Space frames

"Ortz" system

General description
The ORTZ Structural System for the construction of spatial networks consists, basically, of two types of elements:  links and bars.

The link is a spherical piece, with a series of holes with threads depending on the direction of the bars, which must meet in it.  The possibilities, in terms of the bars' directions of access are practically limitless, except for the allowance to be made in order to maintain the minimum angle between two contiguous bars at which interference of one with the other is avoided.

The bars are tubular and welded onto each end they have conical caps with axial holes.  Specially designed screws fit through these caps.  These screws have two parts, threaded in opposite directions, separated by a conical truncated surface, which is what lies on the exterior of the spheres.  This two way thread allows double tightening with one single turn of the screw; the tightening of the sphere as well as that of the bar to the screw by the nuts situated on the body of the screw with the greatest diameter.  The main object of these two nuts is to act in the turning of the screw by means of a blocking system with a turning and back-turning effect.  Furthermore, however, in its final position this combination ensures constant tightness, avoiding the loosening of the joint by possible vibration.
This whole system allows the screw to retract towards the interior of the bar so that it may be assembled and disassembled without modifying the relative positions of the two spheres which it joins, even when they are in their definitive position.  This gives extraordinary flexibility in the process of setting up the network and facilitates the possible replacement of any damaged bar.

One of the objectives that have been set in this design is the achievement of a system with high axial rigidity, so that the discontinuity of performance which is inevitably caused in any screw joint, will be reduced to the minimum obtainable rates.  This has been achieved thanks to the special design of the screw and the use of a solid one-piece sphere.

Another of the aims achieved is a similar performance in both traction and compression alike, with good proportionality between load and strain within the workload.  This allows structural calculations to be made within the linear elastic field, maintaining great reliability of the results obtained.