Pre-Curing / Vertical Curing Chamber / Sliding Curtains / Steam Boiler
Pre-Curing Chamber
Once the freshly poured concrete on the production pallet is Vibrated, Compacted & Well-leveled, the pallet is kept / passed through hardening chamber for accelerated curing to make freshly poured concrete to a semi-dry condition. To do so, elaborate piping is done on the floor of chamber and hot water or steam is passed through it. To reduce heat loss, insulation should be installed under the beds. The pipe for heating is above the insulation.
This accelerated curing is done so that it can be taken up for Trowelling for achieving excellent smooth surface of precast element and are then transported to custom-built Hardening chambers by vertical curing / individual pallet curing.
Economical solutions for pre-cure is by Covering the production pallet with a tarpaulin in order that the moisture is retained and there is no exposure to any dry winds.
Hardening or Curing chamber / Stacking in Storage rack Towers
The curing chamber is coupled with Temperature & humidity controller for curing. It consists of two / three vertical tower racks on left & right of pallet stacker. Each Rack tower has 6 to 14 pallet bays one above another, Depending upon the Height of plant & No of pallets to be cured in a circulating system the no of Bays, No of racks can be finalized. If requirement is high than it is done on both the side of pallet stacker.
For the storage and retrieval of the pallets, the rack doors are activated using a segmented door opener. The pallets are moved in and out by means of friction wheels and a pushing and pulling device.
Supporting Rollers adopt bolt connection method on steel frame structure of storage rack tower. Storage rack tower consist steam curing chamber, steam pumping system, temperature-controlling system. Used to cure the Precast elements for around 6 – 10 hours.
The pallets left covered for 6 to 10 hours in order to ensure that the minimum design strength of 15 N/mm2 is obtained. Once the final curing time has elapsed, the pallet with the desired precast concrete part is discharged to de-molding station for releasing it from the shuttering etc.