Portal cranes are mainly used for mechanized loading and unloading and reloading of ships and vehicles in ports and terminals, improving loading and unloading efficiency, and speeding up the turnover of ships and vehicles. This machine has four major mechanisms of lifting, luffing, rotating and cart operation. The four major mechanisms can be operated individually or in combination, which can reduce auxiliary time and improve work efficiency. It is a universal model with strong versatility, good flexibility and large working range. The machine can be equipped with hooks or grab buckets, and is suitable for loading and unloading various miscellaneous and bulk cargoes.