Mohawk Industries described some of the benefits ''likely to result'' from the sale as increased production, job creation and increased New Zealand-based wool processing and increased export receipts.
The Oamaru plant sits on 6.7ha of land and employed about 100 staff.
Etu union lead organiser for the southern region John Gardner said the onus was now on Mohawk Industries to deliver on its promise.
''With Mohawk being the company that they are, we trust they are going to use and expand production. The site has got the footprint that it could expand a lot. They have increased staff over recent times and hopefully this will secure the site a long way into the future. It really depends now on the new United States owners putting their money where their mouth is.''
Waitaki Mayor Gary Kircher said it was encouraging that Mohawk Industries had indicated it planned to grow the Oamaru site.
''It's great to see Mohawk have started they want to grow the company and increase production and employment. Those are real positive things for the Waitaki and Oamaru.''
The former Summit Woolspinners was sold to Canterbury Spinners in 2013.
About half of the then 192 staff were made redundant, but 61 were re-employed as Godfrey Hirst assessed the future prospects of the plant.
At the time the company cited a high exchange rate as a major contributing factor to its decision to sell.
