Hollow blow-molded seats are frequently used products. Therefore, after purchasing them, we need to inspect their appearance, mechanical properties, durability, and environmental friendliness to ensure compliance with standards. During inspection, we can check the following aspects:
Appearance Inspection: The seat and back of the hollow blow-molded seat should be integrally molded, without obvious bubbles, dents, cracks, missing materials, or other defects. The wall thickness should be uniform, with a deviation controlled within ±10% to avoid affecting load-bearing capacity due to localized thinness. The surface should be smooth and flat, without sharp protrusions, burrs, obvious scratches, or color differences. If the seat is colored, the color of products in the same batch must be consistent, with a color difference ≤3 levels. Edges and corners must be rounded with a radius ≥5mm to prevent bumps and injuries. Seat markings (such as seat numbers and logos) should be clearly printed, without blurring or peeling, and silkscreen or embossed printing should be firmly attached.
Mechanical Properties: The hollow blow-molded seat has a static load-bearing capacity of ≥250kg, showing no cracking or permanent deformation after loading tests. The seat surface withstands a 100kg dynamic impact, undergoing 500 repeated tests without damage or structural loosening. For folding models, the folding joint must withstand a lateral tensile force of ≥150kg without breakage or deformation. A 1kg impact hammer is used to impact weak points of the seat (such as the backrest edge and seat corners) from a height of 500mm; no cracks or damage are allowed after impact, only minor dents that do not affect use are permitted.
Durability: Xenon lamp aging tests are conducted according to GB/T 16422.2. After 1000 hours of testing, the seat shows no cracking or embrittlement, surface color difference ≤3, and tensile strength retention ≥80%, ensuring long-term outdoor use without fading or deterioration. After being placed in extreme temperature environments ranging from -40℃ to 80℃ for 48 hours, the seats showed no cracking or deformation and remained fully functional (the folding design opened and closed smoothly), adapting to different climates. The main seat material must be resistant to acid and alkali corrosion; after immersing samples in a 5% hydrochloric acid or sodium hydroxide solution for 24 hours, no significant corrosion or discoloration was observed on the surface. The accompanying metal frame (such as hot-dip galvanized steel) must pass a salt spray test; after a 72-hour neutral salt spray test, no significant rust was observed.
Installation compatibility: Key dimensions such as the width, seat depth, and backrest height of the hollow blow-molded seats must deviate from the design values by ≤±3mm to ensure neat arrangement and no misalignment after batch installation. After fixing according to the standard installation procedure, a horizontal thrust of 50N was applied, and the seat did not wobble; the connection between the frame and the seat was secure, and expansion bolts and other fasteners must meet building load-bearing standards to avoid the risk of detachment over long-term use. The modular design of the seats ensures a tight fit at the joints with gaps of ≤2mm, adapting to the assembly requirements of different grandstand layouts and facilitating individual disassembly and replacement.