1. Mechanical Fasteners- Bolts & Screws

2. Definition
A mechanical fastener is a means of retaining something tightly and permanently using a specified method
This may come in the form of securing one item such as a door, to a frame
The range of methods used to achieve this include bolts, screws, nuts, rivets, pins, clips, studs, washers, adhesives, wire and keys
Each of these is used across a range of methods and requirements
These are used to provide a permanent fixing for their own requirement

3. Bolts
These come in different configurations to suit a range of requirements
The thread amount on the shank can vary, depending upon the needed strength or the range of tightening required
The head shape also require to be different depending upon the need

4. Fixing a Nut and Bolt Together
As you probably already know, a bolt is fastened in place by rotating clockwise to do up / fasten and anticlockwise to undo / loosen by rotating anticlockwise.
A bolt can be either fixed directly into a threaded hole or passed through a plain clearance hole & fastened on the other side of it by tightening the nut.

5. Bolt

6. Set Bolt / Screw

7. Bolt with Plain Shank

8. Grub Screw

9. Cap Headed Screw

10. Counter Sunk Head Screw

11. Stud

12. Other Screw Types

13. Hex Bolt Identification Markings & Strength Chart
Scroll down the first page telling firstly of the top yellow title block & its meaning
Focus on the specification & the grades which will be found on the heads of hex bolts
(8.8 being the most commonly found)

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What mechanical fasteners do we find in this room?