The 34-year-old outside back has signed a one-year deal with the club after leaving Featherstone Rovers, having previously enjoyed a glittering career in Super League with Salford Red Devils and Hull KR.
Hull-based Welham represented Salford in the 2019 Super League Grand Final and the Challenge Cup Final the following year and played in the Million Pound Game just last month.
These days he balances his rugby commitments with a career in pest control, working for his father-in-law and former Sheffield Eagles coach Gary Wilkinson, who himself worked alongside Aston at the club.
"It’s different,” Welham said of his new role outside of the sport.
"I enjoy it, every job is different, meeting new people with different stories. Rugby doesn’t last forever, you have got to make that transition at some point and get a real job.
"It was a bit of a shock working all day then going to training, getting home late then you are back at work the next morning. As a full-time player you don’t understand what part-time players go through.”
Still, Welham is planning to himself be a thorn in the side for Championship defences and difficult to catch next season, which begins on Sunday, 30 January.
He said: “I don’t know when the end is going to be, I know it’s close. This could be my last year, I want to do my bit this year and try and win something.
"The squad is really good, the boys are a good laugh and love to work hard.”
As well as his playing pedigree, Welham has been recruited to help lead the Eagles dressing room following a disappointing 2021 campaign which saw them finish third from bottom.
In contrast, the Colliers won 22 of their 24 matches in the second tier and picked up the 1895 Trophy.
But Welham said: "I know what I have signed up for, we played Sheffield twice last year. They started really well. They have got the potential in the squad to really do something, if they wanted to.
"I’ll be trying to instil that positivity in the boys and do my bit to earn a few more wins.”