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Attaching Fittings to HSS Tubing With Lindapter Hollo-Bolt

The first rule of construction is to expect the unexpected.  When unforeseen consequences threaten the successful completion of a project, versatile building materials like Unistrut start to shine.  The very nature of the Unistrut system allows for quick and easy, in-the-field adaptations to design concepts –changes that can save the day.  Our team of installers recently used Unistrut channel and Lindapter Hollo-Bolts to save the day during the tail end of a heater installation at a local, nationally known wildlife park.

The contractors on this job consulted us to discuss problems associated with overhead heater units and a roll-up style garage door.  The architect’s drawings specified placing the heaters too close to the door.  When the door was in the open position, the seals began to melt, and the units struggled to heat the structure.  Our job was finding a non-intrusive way to re-position the heaters to increase heating efficiency and prevent further damage to the door seals. Our challenge was finding a means of attaching angled Unistrut P1326 fittings to painted Hollow Structural Section (HSS) square tubing.  One of the best-suited fasteners for this type of application is Lindapter’s Hollo-Bolt®.

Lindapter Hollo-Bolt Features

How Lindapter’s Hollo-Bolt® Works

The Hollo-Bolt® allows for a “blind connection” technique that requires installation access to only one side of the steel tubing. A Hollo-Bolt® connection is created by inserting the fastener into pre-drilled holes and tightening with a torque wrench.  While tightening, the cone travels up the bolt thread, expanding the sleeve legs and locking them against the hollow section’s inner wall.  To learn more about Lindapter Hollo-Bolt, download our data sheet which is available in PDF format.

Lindapter Hollo-Bolt Fastener System

This attachment method helped the contractor avoid welding new mounting fittings to re-position the heaters.

Lindapter Installation

Even the best-laid plans can take a detour when architectural drawings do not take into consideration how HVAC and plumbing systems fit with the overall design concept.  One of the best solutions for these types of situations is Unistrut.  Sometimes in the field, modification of structural steel is unavoidable.  That said, if you can eliminate additional fabrication steps such as cutting and welding by using Unistrut, you can get your project back on track and budget more quickly than you might think. Do you have a vexing design problem or a roadblock that is slowing down completion of your project?  If this is the case, contact the friendly staff at Unistrut Service Company, and we'll gladly lend a hand.