Mining Overcasts: Portal Frame, Purlin and Rated
GH Fabrications design and manufacture a full range of overcasts. All our overcasts were conceived with ease of transport, both to site and underground, and overall to simplify installation whilst keeping safety front of mind.
By using a larger RHS section in the panels, we have eliminated the need to use roof and wall braces, thereby minimizing risk to staff. Installation is faster and easier, simply lift the roof panels into place and drop the wall panels down and bolt in the predrilled holes. Airlocks can also be fitted to overcasts if required.
Portal Frame Overcasts
- Designed to be modular for easy transportation & installation.
- Two uprights connected across the top, with no wall or roof braces are necessary.
- Significantly reduced installation time
- Reduced safety risks associated with accessing the structure’s roof to install roof braces
- Roof panels are hinged to the wall panels allowing the positioning the roof panel into place and easily dropping the wall panels down into place
- Unrated, 2PSI rated and 5 PSI rated
- All rated designs are certified by GHF’s engineer
Unrated & Purlin Overcast
Our unrated purlin and iron overcasts have a simple and lightweight design.
Consisting of a C Purlin frame clad with corrugated iron and with adjustable legs are completely kitted with all the components necessary for easy installation.
Rated Sloped Sided Overcast
- Walls are set out or sloped
- Added benefit of additional room to pass under the overcast
- Significantly reduces the force of the air against the walls, allowing the air to flow up and over the angled walls with ease
Rated Splayed Overcast
- Designed for angled cut throughs
- Standard roof and wall panels
- End panels have been angled to suit roadway dimensions and angles
Unrated, 2PSI and 5PSI
Your mine’s ventilation design and the location of the device set the rating. Every rated design is certified by our engineer.
Calculators and quote builders
Free to use. Send the result to us for a quote when you’re ready.
Device quote builder
Build a list of airlocks, overcasts, regulators, doors and seals, and send it for a quote.
Open the toolDevice load calculator
Work out the load on a door or regulator opening from its size and design pressure.
Open the toolLeakage cost calculator
Put a yearly dollar figure on air leaking through stoppings, doors and regulators.
Open the toolRelated work
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What our clients say
“GH Fabrications have provided Tank Solutions a large and varied service for many years. Some of the products produced have been stairs, walkways and flyover systems on our largest tank projects.”
Tank Solutions
“GHF assisted us with a major steel fabrication project at the Cottage Creek site on Honeysuckle Drive, Newcastle. It was a complex job, however the final fabrication was delivered on time and is aesthetically very pleasing.”
Robson Civil
Request a quote
Send your drawings and we’ll come back with a price. No project is too large or too small. Call 02 4964 8270 or email sales@ghfabrications.com.au.