How do you determine the grade of a socket head cap screw?

How do you determine the grade of a socket head cap screw?

Socket head cap screws are not grade designated as are hex head cap screws. A standard inch series socket head cap screw is 20% stronger than a Grade 8 hex head cap screw and 50% stronger than a Grade 5 hex cap screw.

What do markings on bolt heads mean?

The markings can identify the standard to which the bolt was made. For instance, if a bolt head contains three radial lines, then it’s a Grade 5 bolt. If it contains five radial lines, then the bolt is Grade 8.

What are bolt grade markings?

The grade of a bolt determines the maximum amount of stress (tensile strength) that the bolt can handle. The SAE marking system uses raised dashes on the bolt head to indicate strength. Metric Bolt Grades—Metric grades are set according to rules set by the ISO (International Standards Organization).

How do you read a socket head screw?

Length is measured from the point at which the head sits flat with the surface, to the tip of the threads. Hex, pan, truss, button, socket cap, and round head screws are measured from right under the head to the end of the threads. Flat head screws are measured from the top of the head to the tip of the threads.

How do you determine the grade of a allen head bolt?

How to Determine the Hex Bolt Grade. Hex bolt grade refers to the grade of steel used in manufacturing the screw. This determines the amount of stress that can be applied to the fastener, known as “tensile strength.” The grade of a hex cap screw can be identified by markings on the head of the screw.

What does 8.8 on a bolt head mean?

So, in English, a PC 8.8 bolt is a bolt with a nominal tensile strength of 800 MPa and a nominal yield strength that is 80% of the bolt’s nominal tensile strength, or 640 MPa.

What size head is on a 7/16 bolt?

Hex Bolt Head Size Chart

Diameter Head Size
7/16″ 5/8″
1/2″ 3/4″
9/16″ 13/16″
5/8″ 15/16″

What grade is a bolt with 3 markings?

grade 5
Three radial lines will indicate an SAE grade 5 fastener, while six radial lines will indicate an SAE grade 8 fastener.