T/AQB 55-2024 Land-buried soil-resistant, impermeable, organic-reinforced, toughened tube material

Scope

Main technical contents: 1. Ring stiffness Ring stiffness is a physical parameter that measures the ability of pipes or pipe fittings with a ring-shaped cross-section to resist deflection (radial deformation) under external loads. It is a key indicator for buried plastic pipes, representing their resistance to external pressure loads. These loads include soil weight, static loads from the ground, and dynamic loads from passing vehicles. Based on actual engineering usage, this standard sets four ring stiffness grades: SN8, SN10, SN12.5, and SN16, which align with relevant national standards. 2. Impact performance Impact performance is a test and evaluation method for the low-temperature impact resistance of pipes. Through drop hammer impact tests, the pipes’ ability to withstand instantaneous impacts can be verified, allowing for the measurement of their toughness or resistance to damage under high-speed impact conditions. Compared with related national standards, the test method increases the drop hammer’s mass and raises the quality requirements for pipes. 3. Ring flexibility Ring flexibility refers to the ability of pipes to withstand radial deformation while maintaining their structural integrity. According to the specified test speed, the pipe specimen is compressed until its outer diameter deforms by 40% of the original value. The test then observes whether the specimen cracks or shows delamination between the two walls. One hour after the test, the inner diameter of the compressed section is measured to calculate the retention rate. This standard requires that the pipe exhibit no cracks or delamination between the two walls, and that the inner diameter retention rate exceed 90% one hour after the test. Compared with related national standards, the compression deformation has been increased from 30% to 40%, and the retention rate requirement has been strengthened, further enhancing quality standards. 4. Oven test The oven test evaluates the b

Development Information

Related Standards