Slewing rings

TGB Slewing Rings – Precision, Strength, and Reliability in Motion

With more than 25 years of expertise in the design and manufacture of slewing rings, slew drives, gears, and power transmission components, TGB Group Technologies has become one of the world’s leading suppliers of motion solutions for industrial, renewable energy, and automation markets. Headquartered in Barcelona, Spain, and supported by production facilities in China, India, and Spain, as well as sales offices and warehouses across Europe, Asia, and the Americas, TGB combines global reach with localized technical support and engineering excellence. Every slewing ring is the result of extensive research, advanced materials engineering, and a commitment to long-lasting performance in demanding environments.

Design and Functionality

A slewing ring, also known as a slewing bearing, is a critical mechanical component that enables rotational movement while supporting heavy axial, radial, and tilting loads. TGB slewing rings are designed to ensure smooth, precise, and controlled motion even under extreme operating conditions. Each unit consists of two concentric rings – an inner and an outer ring – with rolling elements such as balls or rollers positioned between them. The rings are equipped with bolt holes, which may be through holes or threaded holes, allowing for secure attachment to the structure or application frame.

TGB offers slewing rings with external gears, internal gears, or without gears, depending on the design requirements. The gear teeth can also be induction hardened to improve strength and wear resistance by up to 20%, ensuring extended life even in applications subject to high torque and repetitive load cycles. The typical operational lifespan of a TGB slewing ring is around 30,000 load cycles, and each model undergoes rigorous quality testing to ensure compliance with international performance and safety standards.

Load Capacity and Engineering Excellence

TGB slewing rings are engineered to accommodate a combination of axial loads (parallel to the rotation axis), radial loads (perpendicular to the axis), and tilting moments. The company provides detailed load charts and diagrams for each bearing type, showing the maximum permissible loads and moments. By plotting the equivalent axial load and tilting moment on these diagrams, engineers can easily verify whether a slewing ring model is suitable for a specific application.

In addition to static load capacity, TGB’s engineering team considers factors such as dynamic load behavior, vibration resistance, and shock absorption. The use of high-grade steels such as 50MnB, C45B, and 42CrMo4B, combined with precision heat treatment and surface hardening, guarantees structural integrity and durability even in the harshest operating environments.

Applications Across Industries

TGB slewing rings are used in a wide range of sectors that demand precision, safety, and long service life. Common applications include:

• Construction and heavy equipment – loading cranes, demolition machinery, dumpers, and concrete pumps.

• Material handling systems – forklift rotators, port cranes, turntables, and access platforms.

• Renewable energy – wind turbine yaw and pitch systems, solar trackers, and positioning mechanisms.

• Industrial automation – robotic arms, assembly platforms, and positioning systems.

• Agriculture and forestry – harvesters, sprayers, and timber handling machines.

• Aerospace and defense – radar positioning systems and satellite robotics.

This versatility is achieved through a combination of modular design, high manufacturing precision, and custom engineering services that adapt the product to each customer’s technical requirements.

Product Series and Customization

The TGB slewing ring range covers diameters from 150 mm to 7000 mm, with more than 2,400 standard references and 24,000 units available from stock. The company’s product catalog includes several series such as:

• E Series (External Gear) – designed for medium to heavy loads with a wide range of gear modules and hardened teeth options.

• I Series (Internal Gear) – offering compact solutions where external gear design is not suitable.

• SD Series (Without Gear) – optimized for applications requiring external drive systems or direct rotation.

• U and Z Series – specialized designs for unique load or space constraints.

Each model can be ordered with different gear configurations, bolt hole patterns, and material combinations, ensuring that customers receive a slewing ring optimized for performance, cost, and lifespan. TGB also provides engineering consultation and finite element analysis (FEA) support for critical applications.

Installation and Maintenance

TGB emphasizes proper handling, installation, and maintenance to ensure maximum performance and safety. Slewing rings must be transported and stored horizontally to prevent deformation, and should always be handled using lifting bolts in the designated threaded holes. Before installation, both the slewing ring and the mounting surface must be thoroughly cleaned. The soft zone, where the filling plug for balls or rollers is located, must be positioned at 90° to the main load direction.

All mounting holes must be used, and bolts must be tightened according to the prescribed torque values using grade 10.9 bolts. After initial installation, TGB recommends retightening the bolts after 100 working hours and then every three months, or more frequently in high-vibration applications.

Lubrication is another key factor in ensuring long service life. Every slewing ring is pre-lubricated before delivery, but it should be re-greased before first operation and periodically thereafter. Grease must be injected through all grease nipples while rotating the bearing until a fresh bead appears at the seal. For toothed models, the contact surfaces of the teeth should be coated with grease, ideally using a brush. Insufficient lubrication is the most common cause of premature failure, and therefore regular inspection and maintenance are essential.

Performance Characteristics

TGB slewing rings operate within a temperature range of –20°C to +70°C, making them suitable for outdoor and industrial use in diverse climates. The maximum linear raceway speed is 2 m/s in horizontal applications and 1 m/s in vertical applications. Friction torque depends on load, lubrication, preload, and use of spacers, all of which are carefully specified in TGB’s technical data sheets.

Each slewing ring is subjected to strict quality control procedures, including dimensional inspection, material testing, and performance verification. TGB’s integrated manufacturing process ensures consistent quality from raw material to final assembly, supported by ISO-certified production systems and in-house testing laboratories.

Innovation and Global Support

A dedicated R&D department in Barcelona continually develops new designs, materials, and surface treatments to improve bearing life and load performance. The company’s engineers collaborate directly with customers to design custom solutions for new machinery, renewable energy platforms, and automation systems. TGB’s worldwide logistics and after-sales network ensures prompt technical support, spare parts availability, and expert advice in every major industrial region.

Commitment to Quality and Sustainability

TGB Group Technologies upholds a strong commitment to environmental responsibility and efficient manufacturing. The company continuously works to optimize its production processes, reduce energy consumption, and minimize waste. By investing in advanced automation, precision machining, and material recycling, TGB ensures sustainable growth without compromising quality or performance.