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QUALITY CONTROL

Molniya LLC has testing lab accredited by Metrological service of Ukraine with the Accreditation Certificate №20-17 dd 23.10.2015. The laboratory is equipped with imported (Germany, Japan) high-precision equipment for physical-mechanical testing of raw materials, semi-finished and finished products.

The testing lab is entitled to sign the contracts with other accredited laboratories or companies for similar kind of works. 

As a responsible manufacturer, we pay great attention to the quality of zipper which is manufactured in accordance with the requirements of DSTU 4146-2003 and pre-production sample. The monofilament yarn is made in accordance with technical specifications №24.7-05407746-001:2009.         

The zipper goes through operating control, periodical examination and acceptance inspection.

Inspector conducts operating control every hour at each production section in order to check the size and appearance of semi-finished and finished products. Thickness gauge, magnifier, micrometer, calipers, templates for internal dimensions are used for accurate measuring. In case of discrepancy in technical process the cause and defect is eliminated immediately. 

The acceptance inspection is conducted at each section as well; we take 10% of every batch and examine its conformance to standard DSTU 4146-2003.

The production batch meets standard requirements if the number of defective units in selection is less or equal to acceptance sampling. In case defective goods are uncovered, the whole batch goes through the sorting out and additional acceptance control. 

Quality Certificate is generated for each production batch.          

The periodical examination is conducted quarterly and proved with protocol. We take 25 samples of every zipper types for this purpose. The periodical examination includes testing of the following physical and mechanical performances:

  1. Breaking force of closed-teeth zipper chain. The zipper corresponds to the standard requirements, if there is no separation of closed zipper teeth, separation of spiral from the woven tape or break down of tape under pressure.
  2. Connection strength of close-end or open-end bottom stop. The zipper corresponds to the standard requirements if there is no straightening of bottom stop fixing pins or separation of the stop from the woven tape under pressure.
  3. Shearing pressure of close-end or open-end bottom stop. The zipper corresponds to the standard requirements if there is no shift of the stop, woven tape breakage or straightening of fixing pins under the pressure.
  4. Fixation strength of slider with top stop. The zipper corresponds to the standard requirements if there is no shift of the top stop under the pressure or if the slider does not pass through it.
  5. Removal effort of the slider. The zipper corresponds to the standard requirements if removal effort of slider doesn’t exceed parameters indicated in the Tab.1.
  6. Fixation strength of the slider. The zipper corresponds to the standard requirements if there is no movement of the slider on the zipper chain under the pressure regulated by p. 6.3.13.
  7. Integrity of the slider. The zipper corresponds to the standard requirements if there is no separation of cap or puller from the slider under the pressure.
  8. Target operation time is 500-700 cycles. The zipper corresponds to the standard requirements if there is no woven tape breakage after test run. Decrease of breaking force index for closed zipper teeth up to 7% is acceptable (p. 6.3.12).
  9. Thermal stability. The zipper should keep an ability to open and close manually after testing.
  10. Chemical resistance. Tests are conducted with perchlorethylene. The zipper should keep the color and ability to open and close smoothly after testing.
  11. Color resistance after painting.

 

Control method for monofilament yarn:

  1. Monofilament yarn’s diameter control. It is executed with usage of micrometer and thickness gauge for each product unit with 10 measurements. The deviation of average factual diameter from nominal one must meet the standard requirements.
  2. Testing for breaking tenacity and extension coefficient of monofilament yarn at the moment of breakage. Five samples from every batch are collected for testing. Results must comply with the standards.
  3. Testing for linear shrinkage of monofilament yarn during the heating process in air environment. Five samples from every batch are collected for testing. Results must comply with the standards.
  4. Testing for linear shrinkage of monofilament during boiling. Five samples from every batch are collected for testing. Results must comply with the standards.
  5. Testing for non-circularity of monofilament. It is carried out with the help of micrometer taking three samples from every batch. Acceptable non-circularity must comply with standards.
  6. Definition of moisture level in dried up chips. Mass fraction of moisture in dried up chips is 0.005%.

Technical Specifications of Ukraine 24.7-05407746-001:2009. Table 2.

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