Saba Azar pipe Miyaneh Laboratory is equipped with the most complete laboratory equipment. This laboratory has been able to provide a wide range of services to customers by having an experienced and expert staff in the field of chemistry and polymer and by conducting detailed tests on polyethylene pipes based on domestic and foreign standards.

Saba Azar pipe Miyaneh Laboratory has been operating since 2006, Since 2013, it has been selected as a partner laboratory of the National Standard Organization and in 2017, it succeeded in obtaining the ISO/IEC 17025 standard.

The tests that are performed in this laboratory:

ESCR test based on ISIRI8988 and ISIRI7175-8 standards:

In this test, which is specific to LDPE polyethylene materials and pipes. The samples are bent under mechanical stress inside the tubes containing the agipal and they are placed in the test temperature of 70 degrees Celsius for 1 hour.

After the test time has passed, they are visually checked for cracks.

In another method, the samples are cut by a notching machine and subjected to stress for 1000 hours and after the passing of the test time, the cracks are examined.

Density based on INSO7090-1 standard

The physical properties of polyethylene can be predicted from the density of the material with a good approximation. For this purpose, in this company, the density test is performed by flotation method on raw materials and products.

INSO6980-1 standard melt flow index

This test is a method for measuring the mass flow rate of melt of soft heat materials, under certain temperature conditions and in grams per ten minutes.

Measuring the amount of soot based on the INSO1990 standard

Polyethylene is destroyed by exposure to the sun’s ultraviolet rays and in the presence of oxygen. Polymer chains are destroyed during a radical reaction and its structure changes.

As a result of destruction, the physical and mechanical properties of the piece will drop significantly. In the case of products that may be exposed to sunlight during storage or use (such as polyethylene joints), the use of anti-ultraviolet radiation materials through a proper mixing process to the raw materials is necessary.

Carbon black is usually one of the used options due to its very good properties in absorbing ultraviolet rays. The acceptable result is 2-2.5 percent.

Soot distribution based on ISO18553 standard

How the carbon black is dispersed in the polymer is very important to resist UV rays. If the soot particles are not crushed by the mixing process, they can act as a stress concentration center and cause failure.

Also, the distribution of carbon black particles throughout the polymer field is necessary to fully protect the product against UV rays, The acceptable result for this test is less than or equal to 3.

Thermal return based on ISO2505 standard

During this method, a specific length of pipe is heated at 110 or 100 degrees Celsius depending on the type of pipe.

After the heating stage, the pipe surfaces are checked for defects such as cracks, blisters or separation of the walls and the percentage change in the length of the pipe.

Dimensional control based on INSO2412 standard

One of the most important factors in the design of pipes is the dimensional specifications. The first dimensional characteristic is the thickness of the pipe wall. The lowness of the mentioned characteristic reduces the required strength, and its highness leads to the reduction of the inner diameter of the pipe and as a result, the reduction of the effective output flow rate.

Another important parameter in the design of pipes is the size of the outer diameter. The high value of this parameter can cause problems in the installation of pipes and fittings, On the other hand, its lowness, in addition to the recent problem, reduces the effective flow rate of the pipe output.

Also, the dimensional changes of the diameter of the pipes make the sealing of the connections not done well. The two-width parameter of the pipe also has an effect on the way of installing pipes and fittings and their sealing.

Also, the double width of the pipe has an effect on the fluid velocity profile and its velocity inside the pipe, which in gravity pipes, this change in velocity causes acute problems in fluid transfer.

Hydrostatic test based on ISIRI 12181 standard

The hydrostatic pressure and burst test is one of the important parameters for investigating the physical and mechanical properties of polyethylene pipes to determine the compressive strength of the pipes under pressure and to determine the lifespan of these pipes for long-term use periods at different temperatures.

This test is performed at two temperatures :

1) 1) Test at 20 degrees Celsius :

In this test, after being immersed in a water pool at a temperature of 20 degrees Celsius for 100 hours, the pipe samples are placed under a constant internal pressure, after which there should be no cracks, breaks, swelling or any cause a defect.

2) 2) Test at 80°C :

In this test, the sample is subjected to pressure for 165 hours at a temperature of 80 degrees Celsius. After this period, there should not be any cracks, bursts, bloating, local swelling, leakage, hairline cracks or any defects.

Tensile test based on ISO6259-1 standard

Various mechanical properties can be measured in the tensile test. For this purpose, a sample is prepared along the length of the pipe according to the standard and is subjected to uniaxial tensile force at a certain speed.

At this stage, the sample should undergo plastic deformation and at least 350% of the initial length should be increased. Finally, it will lead to failure and tearing of the sample.

Elongation percentage, yield point, breaking point and Young’s modulus are among the important parameters and mechanical characteristics of polymer that can be achieved in this test.

Among the things that are very important in the tensile test and indicate the quality of pipes, machines, raw materials and the production process include the following:

• surrender point.

• Increase in length (at least 350% of the initial length).

• breaking point.

The broken and torn part of the sample is one of the things that can tell the quality of the pipe and raw materials used to a large extent.

Thermal stability test (OIT) based on ISIRI7186-6 standard

Another parameter that determines the efficiency of polymer materials and parts is induction oxidation time. Thermal stability test is a qualitative measurement of the degree of stability of the tested material.

Physical and chemical changes of materials are associated with thermal effects. These endothermic or exothermic changes represent the enthalpy released in the reaction, and the differential scanning calorimeter device measures the difference in heat flux between the sample and the reference material with respect to temperature or time under similar heating conditions.

This difference in flux is followed in the form of enthalpy of reaction and by enthalpy graph with respect to temperature or time.

The measuring equipment of this laboratory includes the following items:

• Pyrolysis device to determine the weight percentage of soot in the mixture or pipe
• Plastometer device (MFI) to determine polymer melt flow index
• Oven device to determine thermal return
• Scale with an accuracy of 0.0001 g to determine density
• DSC apparatus to determine thermal stability
• Microscope to check the distribution of soot
• Caliper and peripheral tape to measure pipe dimensions
• Tensile device to test the tensile strength of the pipe
• Electric furnace for soot percentage test
• CNC machine
• Tensile testing machine
• ESCR device
• Hydrostatic testing machine
• Kate Dansity
• Reference equipment