Hydraulic ram pumps and Sling Pumps

wooden-floatfinished. Before the second coat is prepared, the wall must be covered from the insidewith plastic sheeting to prevent it from drying out.Second Coat:The second coat differs from the first, as the sand must be passed through a screen sieve of 1.5mm, as required for ferro-cement. This process is described in Chapter 3. This coat should be aminimum of 5 mm thick, and wooden-float-finished. The working procedure is the same as that ofthe first coat. Before starting the second coat, the first coat must be wet, and the starting pointshould be changed so the meeting points of the first and second coats do not coincide.Third Coat:If the second coat can be applied in less than a day' the third coat can be applied when the secondcoat has been finished. The third coat is the 'nil coat' composition, as described in Chapter 3. As thethird coat is applied with a steel trowel, and is no thicker than 2 mm, it can be applied quite quickly.Remember the nil coat should be applied in one continuous process, and make sure enoughcement is prepared before starting. as the nil coat consumes about one 50 kg bag of cement perfive square metres. The nil coat should not cover the lower 100 mm of the wall, as the corner mustbe executed as shown in Figure 5.23.Floor screed mixture should be of the same composition as the first coat of plaster. After the screedis mixed, apply it to the corner with a glass bottle, as described in Chapter 5.1 and Figure 5.23. Thenil coat should be applied to the floor the following day, and two-three hours after finishing the nilcoat application, the floor should be covered with water for at least three days.When handling the formwork for the roof slab, make sure the floor is not damaged.6.2 Tendering a reinforced bricktankHow to use the information in this sectionIf a reinforced bricktank is to be tendered, the dimensions and amount of material required forbuilding it can be selected from Tables 8-14. This information can then be written in the relevantspace on the Bill of Quantities.This is not the place to explain the entire tendering process, but this brief information will assist youin reaching an agreement with a contractor. Tender documents should be given to at least threecontractors, in order to receive competitive prices. There are three different tendering documents:Conditions of Contract, Standard Specifications and Bill of Quantities After the documents havebeen completed by the contractors, they should be compared to ascertain the differences in prices.The cheapest contractor is not always the best, however, and workmanship demonstrated onprevious projects should be taken into consideration.Examples of the above-listed tendering documents follow.Contract ConditionsAfter the tender has been accepted, an agreement shall be made and entered into by and between(Name of Client)_____hereinafter called 'Employer' on the one part, and68