Unpainted exterior mirror housings and base frames moulded from Mocom (ALBIS) ALCOM® ASA ASA 540/7 UV SV1156-12MCF are produced on hydraulic injection moulding machines with clamp forces between 8,000 kN and 12,000 kN. The compound is pre-dried in desiccant dryers at 80°C for 3-4 h, with a dew point no higher than -30°C, because ASA absorbs 0.2-0.3% moisture under storage at 60% relative humidity. Barrel temperature zones are maintained from rear to nozzle at 220°C, 235°C, 245°C, 250°C and 250°C. Melt temperature measured at the nozzle is held between 245°C and 255°C; residence time above 260°C is limited to less than 10 minutes to suppress thermo-oxidative chain scission in the acrylate rubber phase. Mould temperature is set at 60-80°C to reproduce grain topography on technical black and dark grey surfaces. Injection screw speed is adjusted to 60-120 mm/s and packing pressure is maintained at 60-80 MPa hydraulic. Regrind of unfilled ASA sprues and runners is blended at a maximum of 25 wt% with virgin material; higher regrind fractions reduce notched Charpy impact in ISO 179/1eA:2010 V-notch specimens. Weathering acceptance is referenced to SAE J2527:2017 accelerated exposure; after 1,000 h, the as-moulded surface should retain ISO 105-A02 grey scale level 4 or better. Terminal parts include body-colour mirror caps, mirror base brackets and turn-indicator bezels.

Can Unpainted ASA Meet PV 3929 Weathering for Black Cowl-Vent Grilles?

Cowl-vent grilles are injection moulded with a nominal wall thickness of 2.5-3.0 mm. The tool uses two valve-gated drops with gate diameters of 1.2-1.5 mm. Sequential valve-gate opening delays of 0.8-1.2 s are used to displace weld lines away from high-stress snap-fit retention ribs. The UV stabilization has to satisfy PV 3929 and PV 3930 weathering procedures; typical OEM acceptance limits for black exterior components are ΔE*ab ≤ 2.0 and residual gloss of at least 65% after 2,000 h. To minimise thermal degradation during colour dispersion, a pigment masterbatch with an ASA carrier is added at 2 wt%. The compound is segregated as reject if the melt temperature exceeds 280°C or residence time exceeds 12 min, because crosslinking in the acrylate rubber increases viscosity and generates splay. Moisture content at the machine throat is checked by Karl Fischer titration and maintained at or below 0.02 wt%. Finished components are the plenum cowl grille and its integral rubber seal retention channel, which must survive screw boss pull-out testing at 300 N without boss collapse.

Telecommunication cabinet latch brackets and hinge bosses

Outdoor telecommunication cabinet access panels, latch brackets and hinge bosses are moulded from the ASA grade where dimensional stability under cyclic heat is required. The latch bracket nominal wall is 3.5 mm; rib-to-nominal-wall ratio is kept at 0.6:1 to avoid sink marks on the textured exterior. Thread-forming screw bosses use an outer diameter of 2.0-2.5 times screw outside diameter and a minimum engagement depth of 2.5 times screw pitch. Core-ejector contact area is maintained at not less than 8% of projected part area to prevent ejection cracking. Melt temperature is set at 240-260°C and mould temperature at 60°C; screw back-pressure is 5-10 MPa and screw surface speed is limited to 0.1-0.25 m/s. The material is evaluated for UL 94 HB and, for interior remote parts, glow-wire ignition at 550°C according to IEC 60695-2-11:2021. Outdoor weathering is assessed by ISO 4892-2:2013 for 1,000 h; the exposed surface must show no cracking after ISO 178:2019 flexural modulus determination. Published data for this exact grade is limited for long-term cabinet sealing loads, so creep testing under 23°C and 60°C must be performed before series approval. Terminal parts include latch brackets, hinge bosses and cam-lock housings.

When garden debris blowers require fuel and lubricant contact

Handheld garden blower shroud halves and grass trimmer covers are moulded from the ASA grade when weatherability is required without a paint layer and when occasional fuel and lubricant contact occurs. The halves are joined by ultrasonic welding; energy director width is 0.4-0.6 mm, height is 0.4 mm, and the shear joint is 1.5 mm deep. Chemical resistance is assessed by ISO 175:2010 immersion in reference fuel C and mineral oil at 23°C for 24 h; acceptance is no significant change in tensile elongation at break according to ISO 527-2:2012. Fuel and oil contact is discontinuous, not permanent immersion, because acrylate rubber swells in aromatic hydrocarbons. Nozzle melt temperature is set at 240°C, below the decomposition range of lubricant-resistant additive systems. A screw with 20:1 L/D ratio and reverse-taper tip is used to avoid hold-up zones. Regrind is limited to 15 wt% in these components because repeated welding requires consistent melt viscosity. Texture depth is specified as VDI 24 to VDI 27, and gloss is kept low to mask flow lines. Terminal parts include blower fan shrouds, grass trimmer covers and recoil starter housings.

Roof-mounted telemetry units, solar radiation sensors and GPS antenna shells moulded from the same ASA grade require simultaneous resistance to high-UV altitude exposure and low-temperature impact. The parts are injection moulded on machines with clamp force between 1,200 kN and 3,000 kN; shot weight is kept above 35% of barrel capacity to avoid long residence times. A two-cavity tool is generally avoided because asymmetric part geometry produces core-shift and wall-thickness variation in the sealing groove. The seal groove compression ratio is set at 0.8 for a silicone gasket of Shore A 45-55. Cavity-side mould temperature is 80°C and core-side mould temperature is 60°C to reduce differential shrinkage in 2.0 mm wall sections. Notched Charpy impact is tested according to ISO 179/1eA:2010 at -20°C; a lower acceptance limit of 8 kJ/m² is typically specified in outdoor electronics material standards. UV stability after 1,500 h of ASTM G155:2021 cycle 1 is evaluated on RAL 9011 black surfaces; the accepted limit is ΔE*ab ≤ 1.5 with no impact cracking. Published data for the overmoulded interface with polyamide attachment rings is limited, so peel adhesion at 23°C and 80°C must be validated before series release. Terminal products are sensor enclosures with integral gasket grooves and UV-resistant mounting bases.

Outdoor electrical enclosures carry UV and impact retention obligations

Low-voltage distribution boxes, surge-protection enclosures and outdoor socket housings are injection moulded from the ASA grade when visual retention and mechanical integrity are specified for unpainted external surfaces. Wall thickness is set between 2.0 mm and 3.5 mm, with a maximum flow length-to-thickness ratio of 150:1 from the gate. The resin is dried to 0.02 wt% moisture content and processed at a melt temperature of 245°C with mould temperature of 70°C to minimise moulded-in stress. Holding pressure is profiled from 70 MPa to 35 MPa over 6 s, and cooling time is 20-30 s for wall thickness 3.0 mm. The enclosure covers are tested for impact at -20°C using ISO 6603-2:2020 puncture test; no visible cracks are permitted. Flammability classification is UL 94 HB, and glow-wire testing to IEC 60695-2-11:2021 at 650°C is used for live-part separation. Weatherability is verified under ISO 4892-2:2013 for 500 h; the colour change limit is ΔE*ab ≤ 2.0 and no surface chalk is observed. Terminal products include slate grey and black covers and base shells for IP55 and IP66 low-voltage outdoor installations.