We often receive calls from Contractors, Architects and Engineers wanting to play an active role in the design of a Unistrut Medical Equipment Support System. Since one of the most common applications is a Radiology (X-Ray) grid, we will discuss some design issues associated with these types of installations.
One design that we frequently see is adding structural steel beams (I Beams, or Wideflange Beams) perpendicular to the Unistrut, but just 3-1/4” above the ceiling (equal to the height of the P1001 ceiling channel). There are a few problems in doing this. We will address a few of them below.
- Design load: Most Radiology rooms are designed for a 1,000 lb load anywhere on the system (there are some that are higher and some lower, but this gives a basic idea for
topicof discussion). The ideal beam clamp to attach P1001 Unistrut to the beam is a P2786, rated for 2,000 lbs/pair, but unfortunately, these are wrap around style beam clamps,and would extend below the ceiling, something that is typically not acceptable. There are alternative clamps, but they do not have the same load rating.
- Deflection: Industry standards require system deflection to be below 1/16”. Spanning structural steel across a room, most likely around 15’ or so, will exceed the deflection requirements of the system.
- Steel tolerances: Most radiology systems have certain requirements for plumb and level. Because most structural steel is not fabricated to the tolerances that the equipment drawings require, chances are good that you are dealing with steel that is at least ¼” or ½” off over that span. Simply bolting P1001 below this does not fix the problem.
Now you may ask…….what do I do for our Unistrut system? We recommend having the structural steel several inches above the ceiling. Having the steel above the ceiling will allow the installation of additional Unistrut members, allowing infinite adjustment within the vertical members to get the system plumb and level. Contact the team at Unistrut Service Company for a quote on the design of your system today!