This is a metric grading similar to the sae grade 8 classification which is used in automotive and structural industries as well as in high temp applications.
Sae grade 8 socket head cap screws.
3 8 24 dia thread unf hex head grade 8 steel cap screws.
180 ksi tensile strength for fasteners up to 1 2 inch 170 ksi for larger sizes astm a574 p.
They are at least 25 stronger than medium strength steel screws.
High strength grade 8 steel hex head screws made from grade 8 steel these screws can be used in high stress applications such as valves pumps motors and automotive suspension systems.
The society of automotive engineers sae has set the standards for different grades of hex head cap screws according to their strength.
Steel grade sae 5 sae 8 socket head cap screws property class 8 8 10 9 12 9 socket head cap screw torque in pound foot or pound inch torque in newton meter nm lubed means cleaned dry bolts lubricated with standard medium viscosity machine oil.
High strength grade 8 steel hex head screws made from grade 8 steel these screws can be used in high stress applications such as valves pumps motors and automotive suspension systems.
Although grade nine is also sold and is assumed to be around 20 percent stronger than grade eight it isn t an sae grade and doesn t have standard chemical and physical.
1 1 4 7 dia thread unc hex head grade 8 steel cap screws with grade 8 steel construction these hex head cap screws offer high tensile strength and high torque capabilities.
Socket cap screws are commonly used in machine parts die fixturing and clamping.
Similar to a button head socket screw but with an 82 degree countersunk flat head.
Head height is 50 of a standard socket head and the socket size is smaller.
Similar thread design as a socket cap screw but the dome shaped head is wider and has a lower profile.
Socket head cap screws are commonly used in machine assembly for removable panels and parts.
For many more head markings and their corresponding specifications see here.
The socket head enables driving where there is not sufficient space for wrenches or sockets.
Metric plain and zinc plated hex and socket head cap screws 8 sae coated hex head and socket head cap screws mated with plain or zinc plated threads 9 sae coated hex head and socket head cap screws mated with coated threads 13 sae coated hex head flange screws.
The hexagon shaped heads are suitable for socket or wrench tightening.
The grades are two five and eight.
Socket head cap screws made from alloy steel are typically manufactured to a higher strength than sae grade 8.
Longer caps are easier to see when fastened while button and flat head caps are less likely to snag clothing or linkages.
