Product Classification: Threaded Rod, Lead Screw & Studding
In industrial terminology, threaded rod (also referred to as studding, all-thread, or fully threaded bar) denotes a continuous length of metal with helical threads extending the full length of the component. When utilized for motion control applications—such as converting rotary motion to linear motion—it is termed a lead screw or power screw. Our product line encompasses both general-purpose threaded rod for fastening applications and precision lead screws for mechanical actuation systems.
Product Classification: Lead Screw vs. Threaded Rod
Understanding the distinction between these product categories is essential for proper specification:
| Category | Description | Typical Application |
|---|---|---|
| Lead Screw | Precision thread form (often Acme or trapezoidal) designed for linear motion conversion | CNC actuators, linear stages, 3D printers, industrial lifts |
| Threaded Rod (Studding) | Continuous thread along full length; standard metric or inch thread profiles | Structural anchoring, mounting studs, tie rods, tension members |
| Precision Threaded Bar | Ground or rolled thread with tighter tolerances; may be partial or full thread | Machine tool components, precision adjustment mechanisms |
Thread Standards: Industry Norms
All products conform to internationally recognized thread standards:
| Standard | Thread Form | Common Applications |
|---|---|---|
| ISO Metric (DIN 13) | 60° profile, coarse (M) or fine (MF) pitch | General mechanical, European/Asian equipment |
| ANSI/ASME B1.1 (UNC/UNF) | 60° profile, unified thread | North American industrial, aerospace |
| Acme (Centralizing / Stub) | 29° trapezoidal profile | Lead screw applications, high-load linear motion |
| Trapezoidal (Tr DIN 103) | 30° profile | European lead screw standard, machine tools |
Length Specifications: Standard Stock & Custom
| Stock Length | Tolerance | Custom Range |
|---|---|---|
| 1,000 mm | ±2.0 mm | 100 mm – 6,000 mm |
| 2,000 mm | ±3.0 mm | Custom diameters: M4 – M64 |
| 3,000 mm | ±4.0 mm | Custom pitches: coarse, fine, or special |
Stock lengths are precision-cut with deburred ends. For custom lengths exceeding 3 meters, please consult for manufacturing feasibility and lead time.
Material Grades: High-Strength Selection
| Material | Grade / Specification | Tensile Strength | Yield Strength | Typical Hardness |
|---|---|---|---|---|
| Carbon Steel | Grade 8.8 (ISO 898-1) | 800–880 MPa | 640–720 MPa | 22–32 HRC |
| Carbon Steel | Grade 10.9 (ISO 898-1) | 1,000–1,100 MPa | 900–1,000 MPa | 32–39 HRC |
| Carbon Steel | Grade 12.9 (ISO 898-1) | 1,200–1,220 MPa | 1,080–1,100 MPa | 39–44 HRC |
| Carbon Steel | Grade B7 (ASTM A193) | 860–1,000 MPa | 720–860 MPa | 25–35 HRC |
| Stainless Steel | A2 (304) / A4 (316) | 500–700 MPa | 200–400 MPa | 80–95 HRB |
| Stainless Steel | B8M Class 2 (316) | 550–750 MPa | 240–450 MPa | 85–100 HRB |
| Alloy Steel | 4140 / 4340 (Heat Treated) | 1,000–1,400 MPa | 850–1,200 MPa | 28–45 HRC |
Manufacturing Processes: Rolled vs. Cut Threads
| Process | Characteristics | Suitability |
|---|---|---|
| Thread Rolling | Cold-forming process; work-hardened surface; superior fatigue resistance; consistent thread profile | High-volume production, dynamic loading applications |
| Thread Cutting | Material removal; precise tolerances; suitable for custom pitches and short runs | Prototypes, custom specifications, large diameters |
| Thread Grinding | Precision finishing; ultra-tight tolerances; smooth surface finish | Lead screws for precision motion control |
