The machine will run alongside a BQ270 perfect binder and will enable the department to keep up with its extensive press division.
Five-staff DPI runs three Xerox 4127 presses and a Xerox 700, which it installed in June last year.
Managing director Robert Jupp said: "We were seeing a major bottleneck with four digital presses churning out manuals for the BQ270 to perfect bind because we had to three-knife trim them on a guillotine.
"It was causing us a delay, but the HT30 has already turned out a full day's book trimming in just a couple of hours."
The Dorset-based company, which has a turnover of around £300,000, has been upping its colour work in recent years. It handles a wide range of commercial work.