Applications and Grade Selection
What each grade is normally used for, and what to check before you specify it.
Pressure pipe, drainage, conduit and fittings. Requires a consistent particle size and a low volatile figure so the line runs without weld-line or porosity defects.
Profiles & Construction
Window and door profiles, cable trunking and building profiles. Fusion quality and surface finish drive the choice here, because these products are sold on appearance.
Insulation and sheathing compounds. Electrical performance and the residual vinyl chloride figure are the decisive checks for this segment.
Agricultural and industrial film, calendered sheet and artificial leather backing. Clear work places a premium on fish eyes and impurities.
Bottles, blister packs, rigid sheet and injection-moulded parts. Low volatiles and tight impurity control keep the product optically clear.
The general rule
Higher viscosity means higher molecular weight, which gives a stronger melt and better mechanical properties, but a slower fusion step and a narrower processing window.
For rigid products — pipes, profiles, fittings, window frames — the choice is driven by surface finish and impact strength, which points at the middle of the range (SG5 and SG6). For soft products — film, hose, footwear, artificial leather — the choice is driven by flexibility and melt strength, which points higher (SG2 to SG4). For clear work the deciding factor is not the viscosity but the impurity count and the fish eye figure, which is exactly what separates premium from first grade.
Calcium carbonate filler loading shifts the same trade-off: more filler means a stiffer, cheaper compound that fuses faster, and it also changes the finished product density. Tell us the filler loading in your formulation and we can tell you which grade and grade level to order.
Grade-to-application guidance was last checked against the published specification table .