AvidSys acquired RCR Resources, RCR Power and RCR Water West.
The businesses will be renamed AVID Resources and will specialise in structural mechanical piping, electrical and instrumentation and water.
RCR general manager Andy Griffin and the current management team will continue to lead the business, which has 160 employees.
The business will soon move to a new head office in the Perth CBD and will be setting up its workshop facilities at a new site in the Industrial area near the Perth International Airport.
"With the support of AvidSys Group we can continue the outstanding work we have achieved for current clients and progress a range of new project opportunities," Griffin said.
"With our future secure and an owner who is not only financially and operationally committed to the business, its staff and clients, but who also has strong existing industry relationships, we are now well placed to expand our offering and grow the historical businesses under the AVID Resources brand."
AvidSys is an Indian-owned conglomerate with interests across multiple sectors, including resources where it counts BHP, Anglo American, Rio Tinto and Fortescue Metals Group among its clients.
"This transaction represented a strategic extension of our global strategy to provide vertically integrated end-to-end businesses as part of our wider group," AvidSys resources division chairman Ansh Gautam said.
"The RCR team is well regarded across Australia and I strongly believe that with financial and operational support from AvidSys they will continue to deliver high-quality production and services under the AVID Resources brand."