Telescopic boom and boom engineering machinery

The utility model provides a telescopic arm support and arm support type engineering machinery, and relates to the technical field of arm support type engineering machinery. The telescopic boom frame comprises a basic boom and a telescopic boom capable of stretching out and drawing back relative to the basic boom, a plug pin mechanism and a boom pin driven by the plug pin mechanism are installed on the basic boom, a locking plate is installed on the telescopic boom, locking holes are formed in the locking plate and comprise a plug pin hole and a working hole communicated with the plug pin hole, and the working hole is communicated with the plug pin hole. The bolt hole and the working hole are arranged along the telescopic direction of the telescopic arm, and the size of the bolt hole is larger than that of the working hole; and when the telescopic arm stretches out and draws back relative to the basic arm until the arm pin is aligned with the bolt hole, the bolt mechanism drives the arm pin to be inserted int