How long is the hexagonal bolt connection used for aluminum profile trolleys?

How long is the length of the hexagonal bolt connection bolt used for aluminum profile handcart? This question actually depends on which profile specification to choose. For example, if a 4040 profile is used and an internal hexagonal bolt specification of M8 * 45 is used, why did you choose this specification? The reason is selected based on the cross-sectional size of the profile, considering the connection strength of the two profiles, a 5mm size is set out to connect to the end face of the other profile. The bolt is connected to another profile by passing through the connected profile, which is 40mm in size. Additionally, it is necessary to allow two profiles to be connected, with an additional 5mm, which is exactly the size to be selected.

Here, we also need to use the upper half round head bolt, so do we need to choose the same specifications for half round head bolts as the hexagonal socket bolts? The answer is not!, The connection structure used by these two types of bolts is different. The use of hexagonal bolts requires passing through the profile, and the size of the profile needs to be taken into account. Therefore, the total length of the selected bolts should be much longer. Half round bolts are used to tap on the end face of the profile, slide the bolt head into the slot, and tighten it through the through hole at the position that needs to be fixed. The reason for this combination is to prevent cross blocking of the bolts in the connection of the three profiles.

The lengths of these two types of bolts can be customized, but they are generally 6MM, 10MM, 8MM, 12MM, 16MM, and even 45MM, which are also known as depths. The assembly of general frames requires the use of bolts.