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BackChevron Polyethylene Pipes: Quality Control
Chevron’s Atyrau Polyethylene Pipe Plant is a pioneer of the polyethylene pipe production in Kazakhstan. Since 2003, the company has produced thousands of tons of pipes for various facilities in oil industry and public utility service, thus contributing to the wide spread of polyethylene pipes in the country. As a result, a whole industry of polyethylene pipes production has emerged, and over 70 producing companies have been created in Kazakhstan since 2008. Today, the annual output of polyethylene pipes in the Republic has reached 80 thousand tons.
To succeed in this new competitive environment, Chevron has chosen the strategy of high quality manufacturing which ensures extended service of pipes for up to 50 years, guarantees cost effectiveness and minimizes the risk of emergencies. Unlike many other Kazakhstani producers, Chevron uses stabilized black polyethylene HDPE 100+ for the production of its pipes. The company selected its partners among well-known suppliers of raw materials such as LyondellBasell, Borealis and Tasnee.
Chevron pipes possess another important advantage – accurate observation of dimensions (out-of-roundness) of pipes prescribed by Republic of Kazakhstan standards. The plant produces pipes exactly as per the given parameters, and the Quality Assurance Department strictly controls compliance with these criteria. For a client, it means that the pipes will contribute to the project reliability at all points and easily fit to all the fittings.
The high capacity of Chevron plant’s lines is also worth mentioning. During the construction season, the pipe production time could be of critical importance. Chevron plant with its five production lines is capable of swift completion of multiple orders.
Sometimes producers tend to reduce the cost of their products by using low-quality raw materials instead of increasing the efficiency of production and implementing new technologies. The quality of the raw material (in our case its black PE grains) plays an important role in the quality of the produced pipes. According to standard requirements, it is prohibited to use uncolored polyethylene and then color it in the process of producing the pipes. Polyethylene must be colored with soot during the original production of the raw material.
The prohibition of the use of uncolored polyethylene has been introduced on purpose. The existing equipment for pipe production does not allow to achieve the required combination of soot when mixing in the hot melt. This results in deterioration of physical and mechanical qualities of pipes, as well as of their UV resistance, consequently leading to reduction of shelf life and further usage.
Chevron has developed a set of recommendations which help consumers select high-quality pipes and avoid products from unscrupulous producers.
First, pay attention to the guarantee period of pipes. It must at least be 10 years, though according to current standards, a PE pipe must serve for up to 50 years!
Besides, make sure that your producer has a plant laboratory which carries out a minimum acceptance tests for each batch of pipes (visual appearance, dimensions, yield stress and elongation), as well as regular hydraulic pressure tests. Potential purchasers of pipes are recommended to visit the laboratory and the warehouse with raw materials. While on a plant visit, pay attention to the mandatory availability of raw materials dehydration facility and take part in the pipe tests (preferably, yield stress and elongation tests) and compare the results with standard requirements.
Such tests, in addition to the check of dimensions, must be conducted for each batch of pipes and is referred to as an acceptance test whose failure makes a pipe unfit for use. In addition, the extension of pipes will show clearly whether the low quality uncolored polyethylene was used in the pipe production. Pipes must be labeled and be of bright and saturated black color.
A counterfeit colored pipe could easily be distinguished when the chippings from the pipe end are displayed to the light – its color is not brilliant-black but grayish. You can easily get the chippings when cross cutting the pipe before the welding. Conduct this inspection twice: first time - when choosing a supplier, and second time - after receiving the product. To assure the quality of supplied products, include a provision in the supply contracts to conduct tests in a third-party laboratory at various stages of products supply: early, middle and final stages.
Availability of the valid conformity certificate and certificate (passport) for raw material (black polyethylene in grains) are of great importance. They must confirm the conformity of the product to the requirements of the state standards, specifications and etc, and include information on grade and manufacturer of the raw material.
If these recommendations are followed, your company can be sure that it is purchasing a reliable product. Please note that when choosing polyethylene pipes and any other large manufactured goods, one needs to consider the full cost of ownership which includes the cost of associated goods and services, operation and repair costs. At the same time, the lowest cost at the counter does not guarantee low full cost of ownership as further repairs will quickly absorb the savings from the purchase of cheap pipes.