1. The quality requirements of opening holes on steel gratings

Under production, some steel gratings are requested to open holes due to various engineer project needs. For instance, pipeline construction for power plant boiler.

In general, the diameter of holes is larger than 200mm, it will be cut out at the steel grating factory; if the diameter is smaller than 200mm, we advice clients cut holes

on steel gratings at sites of a project according to specific situation, which can make sure to no lower the load capacity of gratings, resistant to corrosion, and also look tidy,

beautiful after installation.

2. Main construction process quality requirements of the opening

A. Holes Shape

There are two shapes of holes in steel gratings: round holes and square (oval) holes. As for tube bank, we cut square (circular) holes in steel gratings in principle,

but a single tube will be unified as circular or square holes.

B. Reference measurement

In the construction process, the actual reference data of measurement drawings affects the accuracy of the mounting dimensions of the steel grating directly,

so the reference point of opening holes is in keeping with control point of pipe installation. Besides, The actual outside diameter deviation of the measured pipe is plus

or minus 10 mm.

C. Line drawing

The engineer need to draw the specific place of opening holes in steel gratings according to reference points and drawing dimension, but thermal expansion of the pipe,

insulation allowance must be considered during drawing period.

D. Tapping

The workers cut steel gratings by cut machine instead of fire welding cutting to keep working face smooth and clean, and also easy for next step construction.

E. After opening

After cutting holes, the cut-outs will be banded with bearing bar to fixed steel gratings, which keep the whole grating strength and beautiful. Moreover, the banding bar must be same height with top and bottom of gratings.After banded, iron rust, residual welding spatter and other things should be cleared away.

F. Surface Treatment

All the process ends, the steel gratings will be galvanized or painted.

If you want to get more information, please feel free to contact with us.

contact person:Amber Wu

Phone/whatsapp: +86 18562239900

Email: amber@ythlss.com