Premium Square Nuts: The Secure Solution for Channels and Blind Spots
At Handan Bolt, we manufacture a comprehensive range of Square Nuts (Four-Sided Nuts). Produced in our specialized facility in Yongnian, China, these fasteners are designed for specific applications where standard hex nuts simply won’t work. We supply millions of DIN 557 and DIN 562 nuts annually to the construction, electrical, and furniture industries, offering both Metric and Imperial specifications.
What is a Square Nut?
A Square Nut (Read more on Wikipedia) is a four-sided nut that was the industry standard before hexagonal nuts became dominant. Today, they are prized for their specific mechanical advantages:
- Greater Surface Area: The square shape provides more contact area with the part being fastened compared to a hex nut. This offers greater resistance to loosening and “rounding off.”
- Blind Installation: Square nuts are designed to sit in a square channel or groove. When the bolt is tightened, the channel walls prevent the nut from turning, allowing for easy one-handed tightening.
- Aesthetic Appeal: They are frequently used in rustic furniture and antique machinery restoration for their classic look.
Standards Breakdown: DIN 557 vs. DIN 562
We manufacture both types mentioned in your specifications to suit different needs:
1. DIN 557 (Square Nuts with Chamfer)
This is the “Standard” or heavy-duty version.
- Design: Features a chamfered (rounded) top edge and a flat washer face on the bottom.
- Application: General construction and heavy machinery. The chamfer allows for easier automated feeding in assembly lines.
2. DIN 562 (Square Thin Nuts)
Also known as a Plate Nut.
- Design: Much thinner than DIN 557 and typically flat on both sides (no chamfer).
- Application: Used in electronics (PCB mounting), thin sheet metal assemblies, and tight spaces where a full-height nut won’t fit.
3. ASTM A563 (US Standard)
For the North American market, we produce Grade A Square Nuts often used with square head bolts for utility pole line hardware.
Material Grades and Strength
Square nuts are versatile, and we offer grades to match your bolt strength:
- Grade 4 / 5 (Mild Steel): The most common grade for DIN 562 thin nuts and general furniture assembly.
- Grade 6 / 8 (High Tensile): Used for DIN 557 nuts in structural applications (Strut Channels) where higher clamping force is needed.
- ASTM A563 Grade A: Standard carbon steel grade for US construction projects.
Surface Finishes: Corrosion Resistance
We offer finishes tailored to the nut’s final environment:
- Zinc Plated (Clear/Blue): The standard finish for indoor use. It provides a clean, bright look and basic rust protection.
- Hot Dip Galvanized (HDG): As mentioned in your product specs, we specialize in HDG square nuts. These are essential for outdoor Strut Channel systems and utility poles, providing decades of protection against rain and snow.
- Plain / Oil: Often requested for antique furniture restoration where a raw steel look is desired.
Common Applications
You will find our Square Nuts in:
- Strut Channels (Unistrut): They slide into the channel track and lock in place.
- Railways: Rail joints often utilize square nuts for their vibration resistance.
- Electronics: Battery terminals and circuit board spacers.
- Furniture: “Mission Style” or “Arts and Crafts” furniture pieces often use exposed square nuts for decoration.
Why Source from Handan Bolt?
Perfect Fit: We ensure precise dimensional tolerances so our nuts slide smoothly into standard channels (like 41×41 strut) without jamming.
Large Tapping Capacity: Our automated tapping machines ensure clean, burr-free threads for fast assembly.
Flexible Packaging: From small 100-piece boxes for hardware stores to bulk kegs for industrial use.
Get a Direct Factory Quote
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