GUIDE TO ROTARY
INDEX TABLES
Your Guide to Rotary Index Tables
Rotary index tables are essential tools in manufacturing and automation. They are designed to precisely position parts or assemblies for various processes. Rotary table indexes are built to meet your specific demands — whether your operation needs positioning for welding, machining or inspection, these devices provide accuracy.
Use rotary index tables to maximize consistency across your operation. They perform effectively in a range of industries, from aerospace to consumer goods. You can find rotary index tables somewhere in virtually every manufacturing industry. With robust motors and precise mechanisms, they can handle complex positioning without sacrificing results. Investing in reliable indexing tables gives your operation critical efficiency and accuracy where you need it most.
What Is a Rotary Index Table?
Rotary index tables, also called indexing tables, rotate on a platform or fixture in set increments. These rotations allow for accurate workpiece positioning during sequential tasks. With this positioning and stability, operations can efficiently complete automated manufacturing processes.
How Do Rotary Index Tables Work?
Rotary index tables are usually positioned along a vertical axis or can be mounted horizontally. When mounted horizontally, there can be a tailstock to support the weight of longer workpieces between centers. They rotate in fixed increments, letting multiple processes — like cutting, drilling, assembling or inspecting — happen sequentially without manual repositioning.
Once the workpiece is loaded onto the table, the table rotates to the exact angle needed for each step. The table securely holds the piece through each task until the workpiece is ready.
Rotary index tables rely on cam-driven or motorized drive systems to ensure smooth, accurate movement. The drive systems use a mathematical motion curve to precisely position pieces as needed. Additionally, the indexing table accounts for load speed, weight and precision requirements to ensure best results.
All of our rotary indexers are cam-driven. On small tables, you have the choice of either a worm gear motor or a helical bevel gear motor. For larger rotary index tables, a helical bevel gear motor is most commonly used.
Applications in Manufacturing
Indexing tables are critical to many manufacturing processes. Their ability to precisely position workpieces for consecutive operations makes them essential for machining, assembly, inspection and other areas. Key manufacturing applications for rotary index tables include:
- Machining: Rotary index tables let facilities position components for milling, drilling and cutting. With index tables, the equipment can work on multiple workpiece sides without manual repositioning. This feature is invaluable for machining since it improves speeds and accuracy.
- Assembly: Automated assembly lines also use rotary index tables. These tables rotate parts, consistently aligning them for bonding, joining or fastening to reduce high-volume production errors.
- Inspection and testing: Facilities can benefit from 360-degree positioning with index tables. Seamless table rotation allows for thorough and efficient inspections or testing.
- Labeling: Consumer goods manufacturing also uses rotary index tables. They rotate products for packaging and label application, reducing production time.
- Device manufacturing: Medical device manufacturing relies on index tables for assembly and inspection. Tables easily maneuver delicate medical components for precise, repeatable processes.
- Welding: Welding also benefits from index tables. Industries like aerospace and automotive require tables for rotating large workpieces. Precise rotation allows for welding in hard-to-reach places without sacrificing quality or safety.
Types of Rotary Index Tables
Rotary index tables come in several designs. Each option accommodates different manufacturing processes and requirements, meeting your unique needs.
Each type offers specific precision, speed and load capacity, from high-speed production lines to heavy-duty machining.
Configurations of Mechanical Indexers
Rotary index tables, also called mechanical indexers, come in various configurations. Each works with different manufacturing needs, so making the right choice is essential. The three main configurations offer excellent benefits, depending on the application.
1. Cam Index Drives
Cam-driven indexers are popular configurations thanks to their high accuracy and smooth motion. In a cam index drive, the cam rotates, transferring motion through a follower to an indexing plate. The indexing plate then stops at precise intervals.
This system is ideal for applications requiring repeatable, fast positioning, like assembly lines. The cam profile ensures smooth acceleration and deceleration, reducing wear and tear. Choose cam index drives for higher speed and lighter load applications that demand reliability.
2. Roller Gear Index Drives
A roller gear index drive is designed to handle heavier loads. These systems use roller gears to transfer torque, maximizing durability and efficiency. Roller gear indexers are often used in metalworking and automotive manufacturing. These industries demand tools that can deliver high torque transmission and strength.
Roller gear indexers also have fewer wear points, improving their longevity. They are ideal for environments requiring strength and precision.
3. Ring Index Drives
Ring index drives are named after their large central opening. This unique opening makes them well-suited to applications that require complete workpiece access, like welding, robotics and large-part assembly.
These systems integrate with tooling or fixtures around the workpiece, increasing efficiency. Ring index drives offer the same high-precision indexing as other systems while providing more space and accessibility.
Types of Cam Indexers
Cam-driven rotary index tables can have significant advantages over other types of rotary index table drive systems, such as gear drives. Cam-driven rotary index tables provide extremely high accuracy because they operate with no backlash. There are several types of commonly used cam-driven rotary index table systems, and each is best for a specific application:
- Barrel cam-driven: Barrel cams use a cylindrical cam to maximize strength. Indexers with barrel cams deliver superior strength without increasing their size.
- Flat/disc cam-driven: These devices feature a flat or disc-shaped cam. Choose flat or disc cams to save space while operating at high speeds with long dwell periods.
