Hull-based Martin Williams Ltd took over Penman Engineering near Dumfries in November last year.
The number of employees at the time had fallen to just 14 but the new owners said that now stood at 67.
Director Chris Williams said that if new work they hoped to secure did come in then numbers would rise further.
He said that would also leave them with the potential of a full order book for the next two years.
The site on the outskirts of Dumfries employed about 140 staff before it went into administration.
Mr Williams said they had completed their first stage of restructuring the company while managing to increase staffing levels.
He said they had concentrated on re-employing as many people as possible while building up orders.
"We have had massive support from Scottish Enterprise who have helped us from the day we took over and hold regular meetings with us to offer their support in a lot of different ways," he said.
"There are numerous different projects we are tendering for currently internationally and SE have also offered us support with this as well which is invaluable to us."
He said they had faced a number of challenges with suppliers who had lost money when the old company entered administration "understandably wary" of doing business with them.
"However, those who support the company will be rewarded in the future as bigger projects come off," he said.
"We will aim to put as much money back into the local economy and previous suppliers as possible to enable us to trade freely and have a good reputation in the future, the same as our existing company."
He said that overall he was positive about the direction the business was heading in.
"All in all things are looking good for the future," he said.
"It is still a tough climate and with Brexit you just don't know what's around the corner.
"But we are carrying on with what we know best which is to give the customer the best possible service and turnaround time that is also competitively priced."

Annie Woodland, 24, who lived in Essex, suffered brain damage in the incident at Gloucester Park Pool in Basildon.
A teacher and a pool life guard both failed to realise she was in trouble.
The family has successfully sued Essex County Council who said it did not comment on individual cases but had noted the High Court judgement.
The tragedy happened in July 2000 when Ms Woodland was a pupil at Whitmore Primary School in Basildon.
At an earlier hearing, judges ruled a victory against the county council would risk a "chilling effect" on the willingness of schools to take pupils on educational trips.
A Supreme Court judgement in 2013 overturned this ruling and opened the way for a High Court hearing.
Mr Justice Blake has now ruled lifeguard Debbie Maxwell and swimming teacher Paula Burlinson should have noticed Ms Woodland was drowning sooner than they did.
He concluded Essex County Council was liable for their negligence although neither woman was employed directly by the council.
Ms Burlinson's failure to notice Annie in distress "fell far below the standard of care reasonably to be expected of a teacher", he said.
Ms Maxwell was also negligent as "she was not paying sufficient attention to users in the water".
The amount of compensation to Ms Woodland, who now lives in Blackpool, will be assessed at a later date.
A spokesman said: "Essex County Council notes the judgement of Mr Justice Blake following a trial on liability.
"The authority cannot comment specifically on individual cases and it would be inappropriate to comment further therefore in respect of this claim."

Mr Eastwood is challenging current leader Alasdair McDonnell, and party activists will vote next month at the annual SDLP conference in Armagh.
Earlier this year, Mr Mallon called on Dr McDonnell to step down as leader.
Asked about Mr Mallon's endorsement of the Foyle MLA, Dr McDonnell said Mr Mallon was "entitled to his opinion".
"People have elected me to do a job and I'm going to do that job," he told BBC NI's The View programme.
"Seamus is a very distinguished member of the party, but we have some 300-odd other delegates out there with opinions.
"The majority have pledged their support to me."
Staffing levels could be set to double at a Scottish armoured vehicle business which was bought out of administration nearly six months ago.
[NEXT_CONCEPT]
A woman who nearly drowned during a school swimming lesson when she was 10 years old has won a compensation battle at the High Court.
[NEXT_CONCEPT]
Former SDLP deputy leader Seamus Mallon has endorsed Colum Eastwood in the party's leadership contest, the BBC has learned.