Flat Head Self-Drilling Screw with Wings Manufacturer

Overview

For fixing timber or fibre-cement board to steel. The wings ream the wood slightly larger than the thread so the board is pulled tight, then break off when they hit the steel and the thread engages.

A ribbed countersunk head self-embeds for a flush finish.

Applications

Timber decking on steel joists
Plywood floors on steel
Trailer and truck beds

Used in these projects

Hardwood decking and timber structures

Key features

Wings prevent jacking of the timber
Ribs under head self-countersink
Fixes wood to steel in one pass
Up to 12.5 mm steel with #5 point

Specifications

Typical values. Every dimension, hardness and coating is confirmed in writing with your quotation.

Flat Head Self-Drilling Screw with Wings specifications
Standard	DIN 7504 P/O
Diameter	ST4.2, ST4.8, ST5.5
Length	25–100 mm
Material	Carbon steel
Head	Flat countersunk, ribbed
Drive	Phillips, star
Finish	Zinc, black, ceramic
MOQ	5,000 pcs
HS code	7318.14 / 7318.12 (by type)

Buying guide

Applies to all self-drilling screws.

Match the drill point to the steel

Point #1 suits sheet up to 0.9 mm, #2 up to 2.8 mm, #3 up to 4.4 mm, #4 up to 5.25 mm and #5 up to 12.5 mm. The drill flute must clear the full material thickness before the thread engages, or the screw will jam and snap.

Choose a washer for weather-tight joints

Roofing and cladding screws take a bonded EPDM washer (14, 16 or 19 mm) under an indented hex washer head. The rubber seals the hole; the steel backing spreads the load so the sheet does not dimple.

Specify corrosion class, not just "zinc"

Electro-zinc gives roughly 72 h to white rust in salt spray. For exterior roofing ask for ceramic coating (500–1,000 h) or AS 3566 Class 3/4 coatings, and for coastal sites move to bi-metal stainless screws.

Ordering

Packing and delivery

Standard terms for this product. Tell us if your market needs something different.

PackingSmall boxes, buckets or 20–25 kg cartons on fumigated pallets; private label available.

Lead timeSamples in 7 days; production 25–35 days after deposit.

PaymentT/T 30 % deposit, 70 % against B/L copy, or L/C at sight.

ShippingFOB Shanghai or Ningbo, CFR or CIF to your port.

Questions about this product

What is the difference between self-drilling and self-tapping screws?

A self-tapping screw forms threads in a pre-drilled hole, while a self-drilling screw drills its own hole first using a drill-shaped point. Self-drilling screws save a step on metal-to-metal joints.

Which standards do your self-drilling screws follow?

We produce to DIN 7504 (K, M, N, P, O forms), ISO 15480–15483 and AS 3566.1/.2, and to customer drawings for non-standard lengths, heads or head marks.

What is your MOQ for self-drilling screws?

Standard sizes start at about 500 kg or 50,000 pieces per size. Mixed sizes can share one container, and stock items can ship in smaller lots.

Self-Drilling Screws