In the precision operation of industrial equipment, transmission components act like "joints," determining the accuracy and lifespan of the entire machine. However, many buyers often make mistakes when selecting ball screws and linear guides due to parameter confusion and application mismatches. Nanjing Shuntai (https://www.nanjingshuntai.com/), a company deeply involved in the precision transmission field, will share its practical experience to help you clarify your thinking. I. Selection: Five Common Misconceptions Common Selection Misconceptions (Nanjing Shuntai Helps You Avoid): Misconception 1: Focusing on Diameter, Not Lead. Error: Thinking Larger Diameter is Better. Correct: Diameter primarily affects rigidity and critical speed, while lead directly determines speed and thrust. For high-speed applications, a larger lead should be prioritized, and rigidity should be ensured by increasing the diameter. Misconception 2: Ignoring the Stress Rod Stability. Misconception: For lead screws with a large aspect ratio (slender types), only checking the lifespan without checking the allowable axial load can lead to unstable bending during operation. Correct: For applications with a large aspect ratio, stress rod stability must be checked. Misconception 3: Exceeding the critical speed. Error: Motor speed can be increased indefinitely. Correct: The operating speed must be kept below the critical speed, otherwise severe vibration will occur. Increase the critical speed by changing the mounting method, increasing the diameter, or shortening the span. Misconception 4: Selecting too high or too low an accuracy grade. Error: Blindly pursuing the highest accuracy, or choosing too low an accuracy grade to save money. Correct: Comprehensively consider the equipment's positioning accuracy, repeatability, and budget. Grade C7 is sufficient for most general applications. Misconception 5: Ignoring the importance of preload. Error: Not understanding the role of preload. Correct: Preload eliminates axial play and improves rigidity, but it also increases wear and heat generation. Select preload for high-precision, high-rigidity applications; select light or no preload for light loads and high speeds. II. Installation: Details determine accuracy and lifespan. Many users report that "a new lead screw makes unusual noises after just six months of use." This is likely due to installation problems. Nanjing Shuntai's lead screw installation and commissioning video emphasizes that guideway parallelism errors exceeding 0.02mm/m will cause abnormal wear of the slider; coaxial misalignment of the bearing seats at both ends of the lead screw is a major cause of vibration. Jining local customers can schedule on-site installation services, where technicians will perform on-site calibration with a laser interferometer to ensure optimal performance of each device. III. Maintenance: Simple Operations Extend Lifespan by Three Times Regular lubrication is the lifespan of transmission components, but using the wrong grease can be detrimental. Nanjing Shuntai's technical advice: Use lithium-based grease for high-speed lead screws, extreme-pressure grease for heavy-duty guide rails, and high-temperature grease if the ambient temperature exceeds 80°C. IV. Summary: The selection of ball screws and linear guides requires rigorous engineering calculations. By keeping in mind the five core factors of "load, speed, accuracy, rigidity, and lifespan," following a scientific selection process, and leveraging the expertise of a professional team like Nanjing Shuntai, you can easily avoid 90% of selection errors and create a stable, precise, and durable linear motion system for your equipment.