Qingdao Conet International Trade Co.,LTD.

• Incoming material inspection Every batch of rubber compounds  is inspected against material certificates upon arrival. Physical properties such as hardness, tensile strength and elongation are tested before use; unqualified raw materials are rejected.

• Fixed formula management: Ingredients (vulcanizing agents, plasticizers, fillers) are measured by fixed ratio to avoid batch color difference and hardness fluctuation. Different materials are produced on separate lines to prevent cross-contamination.

• Mixing process: Mixing temperature and duration are strictly controlled to ensure uniform compound and prevent local hardness inconsistency and hidden air bubbles. Every roll of compound is sampled and checked.

• Calendering / forming: On-line thickness monitoring keeps thickness tolerance within range and controls surface flatness, minimizing scratches, particles and pinholes.

• Vulcanization process: Vulcanization temperature, pressure and time are tightly controlled and fully recorded for traceability. Under-cure leads to tacky surface and poor performance; over-cure causes brittleness and cracking.

• Roving inspection: Inspectors regularly check surface defects, dimensions and color. Bubbles, impurities and broken edges are isolated and reworked immediately; defective goods never enter the next process.

Every batch of finished rubber sheet is sampled and tested for physical performance as required:

• Hardness (Shore A)

• Tensile strength & elongation at break

• Aging, ozone and oil resistance

• Appearance: no bubbles, pinholes, impurities, cracks or unevenness

• Dimension re-check: thickness, width and length tolerance

QC reports can be provided; third-party inspection is also welcome.

Our packaging system is engineered to keep rubber sheets intact throughout storage and global transit. Every roll is individually wrapped with protective plastic film to guard against surface scratches, dust, moisture and contamination.

Finished rolls are stacked neatly on robust, fumigation-free plywood pallets  or EU pallets compliant with export requirements. Heavy-duty strapping secures the whole load to stop movement during shipping. Corner protectors and buffer pads are fitted at vulnerable edges to eliminate pressure marks, deformation and friction damage. Waterproof, durable labels are affixed to mark specifications, batch numbers, dimensions and quantities for straightforward stock checking.

For ocean freight, the full pallet can be overwrapped with stretch or shrink film as an extra moisture barrier. This standardized packaging safeguards your rubber sheets, ensuring they arrive clean, undamaged and ready for immediate use.