Rectangular Steel Tube for Solar Mounting – RHS Hollow Section

Why Rectangular Steel Tube for Solar Mounting?

The physics is simple: bending resistance comes from steel placed far from the neutral axis. A closed rectangular section keeps its material at the outer fibres, so for the same weight per metre it delivers a higher section modulus than a C channel, Z purlin or equal angle. That is the core reason EPC contractors and distributors keep specifying RHS.

Three further advantages make it the engineering favourite:

• Doubly symmetric section.

  The shear centre coincides with the centroid, so loads applied at the face of the tube do not create the torsional eccentricity that plagues open profiles. C and Z sections twist under load unless restrained — a failure mode you rarely see in RHS.

• Superior torsional stiffness.

  A closed box has far higher polar moment of inertia than an open channel of the same weight. Long purlins under wind uplift or unbalanced snow load experience real torsion; here the rectangular tube behaves dramatically better.

• Clean, flat surfaces for connections.

  Rail brackets, clamps and bolts seat flush against the tube face, which speeds up installation and simplifies structural analysis.

ZAM Rectangular Pipe for Solar Structures: Corrosion Protection That Lasts

Solar assets are designed for 25+ years outdoors, so surface protection is not optional — it is structural. Zinc‑Aluminium‑Magnesium (ZAM) rectangular pipe is the premium solution for solar structures:
ZAM coated sections deliver superior long‑term corrosion performance, with built‑in cut‑edge self‑healing protection, outperforming conventional hot‑dip galvanized (HDG) material for harsh outdoor environments.
Cut ends and welds should be repaired with zinc‑rich paint to maintain continuous galvanic barrier performance.
One practical detail: because RHS is a closed section, always specify weep/drain holes (or leave specified ends unsealed) so internal condensation can escape. Combined with ZAM coating protection on the inner surface, this delivers maintenance‑free service life matching the PV plant’s design asset life.

Rectangular Tube Solar Ground Mount: Why Designers Choose It

In ground-mount engineering, the dominant loads are wind uplift, wind torsion and uneven snow. That is exactly the load spectrum where closed sections win:

• Wind uplift

  puts purlins in negative bending and torsion — RHS resists both without added bracing.

• Long spans between piles

  let you cut foundation count, and rectangular tube solar ground mount structures make that possible with modest section sizes.

• Angle adjustability

  at beam-to-post connections allows tilt optimization per site without custom fabrication.

A common configuration: driven piles or concrete footings → two or three rows of RHS stringer beams → RHS purlins → module rails → modules. Fixed-tilt ground mounts and the support frames of single-axis trackers both rely on RHS; the rotating torque tube itself is normally a round hollow section, while everything that carries it is rectangular steel tube.

How to Specify Rectangular Steel Tube for Solar Mounting

To get an accurate quote in one round, send your supplier this checklist to us:

1. Size and wall thickness (B × D × t), e.g. 80 × 40 × 3.0 mm
2. Lengths and quantities (per BOM or drawing)
3. Pre-punching / cutting drawings (PDF, DXF or DWG)
4. Destination port (for freight and lead-time calculation)