The 19 stone prop has signed a deal with the region for three years and will join them in the summer during preseason. The tight head is Welsh qualified through his mother who is originally from Blaenavon.
The 22-year-old, who currently plays for the Exeter Chiefs, has also made appearances for Moseley, Cornish Pirates and Plymouth Albion.
Newport Gwent Dragons director of rugby, Lyn Jones commented, "I am delighted that Lloyd has signed a contract with us.
"He has shown great promise through learning his trade with Exeter. The key part with him is his development; I want to spend time continuing the good work that Exeter has done with him, making Lloyd the best that he can be.
"He has outstanding ability and I look forward watching him develop as a player in the Dragons squad."
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