Transit Visa For Nepalese Passport Holder

Hello,
Me and my wife are travelling to Australia to visit our daughter on December 25th
Our Itinerary is

Outbound
Flight From Kathmandu(KTM) Departs Friday, December 25, 2015 15:20
(1 hour stopover to Kunming same plane)
Arrives Shanghai Pu Dong(PVG) Friday, December 25, 2015 23:55

Layover At Shanghai - 22 hours

Flight From Shanghai Pu Dong(PVG) Departs Saturday, December 26, 2015 20:20
Arrives Sydney Kingsford Smith(SYD) Sunday, December 27, 2015 10:00

Inbound
From Sydney Kingsford Smith(SYD) Departs Tuesday, March 22, 2016 12:00
Arrives Shanghai Pu Dong(PVG) Tuesday, March 22, 2016 19:20

Layover At Shanghai - 14 hours

Flight From Shanghai Pu Dong(PVG) Departs Wednesday, March 23, 2016 09:00
Stopover at Kunming Same Plane (1 Hour)
Arrives Kathmandu(KTM) Wednesday, March 23, 2016 14:20

Now I have some queries
1. We have long layover time. So We want to get out from the airport and travel shanghai both the time (Outbound & Inbound). Can anyone please suggest us in details what are the procedure need to be done?
2. Do we need to apply for a transit type. Or Can we get out of the airport without transit type?
3. If transit permit applied once can work for both the time (inbound and outbound)??

I would be greatful.
Thank You