Ball Screws
Verified by Mel Sykes, Industrial Supply Chain Specialist - April 2026
bolts with hexagonal heads on a colorful background." width="800" height="533" loading="lazy" style="width:100%;height:auto;border-radius:8px">| Specification | Details |
|---|---|
| Types | Precision ground, rolled, miniature |
| Leads | 1mm to 50mm per revolution |
| Accuracy | C0 to C10 (ISO 3408) |
| Efficiency | 90-95% (vs 30-50% for trapezoidal lead screws) |
| Brands | THK, Hiwin, NSK, Steinmeyer, TBI Motion |
What are Ball Screws?
Ball screws convert rotational motion into linear motion with high precision and efficiency. They consist of a screw shaft with helical grooves and mating ball bearings that roll along the grooves to reduce friction and wear.
Types and Variants
Ball screws come in several types, each tailored for specific applications:
- Precision Ground: These are ground using advanced machinery to achieve very high accuracy (ISO 3408 C0-C10). Ball Screws offers superior precision but at higher costs. Common sizes range from M6 to M50.
- Rolled: Rolled screws use a forming process that's less precise than grinding, offering lower cost and moderate precision (ISO 3408 C7-C10). Sizes typically range from M8 to M20.
- Miniature: These are smaller versions used in compact machines where space is limited. Ball Screws offers high accuracy but with reduced load capacity. Common sizes include M2 to M6.
Materials and Specifications
Ball screws are made from materials that ensure durability and resistance to wear:
- Stainless Steel (AISI 303, A2-70): These grades provide excellent corrosion resistance. AISI 303 is commonly used in applications requiring high lubricity.
- Carbon Steels (EN8, EN19): These offer good mechanical strength and are cost-effective for standard industrial use.
Standards such as ISO 3408 define the accuracy classes (C0 to C10) based on positional error over one revolution. For example, a C0 class screw has an accuracy of ±25 microns per meter.
Selection Criteria
Choosing the right ball screw involves evaluating several factors:
- Load Capacity: Higher lead screws can carry more load but with reduced efficiency.
- Speed and Acceleration: Miniature screws may offer higher speeds due to their smaller size, while larger precision-ground screws provide better acceleration at lower speeds.
- Accuracy Requirements: Applications requiring high precision should opt for C0 or C1 class screws.
UK Suppliers
MLC lists verified suppliers from Companies House such as THK (Japan), Hiwin (Taiwan), and NSK (Japan). These companies have offices in the UK and offer a wide range of products that meet British industry standards. For instance, THK offers over 300 different ball screw models with lead accuracies ranging from C2 to C10.
Common Applications
Ball screws are used across various industries:
- Machine Tools: CNC machines use precision ground screws for accurate positioning and cutting.
- Robotics: Robots benefit from miniature and rolled screws in joint mechanisms, providing smooth motion control.
- Automotive Industry: In steering systems and throttle controls, where reliability under high loads is critical.
For example, the automotive industry often employs EN8 carbon steel ball screws with a C7 accuracy class for their robustness and cost-effectiveness. This material can withstand temperatures up to 250°C and pressures of up to 10 MPa, making it suitable for harsh operating conditions.
References
Frequently Asked Questions
What are Ball Screws?
Ball Screws are engineering components used in industrial applications. Browse verified UK suppliers on MLC.
Where can I buy Ball Screws in the UK?
MLC lists verified UK ball screws suppliers with Companies House data. Browse by product category or search by location.
What are ball screws used for in engineering applications?
Ball screws convert rotational motion into linear motion with high precision and efficiency. They consist of a screw shaft with helical grooves and mating ball bearings that roll along the grooves to reduce friction and wear, making them ideal for precise positioning systems.
What types of ball screws are available, and how do they differ?
Ball screws come in several types including Precision Ground and Rolled. Precision Ground ball screws offer very high accuracy (ISO 3408 C0-C10) but at higher costs, while Rolled ball screws use a forming process that provides lower cost and moderate precision (ISO 3408 C7-C10).
How do you choose the right lead for your ball screw application?
The lead of a ball screw determines the linear travel distance per revolution. Common leads range from 1mm to 50mm per revolution, allowing engineers to select the appropriate speed and precision required for their specific applications.
What accuracy standards apply to ball screws used in UK engineering projects?
Ball Screws adhere to ISO 3408 standards for accuracy ranging from C0 to C10. Higher numbers indicate less tolerance and greater precision, suitable for high-precision applications like CNC machines and robotics.
How do the efficiency rates of ball screws compare to other types of lead screws?
Ball screws offer an efficiency rate of 90-95%, significantly higher than trapezoidal lead screws at 30-50%. This increased efficiency reduces power consumption and heat generation in mechanical systems.
Which brands are commonly used for ball screws in the UK market?
Popular brands include THK, Hiwin, NSK, Steinmeyer, and TBI Motion. Each brand offers a range of precision ground and rolled ball screws suitable for various industrial applications.
What factors influence the cost and availability of ball screws in the UK?
Cost and availability can be influenced by the type (ground vs rolled), accuracy level, lead size, brand, and order quantity. Precision Ground ball screws are more expensive due to higher manufacturing costs but may be readily available through major suppliers like THK and Hiwin.
How do you specify a ball screw for an engineering project?
When specifying a ball screw, consider factors such as required load capacity, speed of motion, precision level (accuracy standard), and environmental conditions. Consultation with manufacturers or suppliers can ensure the selection meets all application requirements efficiently.