The difference between tower crane and self-erecting tower crane

Tower cranes can be divided into tower height-fixed type and self-erecting type. Self-erecting tower crane is a type of tower crane.
There are two main differences between tower height-fixed type and self-erecting crane:
1. Self-erecting tower crane has one more self-erecting section than height-fixed tower crane, which is used for self-erecting. They are all in the upper part of the tower crane and are larger than ordinary sections. It is easy to distinguish. When the tower crane is not high enough, it needs to be raised. The tower crane can use the hook to lift the standard section to be added to the self-erecting section, insert it, fix it, and then it will rise.
2. Self-erecting tower cranes are lifted and lowered by their own hydraulic devices. Non-self-erecting tower cranes rely on other lifting equipment such as hydraulic cranes for installation and disassembly.