Davies has named three vice-captains for the Japan tournament - Dragons academy and Ebbw Vale back row James Thomas, Ospreys academy and Aberavon back row Justin Tipuric - who both wore the captain's armband at times during the recent Six Nations campaign - and Ospreys and Aberavon centre Ashley Beck, who was vice-captain for much of that championship. Tipuric is the other member of the squad who was part of Wales' Junior World Championship side last season.
Five uncapped players will travel to Japan next month for the IRB's under 20 tournament - Llanelli full back Daniel Newton, Carmarthen Quins duo Jamie Davies and Jason Harries, and two players whose fathers played international rugby for Wales - Blues academy and Glamorgan Wanderers scrum half Lloyd Williams (son of former Wales and Lions scrum half Brynmor) and Llandovery prop Owen Evans (son of former Wales prop Ricky).
Phil Davies said: "We are all very excited about this tournament and the prospect of playing against new opposition in a world cup environment over a three-week period.
"We have been together as a squad for a sustained period of time now and we are determined to build on our Six Nations performances. We are clearly aiming to win as many games as possible but, whatever happens, the experience of training and playing in a near professional environment is guaranteed to help develop these players towards their full potential, standing them in good stead for the future.
"We are extremely pleased with the level of strength in depth that has been developed in terms of the leadership of the group, and Scott Andrews has shown himself to be a natural leader. The vice-captains will also have a key role to play on and off the field.
"Seven players not named in our initial Six Nations squad have forced their way into this Junior World Championship group. There have been some injuries and changes in form but all those included have certainly earned their place.
"Jamie Davies and Jason Harries were recommended to us through our clubs and scouting system and they, along with Owen Evans, have been training with us since before the Ireland fixture, impressing in our Development XV game against Japan earlier this month. Lloyd Williams has been recovering from injury for most of the season but has come back to fitness and form at the right time, showing a renewed sharpness in his club performances of late.
Wales Junior World Championship squad:
James Leadbeater (Cross Keys), Daniel Newton (Llanelli), Nick Reynolds (Llanelli), James Loxton (Blues academy /Glamorgan Wanderers), Jamie Davies (Carmarthen Quins), Ashley Beck (Ospreys / Aberavon), Scott Williams (Scarlets academy / Llanelli), Jason Harries (Carmarthen Quins), Dai Langdon (Dragons academy / Ebbw Vale), Matthew Jarvis (Ospreys academy / Neath), Tavis Knoyle (Neath), Lloyd Williams (Blues academy / Glamorgan Wanderers).
Scott Andrews (Blues academy/ Glamorgan Wanderers), Aaron Coundley (Dragons academy/ Ebbw Vale), Simon Gardiner (Scarlets Academy / Llanelli), Owen Evans (Llandovery), Rhys Williams (Blues academy / Pontypridd), Craig Attwell (Dragons academy / Newbridge), James King (Ospreys academy/ Aberavon), Ashley Sweet (Dragons academy/ Cross Keys), Dan Partridge (Beddau), Justin Tipuric (Ospreys academy / Aberavon), Josh Navidi (Blues academy / Glamorgan Wanderers), Rory Pitman (Ospreys academy/Bridgend), James Thomas (Dragons academy /Ebbw Vale), Rhys Jenkins (Dragons academy / Ebbw Vale)