1. It is designed for large manufactory
2. It is single boom structure
3. Luffing is stable

Port or harbour portal crane is used for loading and discharging cargos from ships or shipbuilding. It is suitable at various of ports and shipyards with the help of hook, hanger, grab, container spreader etc. 
Portal Jib crane is also called mobile slewing and luffing crane due to its working features.

the most important parameter is the lifting capacity and working radius.