How to Size an Electric Slide Table for Load, Stroke and Speed
To size an electric slide table correctly, we need to evaluate the total moving load, load position, required stroke, travel speed, acceleration, mounting orientation, positioning requirements and available machine space together. Selecting a slide table from payload capacity alone can lead to unsuitable loading, limited travel margin or less effective motion performance.
At Unitop Automation, our team helps manufacturers and machine builders review these application conditions before comparing electric slide table options for positioning, handling, assembly, inspection and other automation processes.
Start With the Application, Not the Slide Table
Before we compare electric slide table models, we first define what the machine actually needs the axis to do. This prevents us from selecting an actuator simply because its catalogue payload or maximum speed appears sufficient.
We normally begin by asking:
A slide table with sufficient nominal load capacity may still be unsuitable if the tooling is positioned far from the carriage centre, acceleration is high or the installation orientation changes the forces acting on the guide.
Manufacturers comparing compact motion options can also review our electric slide table range in Malaysia, including ENA, ENB and ES Series.
1. Calculate the Total Moving Load
Electric slide table load calculation should include everything that moves with the carriage, not only the workpiece.
When we calculate moving mass, we normally include:
A useful starting formula is:
For example, assume a workpiece weighs 2 kg, the fixture weighs 1.2 kg and a gripper with mounting hardware weighs 0.8 kg.
The 4 kg figure is only the starting point. The selected slide table must still be checked for the intended speed, acceleration, mounting orientation and load position.
If the moving tooling includes a gripper, its weight, mounting plate and brackets should also be included in the calculation. Our EHC Series small electric gripper is one example of a component that may form part of the total moving load.
Final allowable load should always be checked against the technical specifications of the selected actuator model.
2. Check the Load Position and Moment
Weight alone does not determine whether an electric slide table is suitable for the intended load. The position of that load relative to the carriage and guide system is also important.
A compact 3 kg load mounted close to the carriage can create very different guide loading from the same 3 kg load installed on a long bracket extending away from the carriage.
Offset tooling can create moments in several directions. Important factors include:
The farther the load centre is from the supported guide area, the greater the potential moment on the guide system.
Our practical sizing approach therefore treats moving mass and load position as separate checks. The complete tooling arrangement should be compared with the manufacturer's allowable load and moment specifications before a model is confirmed.
3. Choose the Required Stroke
Electric slide table stroke should cover the complete machine movement, including necessary clearance—not simply the distance between two process positions.
Suppose a pick position and a place position are 150 mm apart. A 150 mm stroke does not automatically mean the application requires only a 150 mm slide table.
Stroke selection may also need to account for:
For example, a gripper may need to move beyond the nominal transfer position so that it clears a fixture before another axis begins moving.
Defining the complete motion path before choosing the stroke reduces the risk of insufficient travel while avoiding unnecessary actuator length and machine footprint.
4. Determine the Required Speed
Electric slide table speed should be based on the movement time available within the machine cycle rather than simply choosing the highest maximum speed available.
A simplified starting relationship is:
For example, if an axis needs to travel 300 mm and the motion portion of the cycle allows 0.75 seconds:
This calculation represents an average requirement only. A real motion profile normally includes acceleration and deceleration, so the actuator does not instantly reach its commanded maximum speed.
The complete machine cycle may also include:
Increasing maximum travel speed does not necessarily reduce total machine cycle time if other process operations consume most of the available cycle.
When slide-table motion forms part of a larger machine upgrade, cycle time, layout and machine interfaces should also be reviewed together. Our guide on integrating a new machine into an existing production line explains these wider considerations.
5. Consider Acceleration, Not Only Maximum Speed
Acceleration can significantly affect actuator loading, especially when moving heavier or offset tooling.
Higher acceleration may:
A slide table rated for a particular maximum speed should not automatically be assumed suitable for every payload at that speed. The complete motion profile—including acceleration, travel, deceleration and stopping—should be considered.
For applications with substantially different speed and acceleration requirements, another motion technology may be more appropriate. A linear motor solution such as our EDL Series linear motor may also be considered.
6. Check the Mounting Orientation
Mounting orientation changes how forces act on an electric slide table and should be confirmed before final model selection.
| Mounting Direction | What We Review |
|---|---|
| Horizontal | Moving mass, speed, acceleration, offset load and guide moment |
| Vertical | Moving mass, gravity, holding requirements and travel direction |
| Side-mounted | Guide loading, offset moment and installation rigidity |
| Inclined | Combined gravity effects, guide loading and motion forces |
Vertical applications deserve particular attention because gravity acts continuously on the moving system. Motor force, braking or holding requirements and allowable payload may therefore differ from those of a horizontal installation.
Final mounting suitability should always be verified against the selected model's official technical specifications.
