Shrink Tunnel Integrates Compact Steam Boiler

Highlighted at the show, PDC International Corp.’s new steam shrink tunnel, the KST 55-712, includes an integrated compact steam boiler that provides a plumbed and complete steam tunnel system, eliminating the need to install a separate costly and remote boiler.

The KST 55-712 is a single-zone system with five rows of steam distribution tubes on both sides of each zone for a total of 10 steam runs. There is a pre-shrink zone at the entry to the tunnel to anchor sleeves at the base of containers. Each run is externally adjustable for steam flow and rotary position so adjustments can be made without waiting for the tunnel to cool.

Explained PDC, steam regulation is key to consistency in shrinking, so the system precisely regulates steam flow in five distinct ways: step-down regulators, condensate traps, steam filtering, a proprietary steam valve, and optional electronic regulation. Each tunnel includes a stainless-steel vent manifold with adjustable dampers to closely regulate the steam exhaust drawn from the tunnel. The electronic regulator developed by PDC monitors tunnel temperatures in real time and makes continuous adjustments in steam release to compensate for the “thermal loads” of incoming product. According to PDC, this is particularly useful when the system is running full or cold containers.

The KST 55 steam tunnel has a stainless, dual-wall construction and opening dimensions of 7 in. W x 12 in. H. It is compatible with a range of containers and operates at speeds to 100/min. Containers can be filled or empty, and virtually any shape, including oval or square.It can also uniformly shrink a range of films, including polyvinyl chloride, PETG, oriented polystyrene, and polylactic acid.

The system mounts over existing conveyors, or PDC can provide conveyors specifically constructed for use in steam. Options include a heated shroud that shields the top of the empty containers inside the tunnel, a condensate diverter package, a culinary-grade steam filter that purifies incoming steam, and a vent blower stand with a variable frequency drive.

Shared PDC, as with all its steam tunnels, the KST 55 is manufactured in the USA using high-quality stainless steel and standard, readily-available components.