EMS-Grivory Grilamid LV-30H FWA nat is an injection-moulding compound based on polyamide 12 containing 30 wt% short glass fibre, supplied as natural-colour pellets and evaluated in the dry as-moulded condition. The FWA designation identifies a food-contact and potable-water formulation platform; however, certification for any fabricated component is article-specific and must be confirmed through the applicable migration or leaching protocol. Published technical data for this exact grade are concentrated in the manufacturer’s material documentation; values cited below are typical, not specification limits. Under ISO 1183-1, density is approximately 1.24 g/cm³. Compared with glass-filled PA6 and PA66 of similar loading, the PA12 matrix reduces equilibrium water uptake under ISO 62 and narrows moisture-induced dimensional change.

Does 30% glass loading alter the melt-processing window of PA12?

The melt-processing window for this compound is narrower than for unreinforced PA12 because glass fibre increases melt viscosity and heat transfer to the polymer. Barrel temperature settings between 250°C and 280°C are typical, with melt temperature near 270–285°C. Mould-surface temperatures of 60–100°C improve flow length and reduce premature shell solidification in thin walls. The compound should be plasticated on reciprocating-screw injection-moulding machines with screw L/D ratios of 20:1–25:1 and hardened screw flights, non-return valve, and barrel lining. Low-to-moderate backpressure of 0.3–0.7 MPa hydraulic is employed to limit glass-fibre length attrition. Residence time above 290°C should be limited to less than 5 min to prevent oxidative degradation of the PA12 backbone. Published melt viscosity curves for this exact grade are not fully disclosed in public sources; setting a slightly positive screw-recovery profile and avoiding high screw speed above 0.2 m/s circumferential velocity is standard practice for highly glass-filled polyamides.

Predrying is mandatory at relative humidity 60% or higher. A desiccant dryer set at 80°C for 4–8 h reduces pellet moisture below 0.10 wt%; moisture analysis by ISO 15512 or Karl Fischer titration is recommended. Insufficient drying produces surface splay, bubbles, weld-line weakness, and hydrolysis-induced molecular weight reduction. Because PA12 reaches a lower equilibrium moisture than PA6 and PA66, moisture recovery from ambient air is slower in dry-as-moulded parts; closed hopper systems with dry-air purge are preferred in high-humidity production halls. Fibre attrition occurs primarily during melting in the compression zone and at the non-return valve. Published polyamide compounding studies indicate that fibre length after injection moulding of short-glass reinforced grades can fall below 300 µm when high shear is used. Since the tensile modulus of this grade is fibre-length-sensitive, use of a general-purpose screw with compression ratio above 2.5:1 and backpressure above 1.0 MPa intensifies length reduction and should be avoided.

Glass fibres orient preferentially in the melt-flow direction during filling. In thin-wall parts, the oriented shell-core morphology produces anisotropic shrinkage under ISO 294-4; flow-direction shrinkage may be near 0.2–0.4%, while transverse shrinkage can approach 0.6–1.0% depending on gate geometry and wall thickness. Published anisotropic shrinkage data for this exact grade are limited. Gate placement should therefore align the major dimensional tolerance axis with the dominant flow direction, or a radial gate arrangement should be used for round parts such as filter housings.

Mechanical response of dry mouldings: expected value band

Dry as-moulded tensile modulus under ISO 527-1/-2 typically ranges from 6,000 MPa to 7,500 MPa. Tensile stress at break is approximately 100–120 MPa, with nominal strain at break of 3–5%. Flexural modulus under ISO 178 falls in the same stiffness band, while notched Charpy impact strength under ISO 179/1eA at 23°C is approximately 10–14 kJ/m². Low-temperature notched Charpy values may remain at 8–12 kJ/m² at -30°C; published data for this exact grade are limited. Heat distortion under ISO 75-1/-2 at 1.8 MPa is approximately 160°C, and Vicat softening under ISO 306/B50 is approximately 170°C. The melting point determined by ISO 11357-3 is near 178°C.

