Rotary Table Bearings

BRTM Series Rotary Table Bearings

BRTM Rotary Table Bearings are double-direction thrust cylindrical roller combined bearings integrated with an encoded steel scale. This integration enables real-time monitoring and adjustment of rotational accuracy, ensuring the high-precision performance of your machinery. Interchangeable with mainstream YRTM type rotary table bearings for industrial robots, rotary tables and precision automation systems.

Equivalent: Compatible with YRTM Series Rotary Table Bearings

Outer Ring Diameter：240mm——600mm

Precision Class: P5/P4/P2

Axial Dynamic Load: 112kN——355kN

Delivery time: In Stock

What is BRTM Series Rotary Table Bearings?

The BRTM Series Rotary Table Bearing is a high-precision combined bearing based on the double-direction thrust cylindrical roller structure (BRT series), integrated with an advanced steel grating scale system.

Unlike conventional bearings, the BRTM series does not just support loads; it acts as an intelligent motion component. By incorporating a built-in measurement system, it enables real-time monitoring and micro-adjustment of rotational accuracy. This integration eliminates the gap between mechanical movement and position feedback, ensuring that the machinery achieves and maintains ultra-high precision performance throughout its operation.

Features of BRTM Series Rotary Table Bearings

Integrated Sensing Technology: Features a factory-installed steel grating scale, allowing for direct and precise angular displacement measurement.

Multi-Directional Load Capacity: Specifically designed to simultaneously withstand high axial loads, radial loads, and tilting moments.

Enhanced Rotational Precision: The real-time feedback loop minimizes geometric errors, providing superior run-out accuracy.

High Rigidity & Stability: Optimized roller arrangement ensures maximum structural stiffness, critical for heavy-duty machining.

Compact & Seamless Integration: Combining the bearing and encoder into one unit saves installation space and reduces assembly complexity.

Structure of BRTM Series Rotary Table Bearings

The structure of the BRTM Series is engineered for maximum stability and functional integration:

Double-Direction Thrust Component: Two rows of thrust cylindrical rollers handle bidirectional axial loads.

Radial Component: A full complement of cylindrical rollers ensures high radial load capacity.

Integrated Steel Grating Scale: A high-precision measuring scale is mounted directly onto the bearing ring.

Preloaded Design: The assembly is factory-preloaded to ensure zero-clearance and high system rigidity, providing a stable foundation for measurement accuracy.

Integrated Steel Grating Measurement System of BRTM Series

Our steel grating measurement system offers superior performance compared to traditional optical or magnetic encoders, especially in harsh industrial environments.

Key Advantages:

Non-contact Induction: No mechanical wear, ensuring an extended service life.

High Precision: Accuracy levels comparable to high-end optical encoders.

Real-time Correction: Dual-head reading system compensates for radial deviations instantly.

High Dynamics: Supports high speeds and provides high-resolution feedback.

Non-magnetic: No magnetic components, eliminating hysteresis or demagnetization risks.

Environmental Resistance: IP67 protection; resistant to dust, oil, and water pressure.

Space-Saving: Compact design solves the problem of narrow installation spaces.

High Reliability: Exceptional resistance to shock, vibration, and environmental interference.

Full Compatibility: Outputs 1VPP or TTL signals, compatible with mainstream CNC systems.

Technical Configurations:

Accuracy Grades: +/-3 μm, +/-5 μm, +/-10 μm (arc length).

Reference Marks: Standard one mark per 360°, or customized distance-coded marks.

Applications of BRTM Series Rotary Table Bearings

High-Precision CNC Rotary Tables: The core component for 4-axis and 5-axis machining centers.

Indexing Heads: Essential for gear cutting and precise angular increment milling.

Precision Metrology: Ideal for coordinate measuring machines (CMMs) and circularity testers.

Precision Grinding Machines: Ensures high-finish surface quality and stability.

Industrial Robotics & Medical Tech: Applied in high-end robotic joints and medical imaging equipment.

Techspecs of BRTM Series Rotary Table Bearings

Parameter	Specifications
Outer Ring Diameter	240mm — 600mm
Precision Class	P5 / P4 / P2 (Ultra-precision)
Axial Dynamic Load (Cr)	112kN — 355kN
Integrated Scale Accuracy	+/-3μm, +/-5μm, +/-10μm
Signal Output	1Vpp (Sine wave) or TTL (Square wave)

How does BRTM Series Rotary Table Bearings work?

