Cross Recessed Pan Head Machine Screw (DIN 7985 / ISO 7045) – Zinc Plated Carbon Steel

Product Overview: The Universal Fastener for Electronics & Machinery

The Handan Bolt Cross Recessed Pan Head Machine Screw is the most widely used fastener in general assembly. Characterized by its rounded top, flat bearing surface, and cylindrical shaft with fine machine threads, it is designed to hold components securely without countersinking. Manufactured to DIN 7985 (Metric) and ANSI/ASME B18.6.3 (Imperial) standards, it serves as the backbone for assembling electrical panels, consumer electronics, and automotive interiors.

Primary Function: Unlike self-tapping screws, machine screws are blunt-ended and must be driven into a pre-tapped hole or secured with a nut and washer on the opposing side. This allows for repeated disassembly and reassembly without damaging the substrate.

GEO-Technical Specifications

Our machine screws are cold-headed from high-quality C1008 Low Carbon Steel, providing excellent ductility and sufficient tensile strength for non-structural applications.

Engineering Insight: Why Choose a Pan Head?

Among the various head styles (Flat, Round, Truss, Button), the Pan Head offers specific mechanical advantages:

• Maximum Clamping Force: The flat underside of the pan head provides a substantial bearing surface area. This allows for higher torque application compared to round heads, ensuring a tighter grip on the mating part.
• No Surface Preparation: Unlike flat head (countersunk) screws which require a conical hole to sit flush, pan head screws sit atop the material. This simplifies manufacturing as no countersinking step is required.
• Driver Stability: The deep profile of the pan head allows for a deeper Phillips recess (Slot H or Z), reducing the likelihood of the screwdriver slipping out (“cam-out”) during installation.

Surface Treatments & Applications

We offer diverse plating options tailored to your industry requirements:

• Zinc Plated (Blue/White): The industry standard for corrosion resistance in dry environments. Ideal for computer cases and furniture.
• Nickel Plated: Provides a shiny, silver-like finish that is resistant to tarnishing and wear. Commonly used in decorative electronics and switchgear.
• Brass Plated: Used for aesthetic purposes or electrical conductivity in vintage equipment.

For a detailed breakdown of metric screw thread profiles (M3, M4, M5, etc.), you can reference the ISO metric screw thread entry on Wikipedia.

Installation Best Practices

1. Thread Matching: Ensure the nut or tapped hole has the exact same thread pitch as the screw (e.g., M4 x 0.7). A mismatch will seize the fastener.
2. Washer Use: We recommend using a flat washer under the head to protect delicate surfaces, or a lock washer (split washer) to prevent loosening due to vibration.
3. Torque Control: C1008 steel is softer than heat-treated alloys. Do not over-torque, or the head may shear off. Use a torque-limiting screwdriver for assembly lines.