- Globoidal cam-driven: Globoidal cams have grooves with tapered walls. This design accommodates cam followers fixed to an output shaft in a “star” configuration.
Selecting a Rotary Index Table
There are important factors to consider when selecting a rotary index table. In principle, it may seem relatively simple to rotate a component and stop periodically at precise angles. In practice, however, it can become a surprisingly difficult challenge to design and build machines that will do this precisely and reliably over the life span expected of modern manufacturing machinery.
- Mass moment of inertia: The number one factor when rotating mass is determining the mass moment of inertia. Knowing the mass moment of inertia is critical for rotary index table sizing. Once you have this figure, professionals can size the index table for the necessary speed.
- Piece size: Another important aspect is the size of the piece being moved. How big is it, and how heavy is it? Size is an obvious constraint, as you need a rotary index table that is large enough for the piece intended. In order for a rotary index table to operate effectively and not cause internal damage, it needs to accelerate and decelerate at proper speeds.
- Precision: How precise does your application need to be? Some applications allow for fairly loose individual stop positions, such as within +/- ¼” and other applications where repeatable positioning within thousands of an inch is necessary. More precise requirements mean selecting an index table that can meet those demands.
How Do You Choose a Rotary Index Table?
When selecting a rotary index table then, it is important to be able to specify the following:
- Accuracy
- Backlash
- Mass moment of inertia
- Acceleration and deceleration
- Speed
- Environment
Understanding each of the points will ensure you get the index table you need. Work with our team to find an existing model or custom solution that fits your application.
Rotary Index Table Machine Components and Options
Rotary Index tables can be configured in a near–infinite number of ways to meet the needs of specific applications.
Common components / accessories that we are asked to provide include:
- Machine Bases
- Slip Rings / Rotary Unions
- Top Dials
- Tooling Frames
- Controls
- Robot Integration
- Custom Coatings
- Motors and Reducers
- Trunnion Riser Weldments
- Mechanical Safety Lockouts
- Explosion Proof Systems
Choose custom components to ensure a rotary index table that meets your specific demands
Rotary Index Table Commissioning
Your manufacturer should offer trained service technicians who are capable of complete testing of both the rotary tables and control systems, including loading, parameters and tuning. Your best option is often to have a pre-programmed VFD panel which can significantly reduce your risk when going through commissioning and start-up.
Getting to a reliable and productive rotary index table installation requires careful application engineering, component selection and integration, and customization to meet specific factors such as the operating environment and proper commissioning. It is important that you discuss commissioning with your rotary index table provider so that you meet the intended functionality and reliability and so that there are no excuses when it comes to any troubleshooting that may occur.
You can learn more about VFD Control Panels and Rotary Index Table Commissioning here.
Rotary Index Table Maintenance
Proper maintenance is critical for protecting rotary index table performance. These machines are integral to your automated processes — downtime can lead to costly delays. Rotary index table failure is often caused by stopping out of position due to lack of maintenance.
While you can perform basic tasks like keeping the table clean and monitoring for unusual sounds, professionals should handle maintenance needs. Indes tables contain sensitive components that improper handling could damage.
Professional maintenance includes:
- Lubrication: Rotary index tables use gears and bearings to provide precision. These components must be kept lubricated to prevent wear and ensure smooth operation. Poor lubrication can lead to overheating or failure. Lubricate is recommended to prevent downtime.
- Alignment checks: Over time, components may shift and wear down. This wear can lead to misalignment, affecting performance. A technician can ensure your table’s indexing accuracy remains within acceptable tolerances. This maintenance task is essential for ensuring precision during operation.
- Motor inspections: Motor inspections are also important for rotary index tables. Their motors can wear down, leading to malfunctions or larger issues. Professionals can detect early malfunction signs and assess motor conditions to protect your device. They will assess motors, cams and other components to address problems before they lead to downtime.
Every rotary index table should have a regular health assessment to prevent issues. Technicians will examine the table for complications, documenting the device’s health. Assessments involve a detailed look at all components, cataloging issues and wear.
Once this is done, technicians can advise you on necessary repairs and next steps. If you are experiencing problems and need help troubleshooting, health assessments are critical. Additionally, schedule regular inspections to protect the device’s life span and ensure it remains efficient.
If you need any technical or service assistance, please contact us for 24-hour support. We will arrive on-site to diagnose and resolve your rotary table issue. Let our expert technicians help you reduce downtime and protect your investment.
Selecting a Rotary Index Table Manufacturer
Rotary index tables are essential for ensuring precision, production scale, reliability and longevity. Without these qualities, your manufacturing workflows could see reduced efficiency and productivity. Motion Index Drives is your partner in selecting and maintaining the best index table for your applications.
That is why it is important that you select a partner with a proven track record of delivering the right machine for the application, producing machinery using the highest quality components and being there to have your back should things not go as you planned.
Features that can be important in your rotary index table include:
- Low friction internal components: Lower friction index drives can require as little as one-third the amperage to operate while producing greater torque.
- Flame-hardened cams and cam followers: Flame-hardened cams and cam followers can withstand forces that cause less robust components to fail prematurely.
Choose an ISO 9001 Certified partner and embrace a culture of continuous improvement. To learn a bit about what we feel makes Motion Index Drives a uniquely valuable rotary index table partner, you can explore here! Contact us online to learn more about our services or request assistance.
