Quality Control

The circumferential and axial load-bearing capacities of the produced pipes are verified through routine tests. Additionally, the structure and composition of the pipe are tested and approved.

Controls During Production:

• Raw material control tests

• Visual inspection

• Barcol hardness

• Wall thickness measurement

• Pipe length measurement

• Outer diameter measurement

• Hydrostatic leak test

Controls Performed on Samples:

Pipe Stiffness:

Specific stiffness is a physical property of the pipe and is a measure of its resistance to ring deformation under external load. Initial ring stiffness is the value obtained in N/m² when the pipe is tested with approximately 3% deflection according to ISO 7685 and EN 1228, calculated using the following formula:

S0 = F f / L y f = (1860 + (2500 * y/dm)) / 100000

Where: S0 = Stiffness; N/m²
F = Applied Force; N
f = Deflection Factor
L = Sample Length; m
y = Vertical Deflection; m
dm = Average Diameter; m

Deflection Test Without Damage or Structural Harm:

When tested according to ISO 10466 with the nominal deflections applied to the pipe sample, the sample must meet the conditions specified in the table below.

Ring Tensile Strength:

When samples cut circumferentially from the pipe are tested according to ISO 8521 and EN 1394, they must comply with the minimum value tables listed in international standards.

Axial Tensile Strength:

When samples cut axially from the pipe are tested according to ISO 8513 and EN 1393, they must comply with the minimum value tables listed in international standards.

SUPERLIT GRP pipe production technology includes a detailed quality control program. The production and testing of pipes and fittings in compliance with international and Turkish standards are ensured through this program.

Quality Control Tests:

Before production, raw materials are tested. The tests aim to verify the compliance of raw materials and produced products (pipes, couplings, fittings) with standards.

At SUPERLIT, certification activities in line with ISO 9001 standards are implemented through a total quality management approach involving the participation of all employees.

Performance Tests:

Coupling Performance Test:

Couplings are tested under the conditions specified in EN1119, ISO8639, and ASTM D4161 standards to verify their performance.

Long-Term Tests:

• Long-term damage pressure

• Long-term chemical resistance test (Stress-Corrosion Test)

• Long-term ring stiffness (in wet conditions)

• Long-term ring deflection test

Long-term tests are conducted for at least 10,000 hours to establish design values and allow for extrapolation. In other words, using the methods of ISO 10928, the necessary physical parameters for the specified nominal 50-year design life are determined. Typically, at least eighteen samples are prepared, and a series of data points are collected throughout the test period. A logarithmic regression graph is created from the test data using the least squares method. The performance values corresponding to the 50-year service life of the GRP pipe must comply with the tables provided in international standards.