M18 x 220mm Socket Cap Head Screw, Self Colour, Grade 12.9 high tensile steel, DIN 912

M18 cap head screw

Socket cap head screw with a deep internal socket recess that allows easy installation and the application of the required torque for a secure hold.

A self-colour machine screw with a distinctive cylindrical head that’s designed to achieve high torque and manufactured from grade 12.9 high tensile steel for strength. 

Installed with an Allen wrench or hex key sees them widely used, including situations where space is tight and where a secure hold is needed every time.

Available in many sizes and lengths, these cap head machine screws are used by DIY enthusiasts and professionals across many diverse sectors. These include automotive, aerospace, machinery, and construction.

M18 socket cap head screw specification:

• Diameter (TD): M18 - 18mm
• Length (L): 220mm
• Thread length (TL): 48mm min
• Head width (HW): 27mm max
• Head height (HH): 18mm max
• Head type: Cap Head
• Recess type (DT): Internal hex drive (Size 14mm)
• Pitch: 2.5mm
• Material: Grade 12.9 high tensile steel
• Finish: Self-colour
• Conformity: DIN 912
  

Part of an extensive range of self colour socket cap head screws available from Fusion Fixings with bulk price discounts.

Don’t forget the self-colour hex nut!

If you need a self-colour hex nut to go with your self-colour socket cap head screw, take a look at our M18 self-colour full nut.

FAQs about self-colour cap head socket screws

What does “Grade 12.9” mean with socket cap head screw?

Grade 12.9 refers to a high-tensile steel strength class. It means the screw has an ultimate tensile strength of 1200 MPa (or approximately 175,000 psi) making it one of the strongest metric fasteners available.

Grade 12.9 is typically used in engineering, automotive, machinery and heavy-duty applications where maximum strength is required.

What is a “self-colour” finish?

“Self-colour” means the screw is supplied in its natural steel finish after heat treatment. The screws are sometimes lightly oiled or treated with a black oxide.

Are grade 12.9 socket cap screws corrosion-resistant?

No, these cap head screws are not corrosion resistant and the self-colour or black oxide finish gives limited resistance, making them not suitable for external conditions.

How is the length of the cap head screw measured?

The length of these screws is measured from under the head to the end of the thread, not including the head height.

Can I use grade 12.9 screws in high-temperature or vibrating applications?

Yes, these grade 12.9 screws are suitable for high operating temperatures and perform well in vibration-prone environments such as engines or machinery where they are widely used.