Butler, Tanner & Dennis

A new print finishing and book binding extension built by printers Butler and Tanner at its Selwood printing works in Frome, Somerset houses three lines of binding machines in an area totalling almost 7,000m2 (including a loading bay). Because fumes from the glue used to bind the printed pages needs to be rapidly removed from each machine, the facility’s heating system had to be capable of implementing regular air changes with warm or conditioned air, depending upon the seasonal requirements.

 

Furthermore, this had to be accomplished without disturbance to printed paper stocks while delicate and stable temperature control was essential to the proper management of large volumes of paper and print materials.

 

Air Mixing, the ducted air distribution system from Reznor UK, was selected for its versatility in dealing with the specific heating and ventilating requirements in the bindery. In phase 1 of the project, warm or conditioned air is introduced through steam-heated air handling units and along a total of 180 metres of Air Mixing perforated duct work. The air passes at high speed along the duct work to induce a negative pressure zone around each calibrated perforation resulting in a high level of entrainment. Manufactured from lightweight, fibreglass-reinforced PVC in a wide choice of colours, Air Mixing duct work is designed and manufactured to specification for each application and does not add any appreciable weight to the building structure. Phase 2 of the project involved the installation of a 90 metre duct to provide air conditioning to offset heat gain from a newly-built printing line.

 

Operationally, the Air Mixing system is designed to achieve fourteen air changes an hour to maintain optimum air quality in the bindery while producing a universally even temperature which varies by only 1°C between the air handling unit and the end of the duct. Air movement is achieved without the turbulence and preferential air currents typical of conventional air distribution systems.

 

No machinery shut-down was required during the installation at Butler and Tanner and, as the ducting deflates when not in use, maintenance and cleaning is simply undertaken. In all, Air Mixing is estimated to have cost about £10,000 less to install than a conventional galvanised ducting system which, with the grills and painting required, would also have taken longer to fit.