Types Of Screw Heads
Screws are the most common form to connect two plates or any two pieces. Force is applied to the screw with the help of selected screw driver. There are many different types of screw head types.
- Slotted Screw Head
- Phillips Screw Head
- Pozidriv Screw Head
- TORX Screw Head
- TORX PLUS Screw Head
- TORX Tamper Resistant Screw Head
- Triangle – Recess Screw Head
- Square – recess / Robertson Screw Head
- Interior Hex Screw Head
- Exterior Hex Screw Head
- Multi – Tooth Screw Head
- Torq – Set Screw Head
- Tri – Wing Screw Head
- Spanner Screw Head
- Slotted Screw Head
This screw head is a simple and holds the tool blade by a line force. This is the first type of head screw and also the easiest type. The main concern is the lack of centering – which may slip out from the slides, making it not comfortable for mechanical applications.
Phillips Screw Head –
Phillips Screw Head is a crossed screw head type and can be represented as a double slotted screw head. This screw head has an advantage over slotted head screw which never slips from sideways. The force is applied from all the four edges which reduces the fatigue when turning the screw. A special surface coating is applied which reduces the cam out forces.
Pozidriv Screw Head –
This screw head consists of two crosses as a combination of two Phillips screw heads. These two profiles get fixed at 45 degrees to each other. This additional cross is for better stability and better resistance to slipping. It also has a surface coating which helps to reduce the cam out forces. The wrong handling of this screw head may lead to much damage and scratches.
TORX Screw Head –
This is a star shaped screw head. It has six shaped star inside it, made with six rounded lobes. This can be used to transfer high force than the three – screw mentioned above. The radial forces are very low which helps to increase the life span of both the screw and the screw driver. The major advantage is that there is no slip and the gripping is significantly strong.
TORX PLUS Screw Head –
This is similar to TORX screw head but the only difference is instead of sharp corners, it has rounded corners. This can guarantee maximum engagement with screw ad bit. This screw head can transfer more torque.
TORX Tamper Resistant Screw Head –
TORX Tamper Resistant screw head consists of a small hole located at the tip and this helps to prevent unauthorized tampering.
Triangle – Recess Screw Head –
It consists of a triangle shaped profiles and is mostly used by railways and fire brigades. These are very rare but familiar with railway employees for opening train doors and by fire brigades to unlock hydrants. This is not mostly used as much torque cannot be transferred.
Square – Recess Screw Head –
It consists of a square shape and is most commonly used in USA. These are used for electrical switches, mostly for vintage cars. The four corners are located at 90 degrees to each other. Even this is not effective for transferring more torque.
Interior Hex Screw Head –
This is most widely used and best known screw head having an interior hex. The name hex is for its hexagonal shape with six faces. This is not good enough for torque transmission as the stress concentration is very high.
Exterior Hex Screw Head –
This has the same properties as the interior hex screw head, but the hexagon is present to the outside. The rest is same as the Interior Hex.
Multi – Tooth Screw Head –
This profile has 12 small teeth. This is best when compared to others as the individual teeth are finer than combined. The large surface area enable this to transfer more torque, so widely used in automotive industries.
Torq – Set Screw Head –
This consists of four edges which shift asymmetrically to the center. This is designed and used exclusively by professionals as it a high match security profile.
Tri – Wing Screw Head –
This is same as Torq – Set profile but has three edges. Even this is a high security profile and used by professionals.
The spanner is also a high security profile with two rectangular shapes on the screw head. This is used for transmitting more torque with high stress concentration. Lower stress is applied on the individual faces.
These are the different types of screw heads.