Conditioning under ISO 1110 at 70°C/62% RH plasticises the PA12 matrix. Because polyamide 12 has a lower amide concentration than PA6 or PA66, moisture-induced modulus suppression is smaller. For short-glass PA12, tensile modulus after conditioning may be 10–20% below the dry value; a comparable PA6-GF30 can lose 30–40%. This difference becomes relevant for snap-fits, internal gears, and press-fitted metal inserts in humid environments. Design calculations for water-contact parts should use conditioned properties, not dry data. The dry designation in this product description specifically means data generated on specimens in the dry as-moulded state before moisture absorption has occurred.

When drinking-water approval narrows additive and pigment choices

FWA-formulated grades are intended for food-processing equipment and potable-water components. The base resin is generally declared for EU 10/2011 and FDA 21 CFR 177.1500, but final-article compliance requires migration testing under EN 1186 or the relevant FDA extraction protocols. The natural-colour version avoids carbon black and heavy-metal pigments that complicate water-contact approvals. Organic masterbatches used downstream must themselves carry appropriate food-contact documentation. Potable-water certifications such as KTW-BWGL, DVGW W270, WRAS, or ACS may be issued for specific articles and colours; they are not transferable to other geometries or processing lines. Hot-water exposure above 60°C requires additional oxidative stabilisation validation because water extracts antioxidants over time and can shift the organoleptic profile.

Chemical resistance of this compound follows the PA12 profile. The polymer withstands aliphatic hydrocarbons, mineral oils, greases, diesel fuel, weak alkalis, and many neutral aqueous media. Strong mineral acids, phenols, concentrated formic acid, and strongly oxidising media attack the matrix. Some zinc chloride solutions can stress-crack PA12 at elevated temperature. In potable-water service, chlorine dioxide and ozone residuals may reduce lifetime; published data for this exact grade under disinfectant exposure are limited and must be verified by application-specific testing. The lower amide density of PA12 also decreases the rate of water migration through the wall of a moulded part, but it does not eliminate water diffusion or extraction of low-molecular-weight constituents.

Comparative property envelope with glass-filled PA6 and PA66

PA6 and PA66 at 30 wt% glass fibre typically show higher dry tensile modulus, commonly 8,500–10,000 MPa, but their saturation water uptake is commonly 6–8 wt% under ISO 62, compared with approximately 1.2 wt% for PA12-GF30. This produces larger dimensional changes and a greater conditioned modulus depression in PA6 and PA66. The density of PA6-GF30 and PA66-GF30 is around 1.36–1.38 g/cm³, whereas this PA12 grade is approximately 1.24 g/cm³. Low-temperature impact resistance of PA12 can be superior because the longer aliphatic chain retains segmental mobility below 0°C. Against PPS-GF30, the Grilamid LV-30H FWA nat grade has lower service temperature and higher moisture sensitivity, but offers easier processing, lower density, and better weld-line ductility. Selection between these materials depends on peak operating temperature, chemical exposure, dimensional tolerance under humidity cycling, and food/water certification requirements.

Feed, drying, and melt-conditioning boundaries for dimensionally stable parts

Feeding natural 30% glass-reinforced pellets is stable in single-screw and multi-cavity machines. Hopper throat temperature should remain below 80°C to prevent pellet bridging caused by surface softening in the feed zone. A desiccant-hopper arrangement with dry-air dew point of -30°C or lower is preferred. Holding pressure and time must compensate for glass-fibre-filled melt, which shows reduced compressibility and higher frozen-layer growth. Packing pressures between 50 MPa and 80 MPa hydraulic are typical for technical parts, but gate dimensions and flow length determine exact settings. Published processing recommendations for this exact grade are limited; mould trials on 80–120 t machines with 25–35 mm screw diameters are often used for small-to-medium water-handling components.

In a cold-water meter body moulded from Grilamid LV-30H FWA nat, the combined requirements are internal pressure resistance, thread integrity, and stagnation-water compliance. The part is typically gated near the centre of the cylindrical bore to produce circumferential glass orientation and reduce leakage-path weld lines. Hot-runner valve gates with sequential opening are used on multi-cavity tools to balance fill and maintain cavity-to-cavity weight variation below 1.0%. Mould inserts for threads require through-hardened cores and positive ejection because glass-filled PA12 exhibits earlier solidification and higher stiffness than unreinforced PA12. Hydrostatic burst testing under ISO 9080 or ASTM D1598 is performed on finished assemblies; the material datasheet alone does not assign a pressure rating.