Acme Screw Material Specifications
Materials used in Nook acme nuts have been selected for low friction, minimum wear, long life, and clean operation.
Bronze Acme and Trapezoidal Nut
Special high tensile bronze is selected for our smooth running, anti-wedging bronze nuts.
- Material: Nook Bronze
- Tensile Yield: 50,000 psi
- Tensile Ultimate: 65,000 psi
- Hardness: HB75
- Dynamic co-efficient of friction: 0.125 with Nook Lubricant
Nut specifications can be found in the Quick References on pages 18-19 and 60 of our Precision Screw Assemblies Catalog. Flange and nut dimensions are listed with the appropriate screw data on pages 34-59 and 64-69.
Plastic Acme and Trapezoidal Nut
The high strength and inherent lubricity of plastic Acme and Trapezoidal nut material can result in product life that can equal or exceed conventional nut materials.
- Tensile Strength at 70°F: 8,000 psi
- Compressive Strength at 70°F: 16,000 psi
- PV Limit: 2,700 lubricated
- Co-efficient of friction: 0.10 lubricated
PowerAc™ Flanges for Bronze and Plastic Nuts
Made from carbon steel with black oxided finish. See page 11 for Mounting and Pinning Acme Nut flange installation instructions.
|SCREW TYPE||MATERIAL||THREAD CLASS||LEAD ACCURACY||SCREW DIA.||SCREW LENGTHS|
|Centralizing 2C or Stub||±.0003"/" up to 21⁄2" dia.||1⁄4" to 6"||Limited only by material availability|
|Stainless||Centralizing 2C or Stub||±.0003"/" up to 11⁄2" dia.||1⁄4" to 11⁄2"||Limited only by material availability|
|Milled||Alloy||Centralizing 2C or 3C||±.002"/ft||1⁄2" to 3" (single starts)||up to 96"|
|Stainless||Centralizing 2C or 3C||±.002"/ft||1⁄2" to 3" (single starts)||up to 96"|
|Ground||Alloy||Centralizing 3C or 4C||±.0005"/ft||1⁄4" to 4"||up to 120"|
|Stainless||Centralizing 2C or 3C||±.0005"/ft||1⁄4" to 4"||up to 120"|
|ACME & TRAPEZODIAL||STAINLESS STEEL|
|Screw Material||4140||300 Series|
|Minimum Hardness||200 Brinnel||170 Brinnel|
|Tensile Ultimate Strength||95,000 psi||85,000 psi|