call us: 84202 26655 / 79802 66981 / 90075 89008 (Indian Steel Corporation)
call us: 99881 12191 / 99887 76909 / 94287 01881 (Panama Syndicate, Ahmedabad Office)





Our Design Catalogue

Self Drilling Screws - Bright Zinc


Engineered to consistent performance and speed, Welfast Self Drilling Screws offer quality with precision. These are cold formed with rolled thread for superior strength and fast drilling performance. Strictly adhering to DIN Standards, Welfast Self Drilling Screws are available in a dynamic assembly of diameter ranging from #10 - #12 with length ranging from 20mm – 100mm. Additional options of Coarse Thread and Fine Thread adds value to selection.



  • High Performance – Continuous thread design up to drilling point maximizes pullout performance and shear strength.
  • Precision – Drilling these screws is achieved in a single process thus eliminating the need of alignment or pre-drilled holes and thus ensuring precision.
  • Easy and Smooth Tapping – Its smooth thread allows easy and self tapping through the structure.
  • Easy to Use with Minimal Efforts – Design of these screws is so engineered that unskilled amateur can use them with minimal efforts.
  • Time Saving – Using these screws saves time by eliminating the need of alignment or pre-drilled holes.
  • Dual Functionality – Allows fastening to both, timber and steel.
  • Minimal Wastage – Reduces Wastage

  • Roofing assembly
  • Brick Tie systems to metal studs
  • Decking to bar joist
  • Electrical boxes to metal studs
  • Light Gauge steel to structural steel
  • Masonry Ties to steel studs
  • Metal Building
  • Steel Channel to joists
  • Steel Frames
  • Stitching Deck Side Laps
  • Window Mullion to Steel Base

How to Install :

  • Insert the 8 or 10 mm (according to required size) hex head adapter into the drill motor. Center the adapter into the drill’s chuck to ensure that adaptor does not wander.
  • Put on the safety glasses to protect your eyes.
  • Inspect the hex end of the adaptor for cleanliness. If metal shavings are built up inside the tip, insert the drilling end of the screw into the cavity of the hex head while holding the trigger of the drill.
  • Place a self-drilling screw into the hex head adapter.
  • Depress the trigger of the drill slowly, while the drilling tip of the screw rests against the metal. Increase the speed of the drill when the screw finds its center.
  • Stop drilling when the head of the self drilling screw tightens against the surface of the metal. If the drill you are using does not have a clutch, pay close attention to the screw head, as too much pressure will either snap the screw of strip the threads formed in the metal by the screw.
  • Perform Step 3 before you install another self drilling screw.


Self Drilling Screw - #3
 
Self Drilling Screw - #4 & #5

Self Drilling Screw - #3 :

Hex Washer Head with Black Washer - Coarse Thread
Sr. No. Size (mm) Drill Point Drilling Capacity (mm) Pcs / Box Pcs / Carton
1 4.8 x 16 x 19 #3 3 600 2400
2 4.8 x 16 x 25 3 550 2200
3 5.5 x 14 x 25 4 500 2000
4 5.5 x 14 x 35 4 400 1600
5 5.5 x 14 x 45 5 350 1400
6 5.5 x 14 x 55 5 250 1000
7 5.5 x 14 x 62 5 200 800
8 5.5 x 14 x 68 5 200 800


Self Drilling Screw - #4 / #5 :
Hex Washer Head with Black Washer - Coarse Thread
Sr. No. Size (mm) Drill Point Drilling Capacity (mm) Pcs / Box Pcs / Carton
1 5.5 x 14 x 20 #4 5 500 2000
2 5.5 x 14 x 25 6 500 2000
3 5.5 x 14 x 35 400 1600
4 5.5 x 14 x 45 #5 8 350 1400
5 5.5 x 14 x 55 250 1000
6 5.5 x 14 x 62 200 800
7 5.5 x 14 x 68 200 800
8 5.5 x 14 x 75 150 600
9 5.5 x 14 x 90 150 600
10 5.5 x 14 x 100 100 400

INDIAN STEEL CORPORATION
Copyright © 2012-2023, Welfast Fasteners Pvt. Ltd. All rights reserved.