The company completed about 1.8m impressions last year on two Canon imagePress 7000VPs and a Canon imagePress C1.
According to print procurement manager Anthony Buck, that figure is likely to increase this year to between 3 and 4m.
He said there is a cost and time benefit to keeping smaller work in-house, while longer-run work that needs to be litho printed or needs a laminate finish is outsourced.
Buck said the reason behind the DocuMaster investment was that it offered a more professional finish for HGI's products.
He said: "It offered squareback finishing and that gave an extra look and feel of quality.
"We needed bookletmaking capability that would complement the quality of our print output, but this had to be linked to high productivity and the ability to take work from both our imagePress 7000VPs."
HGI's print department produces brochures, reports, newsletters and fact sheets.
Fund manager buys DocuMaster as output set to double

Fund manager Henderson Global Investors (HGI) has invested in a new DocuMaster from Morgana, in preparation for a potential doubling of its pressroom output.