Product Overview
The 3.5-5.5mm Black Phosphated Drywall Screw is specialized for gypsum board installations. Made of 1022 carbon steel (0.20-0.25% carbon) with 5-8μm black phosphate coating (enhances corrosion resistance/mud adhesion). Features #2 Phillips bugle head (90° countersink) and 18 TPI fine thread. Lengths: 25mm (12mm gypsum), 35mm (15mm), 50mm (12+12mm double-layer), 75mm (gypsum+20mm insulation). Modified thread root (0.3mm radius) reduces wood splitting. Passes 200-hour salt spray test (ASTM B117) and meets ASTM C1002; shear strength: 800N (0.6mm Q235 steel studs), 650N (18mm pine plywood).
Scenario-Based Solutions
Residential Drywall Installations
Withstands 30-80% RH and -10℃ to 50℃ in bedrooms/bathrooms/kitchens. Secures moisture-resistant gypsum (green board) to 0.8mm steel studs (no paint shadowing) and fire-resistant gypsum (purple board) to pine joists (200mm spacing). Resists mold/rust in basements for 10+ years.
Commercial Construction Projects
Self-drilling HSS tip (30° taper) eliminates pre-drilling, cutting installation time by 20%. Secures 12mm gypsum to 1.0mm aluminum studs (offices) and metal tracks (retail partitions). Flush design ensures sanitization in hospitals; resists disinfectant corrosion.
Fire-Rated & Renovation Projects
Complies with ASTM E119 (1 hour at 980℃) for school/hospital fire partitions. Fastens new gypsum to old oak joists or 0.7mm rusted steel studs in renovations.
Core Features
Enhanced Mud Adhesion
Porous phosphate coating (Ra 1.6-3.2μm) boosts mud bond by 30% vs. zinc-plated screws. Mud penetrates pores, eliminating post-paint fastener shadows.
Self-Drilling Efficiency
30° tip pierces gypsum and ≤0.8mm steel studs without pre-drilling. Reduces resistance by 25%; drivable with 12V screwdriver (1500 RPM) for 1000㎡ offices (2-3 days).
Multi-Material Compatibility
Works with 0.5-1.0mm metal studs and 15-30mm wood joists, cutting inventory by 40%. Fine thread (≥5 turns) resists loosening on metal; modified root prevents wood splitting.
Reduced Driving Torque
Phosphate coating acts as lubricant, reducing torque by 15% (3-5N·m for 4.2×35mm screws). Prevents cam-out and extends tool life.
Customization Services
Size & Thread Customization
Adjusts diameter (3.5-5.5mm) and length (80-100mm for ceiling insulation). Offers 3.5mm flexible-shank screws (0.20% carbon) for curved walls; adjusts thread pitch (16 TPI soft gypsum, 20 TPI dense gypsum).
Coating & Material Customization
Provides black phosphate + epoxy coating (500-hour salt spray) for ≥85% RH areas (swimming pools) and color-matched phosphate (gray/black/brown) for theater gypsum. Uses 1018 steel (DIY) or 10B21 steel (≥600MPa, commercial).
Batch & Packaging Customization
Offers 10,000-100,000pcs bulk batches (scheduled deliveries) and 100-500pcs retail boxes (clear windows/blister packs with multilingual guides). Brands packaging with client logos; expedites orders in 5-7 days.
Product Video
