Reinforced Concrete Cement Pipes

2. Market Potential: Reinforced concrete cement pipes are used in the drainage system of urban areas, in rural and urban road construction, in the construction of buildings for different purposes, in irrigation and sewerage disposal projects. In short, they are major inputs in almost all types of civil engineering and building construction works. As mentioned in many other project ideas, these works have been expanding in the country during the last 5 to 10 years. This is manifested in the number of urban and rural roads water supply, drainage and sewerage and building works undertaken throughout the country. These cement pipes consuming engineering works have also be undertaken in the Amhara Region. Like many other construction material, cement pipes are transported from Addis Ababa to all construction sites in the Amhara Region. By the nature of their shape, cement pipes takes a lot of vehicle space when they are transported. It is a common sight along the major roads in the country to see one large truck carrying a small number of large pipes and moving them From Addis Ababa to construction sites hundreds of km. from Addis Ababa. This makes the pipes more expensive. However, if cement pipes are produced at least in the major urban centers of each Region, the pipes will be less expensive and this will stimulate the construction activities of the Region. More drainage, sewerage, irrigation and water supply systems will be built. Given the tempo of construction activities in the Amhara Region, establishing at least three modern reinforced concrete cement pipes making plants could be viable.

3. Source of raw material: Cement, sand and metal stone can be obtained from sources in the Region. Mild steel rods can be imported from Addis Ababa until the Region produces its own metal based construction materials.

4. Process and Technology: The first step is the preparation of reinforcement on a winding machine. Size of these rods depends on the size of the pipes to be made. Next, the reinforcement cage is placed inside the pipe mould which is then mounted on the trunnians horizontally. The mould is roated slowly and cement concrete mixture, prepared in a mechanical mixer by mixing one part of cement, 2.5 parts of stone metal and 2.5 parts of sand of proper size with the required quantity of water is fed from the open ends of the mould. After the required quantity of the concrete mixture has been fed, the mould speed is increased and after about 15 to 20 minutes, the inside of the pipe is smoothened with the help of a long rod which also throws out any excess water present inside. To produce additional finish of pipe from inside and reduce coefficient of friction, cement is sprinkled and mould rotated for some more time. Then the pipe mould is removed from the trunnian along with the concrete pipe and put in the curing place for one day and the mould is removed. The "green" pipe is rolled into a curing tank and allowed to remain standing in water for about 15 days. The cured pipe is tested for strength, porosity, dimensions, etc. on the basis of nationally accepted standards. Pipes below standards are rejected and considered as scraps. The list of machinery and equipment required for producing reinforced concrete cement pipes include pipe moulding machine complete with trunnions and driving arrangements, concrete mixer, reinforcement winding machine, lifting tackle rails with frame, etc. pipe and collar moulds and end rings, testing machine and other testing apparatus, etc.

5. Estimated Investment: For a plant which will produce 75 spun pipes of size 48 " X 4½" X 6 per day, the estimated investment will be as follows:-

Ø Buildings/shades 500 m² at Birr 1500/m²= Birr 750,000

Ø Machinery and equipment..................... = Birr 800,000

Ø Working capital..................................... = Birr 300,000

Total = Birr 1,850,000

6. Benefits: Promotes self-sufficiency in a key construction inputs, stimulates agricultural production through the development of irrigation.

7. Location: Bahir Dar, Combolcha, Gondar and sites of major civil engineering works.