DripTech Irrigation (Pvt) Ltd was established in 1995 in Harare and they still have their head office in Workington, although they have grown and expanded to include a number of other branches in Harare and Mutare. They recently opened their newest branch on Harare Drive in Pomona (see Structure and Design issue 24). From their original business of supplying and servicing irrigation equipment they have now grown to become one of the leading manufacturers of extruded PVC pipes for irrigation, plumbing, mining and all the related industries that need top quality products at affordable prices. They have recently expanded yet again to incorporate the manufacturing of their own exclusive brand of water storage tanks – Jumbo tanks.
Their exclusive range of Jumbo tanks are available in a variety of sizes for customer convenience; 1,000 litres, 2,000 litres and 5,000 litres. Unlike many other brands Jumbo tanks have a matt grey finish which helps to make the tanks inconspicuous and has the advantage of making the tanks blend easily in most garden or domestic applications. A unique built in feature of Jumbo tanks is their three layer structure. The interior of the tanks is pure white making it easy to spot any impurities in the water. The inner layer is made from virgin food grade plastic which is odourless and tasteless making it ideal for storage where water is used in food production. It also eliminates the need for stored water to be treated before being used helping to cut production time and costs. The inner lining is non-reactive so the tanks can be used to store not just water but also for storing chemicals like acids or for water soluble fertilisers used in fertigation.
(Wikipedia defines fertigation as “the injection of fertilisers, used for soil amendments, water amendments and other water-soluble products into an irrigation system.”) The second or middle layer is black which is UV resistant and helps to prevent algae growth and the outer layer is an attractive matt grey. Most plastic water storage tanks are manufactured using the rotor mould system whereby molten plastic is poured into a mould that rotates on two axes to spread the liquid plastic around evenly. It’s a fairly complex and lengthy process. DripTech uses a unique combination of extrusion and blow moulding which is much quicker and produces a better quality product. The process is so fast that in October DripTech was able to supply over 900 units to their customers. The machinery is capable of producing around one tank every ten minutes. Although the tanks are slightly more expensive to manufacture than conventional tanks the high volume of production means that they can be sold at very competitive prices.
High density polyethylene plastic pellets are processed with heat and high pressure and extruded in a circular curtain that’s shaped like a large hollow tube. The tube is forced into a two sided mould and pressurised air is forced in to form the molten plastic to the desired shape. All three layers are extruded at the same time. The void underneath where the pressurised air is forced in later becomes the opening for the lid of the tank, so the tank is in effect manufactured upside down. The three individual layers contribute to make the tank extremely rigid and very robust.
In fact DripTech are so confident about the quality and durability of their tanks that they offer a 10 year warrantee on their products. One advantage of the rigid nature of the tanks is that the opening for the lid can be formed with deep threads so that the lid can be tightly screwed on. This prevents insects, rodents and dust from getting in to the tank. Apart from storing water the food grade inner lining and the tightly sealed lid make the tanks ideal for grain storage, particularly for small scale rural farmers. Once the lid is sealed on the tank the grain is safely stored and becomes impervious to weevils and other pests. The 1,000 litre tank is the ideal size for grain storage and the three layer structure makes it very tough.
DripTech visited China to view various types of machinery capable of producing tanks using the combined extrusion and blow moulding method. They saw several options and were considering a smaller machine but eventually decided on a custom made machine which was tailored to perfectly suit their needs. The machine was imported directly from China and a specialised team of Chinese technicians came to Zimbabwe to assemble it and train the local staff on the running and maintenance of it. The equipment arrived in Zimbabwe in February this year and by May it was fully operational. It’s the first machine of its kind in Southern Africa. The machine is housed in a custom built warehouse designed and built by Agristructures.
The manufacturing plant is located at 11 Douglas Road in Workington so it’s close to DripTech’s sales outlet on Coventry Road. There’s a 10 tonne overhead crane on rails in the warehouse to move around the very heavy steel moulds used to produce the different size tanks and in addition the platform which creates the extruded plastic curtain can slide up and down to accommodate the different sizes. The concrete floor slab had to be specially reinforced to take the weight of the machinery. The production process uses quite a lot of electricity so there’s a dedicated substation on site and DripTech has invested in a sophisticated three phase voltage regulator and variable transformer to help ensure a steady supply. In the event of there being no electricity supply DripTech also has a huge 650Kw generator as a backup to ensure uninterrupted production.
To find out more visit one of their branches located on Harare Drive in Pomona, Second Street extension in Belgravia, Glenara Avenue in Eastlea or Coventry Road in Workington. They also have a regional branch on Tembwe Street in Mutare. You can call +263 (0)867 700 7000 for enquiries Or visit their website: www.driptech.co.zw
text: Michael Nott
photos: Structure & Design