Product Summary

Longze Square Nuts are specialized four-sided internal-thread fasteners manufactured to DIN 557 (Standard/Thick) and DIN 562 (Thin/Flat) standards. Widely used in electrical enclosures, blind nut channels,

furniture assembly, and railway applications, these Longze Square Nuts provide a greater surface contact area than standard hex nuts, which helps prevent loosening in high-vibration environments.

• ✔ Anti-Rotation Geometry: The square shape allows the nut to be held in place by the walls of a channel or a specialized wrench, making it ideal for blind-hole installations.

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• ✔ Enhanced Surface Contact: The four flat sides provide a larger bearing surface against the workpiece, distributing the clamping load and reducing the risk of material indentation.

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• ✔ Versatile Thickness Options: Available in DIN 562 (Thin) for space-constrained electronics and DIN 557 (Thick) for heavy-duty structural applications.

Key Features of Square Nuts

• Ideal for T-Slot Channels – Perfectly sized to slide into aluminum profiles and steel channels for adjustable mounting points.

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• Self-Locking Potential – When placed in a tight-fitting square recess, the nut cannot rotate, allowing for one-sided bolt installation.

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• Durable Material Selection – Produced in Carbon Steel (Class 5, 8) E Stainless Steel (A2/A4) for superior corrosion resistance.

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• Global Standard Compliance – Fully compatible with Metric (DIN) E Imperial (ASME B18.2.2) specifications for international machinery.

Technical Specifications

• Standards: DIN 557 (Standard) / DIN 562 (Thin) / ASME B18.2.2 (Square)

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• Metric Size Range: M2 to M24

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• Inch Size Range: 1/4" to 1-1/2" (UNC / UNF)

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• Property Class: Class 5, Class 8 / Stainless Steel A2-70, A4-80

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• Finish: Zinc Plated (Clear/Blue/Yellow), Black Oxide, Hot-Dip Galvanized, Plain

Material & Mechanical Properties

• Engineering Note: Select Grade 8 for high-vibration machinery; use A4 Stainless for chemical or marine exposure.

• Materiale	Grado	Tensile Strength	Feature	Applicazione
  Carbon Steel	Class 5	500 MPa	Ductile	General Hardware
  Carbon Steel	Class 8	800 MPa	High Strength	Automotive / Heavy Industry
  Acciaio inossidabile	A2 (304)	700 MPa	Corrosion Resistant	Food / Outdoor
  Acciaio inossidabile	A4 (316)	800 MPa	Acid Resistant	Marine / Chemical

Dimensions & Global Size Conversion

• Technical Standard: Longze provides precision four-sided square nuts manufactured to DIN 557 (Standard/Thick with chamfer), DIN 562 (Thin/Flat type), and ASME B18.2.2 standards. These nuts offer a greater surface contact area compared to hex nuts, making them ideal for high-vibration railway, electrical, and furniture applications where they can be held in place by a square slot or channel.

• American Size (# Gauge/Inch)	Nearest Metric Size (M)	Width Across Flats (s) (mm/inch)	Thick Height (m) [DIN 557]	Thin Height (m) [DIN 562]
  #6 - 32	M3.5	7.0 mm / 0.281"	2.8 mm / 0.110"	1.8 mm / 0.071"
  #8 - 32	M4	7.0 mm / 0.281"	3.2 mm / 0.126"	2.2 mm / 0.087"
  #10 - 24	M5	8.0 mm / 0.312"	4.0 mm / 0.157"	2.7 mm / 0.106"
  1/4" - 20	M6	10.0 mm / 0.437"	5.0 mm / 0.197"	3.2 mm / 0.126"
  5/16" - 18	M8	13.0 mm / 0.562"	6.5 mm / 0.256"	4.0 mm / 0.157"
  3/8" - 16	M10	17.0 (16) mm / 0.625"	8.0 mm / 0.315"	5.0 mm / 0.197"
  1/2" - 13	M12	19.0 (18) mm / 0.750"	10.0 mm / 0.394"	6.0 mm / 0.236"
  5/8" - 11	M16	24.0 mm / 1.000"	13.0 mm / 0.512"	8.0 mm / 0.315"
  3/4" - 10	M20	30.0 mm / 1.125"	16.0 mm / 0.630"	10.0 mm / 0.394"

Surface Treatment

• Procurement Guide: Match coating to the environment. HDG is recommended for utility poles; Zinc for interior panels.

• Coating	Process	Salt Spray	Ambiente
  Zinc Plated	Electroplating	72 - 144h	Indoor / Dry Storage
  HDG	Hot-Dip	500 - 1000h	Outdoor / Infrastructure
  Black Oxide	Chemical	24 - 48h	Decorative / Precision Tools
  Passivated	Chemical	1000h+	Marine / Medical (SS only)