The bearing combines mechanical load-bearing with electronic feedback. As the rollers handle axial and radial forces, the integrated steel grating scale rotates with the bearing ring. The sensor head reads angular position data in real-time, allowing the CNC controller to instantly compensate for deviations, maintaining constant high-precision rotation.

How to Install BRTM Series Rotary Table Bearings?

Preparation: Ensure mounting surfaces are clean and meet flatness tolerances.

Alignment: Align the bearing and integrated scale precisely to ensure signal integrity.

Bolting: Tighten mounting bolts in a crosswise pattern using a torque wrench.

Calibration: Connect the cable to the CNC system and perform a signal calibration check.

Price of BRTM Series Rotary Table Bearings

Pricing is determined by the outer ring dimensions, precision grade (P5/P4/P2), and specific measurement configurations (accuracy grade and cable length). Contact our sales team for a customized quote tailored to your project.

Supplier of BRTM Series Rotary Table Bearings

BYBearings is a national high-tech enterprise specializing in the design, R&D, manufacturing, and global sales of precision bearings.

Our core product portfolio includes:

Crossed Roller Bearings

BRT/BRTM Rotary Table Bearings

Robot Bearings (Harmonic & RV Reducer Bearings)

Crossed Tapered Roller Bearings

At BYBearings, we provide more than just products—we provide precision solutions. Backed by rigorous quality control and technical expertise, we empower your machinery to achieve high-precision, intelligent operation.

BRTM

Model Number	d (mm)	D (mm)	H (mm)	H1 (mm)	C (mm)	D1 (mm)	J (mm)	J1 (mm)	Ca (kN)	Coa (kN)	Cr (kN)	Cor (kN)	Weight (Kg)
BRTM150	150	240	40	26	12	214	165	225	112	630	56	170	6.2
BRTM180	180	280	43	29	15	244	194	260	118	710	69.5	200	7.7
BRTM200	200	300	45	30	15	274	215	285	120	765	81.5	220	9.7
BRTM260	260	385	55	36.5	18	345	280	365	160	1060	93	290	18.3
BRTM325	325	450	60	40	20	415	342	430	275	1930	120	345	25
BRTM395	395	525	65	42.5	20	486	415	505	300	2280	186	655	33
BRTM460	460	600	70	46	22	560	482	580	355	2800	200	765	45

Production Process

Blueprint · Designing Precision

Given the structural characteristics of crossed roller bearings (rollers arranged in a 90° cross pattern), our technical team uses 3D CAD and finite element analysis (FEA) software to accurately calculate raceway angles, spacing, and interference.

Customizing products based on customer operating conditions, we benchmark against P2/P4/P5 tolerance classes and simulate post-assembly rotational precision in advance. The blueprint serves as the sole standard guiding all subsequent turning, grinding, and inspection processes.

Turning & Grinding · Rough to Mirror

Turning and grinding are the core processes that determine the bearing's geometric precision. We use high-rigidity CNC lathes for step-by-step ring processing, ensuring basic inner/outer diameter and raceway dimensions through rough, semi-finish, and finish turning while leaving grinding allowances.

We employ plunge grinding with formed grinding wheels for the V-shaped raceways of crossed roller bearings, and perform combination matching for the split inner/outer rings to ensure rotational plane runout meets P5 or higher standards.

Assembly · Interlocking Precision

The assembly of crossed roller bearings is more delicate than standard bearings: rollers must be arranged in an alternating cross pattern and precisely guided by spacers or cages.

All components are ultrasonically cleaned, dried, and grouped according to measured dimensions. High rigidity and stable torque are then imparted to the crossed roller bearings through negative clearance or preload adjustments. Assembly is completed in a constant temperature and humidity cleanroom to ensure P4/P2 level precision.

Inspection · Not Missing a Micron

As tolerance classes P5, P4, and P2 become progressively stricter, our inspection equipment and processes are upgraded accordingly:

We use high-precision roundness measuring instruments for dimensional tolerances, dial indicators with dedicated test mandrels for radial and axial runout, profilometers and Coordinate Measuring Machines (CMM) to verify raceway profiles and angles, and dedicated clearance and torque testers to determine clearance and starting torque.

Packaging · Anti-Rust & Protection

The packaging process is equally strict, ensuring zero loss of precision for the crossed roller bearings from the factory until pre-installation.

Eco-friendly anti-rust oil is evenly sprayed to ensure no residual particles in the inner cavity. Each bearing is vacuum-sealed in a thickened PE bag and film for water and dust protection, then boxed using wrapping tape. The outer carton is lined with high-density foam and pearl cotton to prevent transport collisions, and is marked with the model, precision grade (P5/P4/P2), and production batch number.