7. Review Accuracy and Repeatability Requirements
Accuracy and repeatability are related but different electric slide table selection criteria.
Positioning accuracy describes how closely the axis can achieve its commanded position.
Repeatability describes how consistently the axis can return to the same position over repeated cycles.
The required performance depends on the application. Examples include:
A transfer application may tolerate a different positioning requirement from a precision inspection or assembly station.
8. Check Machine Space and Tooling Layout
An electric slide table can satisfy load, stroke and speed requirements yet still be unsuitable if it does not physically fit the machine.
The installation envelope should account for:
For example, an actuator may provide the required 200 mm stroke but create interference between the motor and machine frame at one end of travel. The complete actuator, tooling and machine layout therefore needs to be checked rather than considering stroke alone.
9. Match the Slide Table Type to the Application
After defining load, moment, stroke, speed and installation requirements, suitable electric slide table configurations can be compared.
| Series | General Positioning | Applications We May Evaluate It For |
|---|---|---|
| ENA Series | Platform micro type with compact positioning format | Electronics, semiconductor equipment, precision positioning and testing |
| ENB Series | Semi-sealed micro electric slide table | Space-sensitive automation, inspection, assembly and handling |
| ES Series | Compact micro electric slide table | Compact automation requiring controlled positioning and responsive motion |
For compact platform-style positioning, the ENA Series electric slide table may be evaluated once the load, stroke and motion requirements are defined.
For space-sensitive applications, the ENB Series semi-sealed electric slide table can also be compared against the required installation envelope and motion conditions.
The ES Series micro electric slide table provides another compact option for applications requiring controlled positioning and responsive motion.
The correct model still depends on official specifications and actual application conditions.
If the application requires a different actuator construction or travel format, a fully sealed ball-screw linear actuator such as the ETB Series may also be considered.
Quick Electric Slide Table Sizing Checklist
Our practical application review sequence is:
Before confirming an electric slide table model, check:
If the application data is incomplete, our automation component sizing and consultation service can help review load, stroke, speed, mounting and other selection factors before final model confirmation.
Common Electric Slide Table Sizing Mistakes
Sizing From Workpiece Weight Only
The workpiece may represent only part of the moving mass. Grippers, brackets, fixtures, adapter plates and other moving components should also be included.
Ignoring an Offset Load
A load within the nominal kilogram rating may still create excessive moment if it is positioned too far from the carriage. Both mass and load-centre position should be evaluated.
Choosing Stroke Equal to Exact Travel Distance
Point-to-point distance alone may not provide enough room for tooling clearance, homing or fixture geometry. The complete movement envelope should be defined first.
Selecting Based Only on Maximum Speed
Maximum speed is only one part of the motion profile. Acceleration, deceleration, settling time and process dwell also influence the real cycle time.
Ignoring Installation Orientation
Horizontal and vertical installations do not necessarily create the same load conditions. Gravity and holding requirements need particular attention in vertical applications.
Example Electric Slide Table Selection Process
Consider a hypothetical machine that moves a component between two fixtures.
The workpiece weighs 1.5 kg, while the gripper, mounting plate and brackets add another 2 kg. The required point-to-point movement is approximately 250 mm, and the transfer must fit within a defined machine cycle.
Our application review follows this sequence:
- Calculate the moving mass.
The initial total is approximately 3.5 kg before any additional moving accessories are added. - Check the load position.
Determine whether the gripper and workpiece sit close to the carriage centre or create an offset moment. - Determine the actual required stroke.
The 250 mm process distance may require additional travel for tooling or fixture clearance. - Calculate the available movement time.
Separate actuator travel time from gripping, sensing and other process operations. - Review acceleration and deceleration.
Determine whether the required motion can realistically be achieved within the available travel. - Confirm the mounting direction.
Review any additional requirements created by horizontal, vertical, side-mounted or inclined installation. - Review positioning requirements.
Define the accuracy and repeatability needed at each process position. - Compare suitable models against official specifications.
Final model selection follows only after the application conditions have been defined.
This process helps prevent an electric slide table from being selected on one headline specification while other mechanical or motion requirements are overlooked.
Need Help Confirming Your Electric Slide Table Requirements?
Electric slide table selection should consider load, stroke, speed, mounting orientation and tooling together. At Unitop Automation, our team can help review these application requirements before final model selection.
Discuss Your Application RequirementsFrequently Asked Questions
Conclusion
In summary, correct electric slide table sizing requires load, stroke, speed, acceleration, mounting arrangement and machine space to be evaluated together. Payload or maximum speed alone is not enough to confirm whether a model suits the complete application.
At Unitop Automation, our team supports manufacturers and machine builders by reviewing these motion requirements and comparing suitable electric slide table options against the relevant technical specifications.