Product Selection Guide
To reduce complexity and cost of a design, it is important to accurately size a motor/lead screw
combination. Below are a few simple steps in selecting the necessary components for a given application.
- Step1 - Choosing a motor NEMA size(Force requirements)
- Here is a general overview of the output thrust vs. NEMA size:
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NEMA Sizes |
Max. Thrust |
Recommended Load Limit |
NEMA 8 |
78N (17.5lbs) |
43N (9.7lbs) |
NEMA 11 |
230N (51lbs) |
150N (34lbs) |
NEMA 14 |
450N (100lbs) |
230N (52lbs) |
NEMA 17 |
710N (160lbs) |
230N (52lbs) |
NEMA 23 |
1400N (315lbs) |
920N (210lbs) |
NEMA 34 |
2400N (540lbs) |
2160N (485lbs) |
- As the NEMA size of the motor is increased, the output thrust of the actuator is consequently increased.
- Step2 - Choosing a screw lead(Force and Speed requirements)
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After estimating the required thrust and choosing a NEMA size that may fi t your application, the speed and acceleration of the load must be consideredand evaluated to choose an appropriate screw lead.
Due to the nature of lead screws, the output speed and output thrust achievable by a motor/lead screw combination are two inversely proportional variables (i.e., increasing the required thrust will lower the achievable speed for a motor/lead screw combination). Therefore, the maximum output force of a system is lowered for applications that require higher speeds. For complete motor/lead screw selection data, please refer to the speed/thrust curves for each NEMA size.
- Step3 - Lead Screw Material
- There are many inter-related variables to consider when selecting the right linear motion system for your application. Your load and speed requirements will determine other variables such as the size of motor, the lead of the screw and ultimately the voltage and current requirements of your electronic motor drive. Depending on your application, trade-offs can be made with many variables as your finalize the system that will meet your performance, form factor and cost specifications.
- Quantify these basic variables first :
- • Load that you need to move (or push – Thrust)
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- • Velocit
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- • Distance to travel (Stroke)
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- • Time required to move from point A to point B (Acceleration required)
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- • Torque requirements of your entire system
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- • How much backlash is acceptable in your system?
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- • What is the required positional repeatability?
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- • Is this a Vertical or Horizontal orientation?
- Using the PRODUCT SELECTION SYSTEM along with the associated Nema motor frame size pages in the next sections, you will then be able to drill down to specific c part numbers for both the lead screw and the associated step motor. The linear system is ordered as two part numbers.
- ※ Note : A linear ststem must be ordered as two part numbers.