Hydraulic ram pumps and Sling Pumps

figure 5.23After you have shaped the corner remove the rest of the plaster carefully from the floor. Working insteps of about 2 m, move round the tank until you reach the starting point. From here you startagain, this time with the nil coat. If the plaster is still too wet, wait for a while. This is an importantoperation and has to be done very carefully, since this part of the tank sometimes leaks. After thecorner all around the tank is neatly shaped and covered with nil coat, pour water onto the floor slab.The nil coat for the floor is not to be done before the roof is finished.5.1.8 Preparing the roof reinforcementTurn the prepared reinforcement of the roof over and start covering it from the inside with cloth. Youmust sew the cloth (sisal, jute or nylon, as for the wall) to the reinforcement. It is imperative that thecloth remains in the same shape as the dome when you turn the roof back over into the normalposition, Fig. 5.24. Move the roof onto the tank and put it in position, then tie it in this position usingthe former vertical ends of the reinforcement mesh, as well as with binding wire using pliers. Afterthe roof reinforcement is secured onto the wall, cut out a 450/450-mm manhole using a hacksaw.Trim off all excess wires from the roof reinforcement. Examine from inside the tank. Where clothforms a sag, sew it back to the reinforcement. Support and prop up the roof from inside with poles,starting in the centre. Now mark the place (or places) where the downpipe from the roof will be fittedinto the tank. This remains an opening. Start plastering and use the same mixture as you used forthe wall, keeping it slightly wet. If the mixture falls through the wire it is too wet. After the roof is42