Head Office: No. 87- Next to Mellat Bank After Shiraz Crossing, Molla Sadra Ave. Vanak Sq. TEHRAN-IRAN
Tel:(+9821)8803 7820-8803 7822 Fax: (+9821)8803 7816
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1- Melt flow Index M.F.I (ISO 1133): During this test, melting speed of materials in a certain temperature and time is measured so that their treatment inside an Extruder is examined based on results. This test is carried out on the materials (in order to confirm their quality) as well as products during which the quantity of MFI in the product should not differ more than 0.2 gr/lomin with that in Raw material.
2-Designation of Density (ISO 1183): The Density of materials as well as products is designated in the flood-making manner using a very exact balance for fluids with a certain density. Meanwhile, the density number of product indicates quality of production process.
3-Designation of carbon percentage (ASTM D 1603): The carbon Percentage is always designated in materials and the final product. To do so, certain amount of material is pyrolized under the effect of net N-Gas in a furnace at a temprature of 800˚c and the remaining carbon will be burned off under the effect of oxygen gas until the quantity of ash( added materials) in the first sample is designated. The permitted percentage of carbon in polyethylene pipe is 2 to 2.5% in weight which should be distributed evenly all through it. * There will be centralization of tension in areas where the agregation of carbon is beyond the permitted limit as a result of which the pipes will become vulnerable. In case the carbon amount is below the standard limit, stability of pipes against the sun's ultra-violet ray will be reduced.
4-Tensile Test (BS2782-EN63-ASTM D 2412): The mechanical Properties of polyethylene pipes including maximum stability against an outer bar, the extent to which the legth of pipe changes in the rent spot, designation of elasticity coefficient as well as the curvature rate under the effect of three-spot Bars can be measured by this machine, and the performance of product during the operation can be examined based on the results of the test.
5-Hydrostatic pressure test (EN 921): To examine the stability of the product against Hydrostatic pressures, the above mentioned test is carried out with the most modern and precise machinery in GazLouleh manufacturing company's laboratory-During the test, having been immersed in the water, the sample pipes will undermine a constant inside pressure at the tempreture of 20˚c for 100 hours or 80˚c for 165 or 80˚c for 1000 hours in respect of their sizes and materials. Any defect found in the samples (such as burst, bulging, local swelling, leaking and capillary flaws) means that the product should be rejected.
6-Burst pressure test(ASTM D 1599): During this test, the sample pipes are floated in a pool with a constant temperature of 23˚c, following which they will undermine the effects of increasing linear inside pressure in such a way that they will swell up within a period of 60 to 70 seconds and then burst. The pipe having been produced by using desirable as well as proper process will take the form of plastic, swell up and then burst in a beak-tip state. the bursting section will be vertical on the long axis of the pipe in such a state. The pipe which does not swell up but get cracked along the length, is rejected.
7-Heat Reversion test(ISO 2505): During this test, approx 30 cm long samples are placed in an oven with hot air circulation of (110+2 c) for about one to three hours (with respect to the wall thickness of the pipe wall) and then the decrease of the sample length as compared to the origin length is calculated. The length of polyethylene pipes, following the thermal cycle and after they've been cooled will change in such a way that the length of pipe will become shorter than its first state in a normal temprature. This could lead to the change in roundness of the installed pipes. Therefore, having completed the test, the standard limit of linear changes (approximately up to 3%) will be studied in the laboratory.
8- dimensions measurement and inspection of the pipe ISO 11922): Polyethylene pipes should be devoid any kind of unflatness (inside and superficial ) and deep pores. Slight dents can be overlooked , providing they would not decrease thickness of the pipes below the standard.
It should be mentioned that due to its flexibility, the polyethylene pipe will be deformed while being carried or installed. Of course after the connection has been completed , this state will be removed and the pipe will be restored to its origin form, once the fluid has been flowed in the pipe and the pressure exerted during the next stages.
This test will be carried out on materials in order to designate the rate of thermal resistance by the materials. The time needed for polyethylene which is to be destructed according to the above standard , should not be less than 20minutes.
10- Squeezing Test (ISO-4437 , EN-12106) : During this test , sample pipes with length of 8 time of pipe diameter will be provided and immersed in freezing water for 10 hours. Having been compressed by the squeezer for one hour, the pipe will be restored to its origin from by Re- Rounding machine. It will then undermine the pressure of 8 c for 1000 hours after having been closed on two sides by the cap. Even the slightest harm should not be inflicted to the pipe , based on the standard.
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