Surface Treatments & Coatings
| Finish | Carbon Steel | Stainless Steel | Corrosion Resistance |
|---|---|---|---|
| Zinc Plating (Clear/Yellow) | ✓ | — | 72–120 hrs salt spray |
| Zinc-Nickel | ✓ | — | 500–1,000 hrs salt spray |
| Geomet / Dacromet | ✓ | — | 500–1,000 hrs, no hydrogen embrittlement |
| Black Oxide | ✓ | ✓ | 24–48 hrs (with oil) |
| Passivation | — | ✓ | 500–1,000 hrs |
| Electropolishing | — | ✓ | Enhanced corrosion, bright finish |
| Phosphate (Manganese/Zinc) | ✓ | — | 48–96 hrs, oil retention |
Straightness & Tolerances
| Parameter | Standard Commercial | Precision Grade |
|---|---|---|
| Straightness (per 1,000 mm) | ≤ 1.0 mm | ≤ 0.3 mm |
| Thread Runout | ≤ 0.2 mm | ≤ 0.05 mm |
| Diameter Tolerance (Major) | ±0.1 mm | ±0.02 mm |
| Thread Class | 6g (external), 6H (internal) | 4g / 4h (precision) |
| Parameter | Metric Threaded Rod | Lead Screw (Acme/Trapezoidal) |
|---|---|---|
| Diameter Range | M3 – M64 | 6 mm – 80 mm (Acme); Tr10 – Tr60 |
| Thread Pitch | Coarse (standard) or fine (custom) | 1 mm – 12 mm (custom) |
| Length Range | 100 mm – 6,000 mm | 100 mm – 4,000 mm |
| Standard Stock Lengths | 1,000 / 2,000 / 3,000 mm | 1,000 / 2,000 mm |
| Material Grades | 8.8, 10.9, 12.9, B7, A2, A4, 4140 | 10.9, 12.9, 4140, A2, A4 |
| Thread Form | ISO Metric 60°, UNC/UNF 60° | Acme 29°, Trapezoidal 30° |
| Thread Class | 6g (rolled), 6g/4g (cut/ground) | 2C / 3C (Acme), 7e / 7h (Tr) |
| Surface Finish | Zn, Zn-Ni, Geomet, Black Oxide, Passivation | As specified |
| Straightness (per m) | 0.3 – 1.0 mm | 0.1 – 0.5 mm |
| Certification | EN 10204 3.1 available | EN 10204 3.1 available |
| Diameter | Lead (mm) | Dynamic Load Rating (kN) | Critical Speed (rpm @ 1m length) |
|---|---|---|---|
| Tr12 x 3 | 3 | 3.5 | 3,800 |
| Tr16 x 4 | 4 | 6.2 | 3,200 |
| Tr20 x 4 | 4 | 8.5 | 2,800 |
| Tr24 x 5 | 5 | 12.0 | 2,400 |
| Tr30 x 6 | 6 | 18.5 | 2,000 |
Values are representative; consult engineering for specific application calculations.
| Inspection | Method | Acceptance |
|---|---|---|
| Thread Profile | Optical comparator / thread gauges | 100% on critical features |
| Straightness | Precision straight edge / laser alignment | Per specification |
| Diameter | Micrometer / laser micrometer | ±0.02 mm (precision grade) |
| Hardness | Rockwell / Vickers tester | Per material grade |
| Mechanical Properties | Tensile test (per batch) | Per ISO 898-1 / ASTM A370 |
| Surface Finish | Visual / profilometer (Ra) | As specified |
Documentation Available:
Material Test Reports (EN 10204 3.1 / 3.2)
Dimensional Inspection Reports
Heat Treatment Certifications
Coating Certifications
Full Lot Traceability
| Custom Parameter | Options |
|---|---|
| Diameter | M3 – M64, custom diameters |
| Pitch | Standard metric coarse/fine, Acme, trapezoidal, special |
| Length | 100 mm – 6,000 mm |
| Material | Carbon steel (8.8–12.9), stainless (304/316/17-4), alloy (4140/4340) |
| Thread Form | ISO metric, UNC/UNF, Acme, trapezoidal, buttress |
| Surface Treatment | Zinc, Zn-Ni, Geomet, Dacromet, black oxide, passivation, phosphate |
| End Machining | Chamfered, threaded ends, turned down, drilled, tapped |
| Tolerances | Commercial or precision ground |
| Parameter | Details |
|---|---|
| Minimum Order Quantity | Flexible; sample quantities available |
| Stock Items | Selected diameters in 8.8 / A2 / A4, 1m/2m/3m lengths |
| Lead Time (Custom) | 2–5 weeks depending on complexity and quantity |
| Packaging | Bundled, individually wrapped, or custom kitting |
| Shipping | Global export; protective packaging for corrosion prevention |
