and precision classes of ±5 µm and ±3 µm.
Self-centering measuring head for easy mounting.
Protection class IP67 for the reading head.

Available configurations are based on a single reading head with integrated electronics, offering different resolution levels and influencing the system's total accuracy.

Specifications: The UNITEC XRB series of crossed roller bearings are characterized by a compact design, the ability to withstand axial loads in both directions, radial loads, and high overturning moments. They are ideal for applications with limited space or where low center of gravity is required.
Applications: Main applications include vertical axis rotary tables, positioning tables, and horizontal and vertical axis spindles of robots. Special executions with mounting interfaces for direct motors are available for superior dynamic performance, high precision, and reduced assembly times.
Customization: UNITEC XRB bearings are designed and produced exclusively upon customer request. They can be supplied with dimensions on demand, precision classes P0, P6, P5, P4, or according to different specifications, and with clearance or preload adjusted during assembly or pre-adjusted.
Configurations: All three basic configurations of UNITEC cross roller bearings can be supplied with fixing holes, laminar rings, and different types of seals upon request.
Customized Applications: Custom solutions are available for specific applications, such as customized XRB for indexing tables and special bearings for rotating nut support.
Tolerances: The document includes detailed tables of tolerances for various precision classes (P0, P6, P5, P4) for both inner and outer rings, as well as thrust bearings. These tables specify deviations, bore diameter variations, width deviations, and radial runout among other parameters.
Disclaimer: The catalogue has been produced with care and attention, and all data have been checked for accuracy. However, no liability is assumed for any incorrect or incomplete data. Modifications may occur due to constant development and expansion of the product range.

Catalog excerpts

RTB AMS Combined axial-radial roller bearings, with integrated inductive encoder-1

PRECISION BEARINGS FOR MACHINE TOOLS CUSCINETTI DI PRECISIONE PER MACCHINE UTENSILI

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RTB AMS Combined axial-radial roller bearings, with integrated inductive encoder-3

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

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RTB AMS Combined axial-radial roller bearings, with integrated inductive encoder-4

MONDIAL UNITEC Mondial is a leading company in the import and distribution of power transmission components. Mondial always provides 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’importazione 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...

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RTB AMS Combined axial-radial roller bearings, with integrated inductive encoder-5

UNITEC, leading company in the design and manufacturing of spec jl precision cylindrical roller bearin 3s for machine tools and general 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 the 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...

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RTB AMS Combined axial-radial roller bearings, with integrated inductive encoder-6

2. STIFFNESS High stiffness, considerable load rating, high rotational accuracy are the essential features of the combined UNITEC RTB bearings. The axial cages with a high number of rolling elements with linear contact as well as a very high precision of the machining permit a precise and rigid movement. The size of the axial and radial rollers as well as of the inner and outer rings are carefully measured in order to obtain. The requested preloads by tightening the cap screws. The tolerances of the preload value are particularly restricted, so that a constant and uniform quality of supplies...

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RTB AMS Combined axial-radial roller bearings, with integrated inductive encoder-7

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...

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RTB AMS Combined axial-radial roller bearings, with integrated inductive encoder-8

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...

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RTB AMS Combined axial-radial roller bearings, with integrated inductive encoder-9

Stiffness values of rolling lements in preloaded con tions Rigidezze relative ai soli elementi volventi in condizioni di precarico teorico Stiffness values of a complete assembled bearing (°) Rigidezze relative al cuscinetto completo in condizioni di installazione di 'ferimento (°) (°) 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...

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RTB AMS Combined axial-radial roller bearings, with integrated inductive encoder-10

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...

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RTB AMS Combined axial-radial roller bearings, with integrated inductive encoder-11

Fig. 3.1 RTB assembly instructions Indicazioni di montaggio per RTB

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RTB AMS Combined axial-radial roller bearings, with integrated inductive encoder-12

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

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RTB AMS Combined axial-radial roller bearings, with integrated inductive encoder-13

δ with preload δ con precarico δ without preload δ 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 δ = Axial deflection - spostamento assiale

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RTB AMS Combined axial-radial roller bearings, with integrated inductive encoder-14

TECHNICAL SPECIFICATIONS SPECIFICHE TECNICHE5. FRICTION ■ As for the bearings, the friction depends on many factors, the most important of which are: ■ preload ■ viscosity and amount of the lubricant ■ applied load ■ bearing size ■ rotational speed i.e.: ■ A bigger preload turns out in a bigger rolling friction torque ■ Tightening values affect considerably riotion values. As for RTB bearings the fixing of the inner ring screws reduces to zero the dimensional c r inner axial clearance as well as the elastic comp1' ssion of the inner ring. In general we recommend to use bolt class 10.9 and recommend...

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