Duct Insulation Nails, also known as insulation pins, duct fastening nails, or insulation hook nails, are specialized fasteners used to securely fix insulation materials (such as fiberglass wool, rock wool, rubber-plastic, etc.) onto various types of ducts (e.g., galvanized steel ducts, stainless steel ducts, composite ducts, etc.).

They are an indispensable auxiliary material in duct insulation construction.

​Main Types and Specifications​

1. ​By Fixing Method:

• ​Adhesive Type: The most common type, secured using high-strength adhesive. Suitable for metal ducts.
• ​Welded Type: Features a metal welding disk at the nail head, which is welded onto stainless steel or other ducts using a specialized welding machine. Ideal for large projects or applications with specific bonding requirements.
• ​Snap-on/Clip Type: The shank has barbs, and the washer contains a locking groove. Pressing the washer locks it in place quickly without tools.

1. ​By Length:

• The length (L) of insulation nails is primarily selected based on the thickness of the insulation layer. Common sizes include: 30mm, 50mm, 80mm, 100mm, 120mm, and 150mm.
• ​Selection Principle: Insulation nail length ≈ Insulation layer thickness + 10mm to 15mm (to allow space for washer installation and tightening).

​Key Features and Requirements​

• ​High Strength: The nail body and washer must possess sufficient mechanical strength to support the weight of the insulation material and withstand external impacts without breaking.
• ​Corrosion Resistance: Commonly used in HVAC ducts where condensation and high humidity are present, requiring materials to be corrosion-resistant, moisture-proof, and mold-proof.
• ​Low Thermal Conductivity: Made from non-metallic materials (e.g., nylon) to minimize thermal bridging and ensure effective insulation.
• ​Temperature Resistance: Must withstand temperature fluctuations in HVAC systems (typically stable within -40°C to +100°C).
• ​Strong Adhesion: Adhesive-type nails must be used with specialized glue to ensure they remain securely attached throughout the duct’s service life.

​Installation Guidelines and Notes​

1. ​Quantity Requirements: Standards specify the number of insulation nails per unit area:

   • ​Sides and bottom of ducts: At least 16 nails per square meter.
   • ​Top of ducts: At least 10 nails per square meter.
   • Adjust based on the density and specifications of the insulation material to prevent sagging.

2. ​Arrangement: Nails should be evenly distributed with spacing generally not exceeding 400mm. Nails near duct edges and flanges should be placed within 150mm of the edge.

3. ​Surface Preparation: Before installation, thoroughly clean the duct surface of oil, dust, and moisture to ensure a dry and clean bonding surface. Poor preparation reduces adhesion strength.

4. ​Adhesive Usage: Use only specialized adhesive for insulation nails; ordinary glue is not acceptable. After applying the adhesive, press the nail firmly for several seconds to ensure full contact.

5. ​Curing Time: Allow the adhesive to fully cure (typically 24 hours; refer to product instructions) before installing insulation materials and securing washers.