Extrusion blow moulding of UN-certified industrial packaging in the 20 L to 250 L class uses the high-viscosity melt of Idemitsu HDPE CALP H100 to maintain parison stability during accumulator-head transfer. Physical-property certificates should report density under ISO 1183-1 and melt-mass flow rate under ISO 1133-1 at 190 °C/2.16 kg; production trials in container plants are normally run with density variation within ±0.002 g/cm³. On production-scale machines with 80 mm–120 mm extruder diameter and 25:1–30:1 L/D, the material is processed at 190–225 °C, head pressure 25–35 MPa, parison die gap 0.8–2.5 mm, preblow 0.05–0.15 MPa, final blow 0.6–0.9 MPa, and mould water 8–15 °C. A closed-loop formulation for this sector typically includes 70–80 wt% virgin HDPE CALP H100, 20–30 wt% post-industrial regrind from identical container scrap, 1–3 wt% color concentrate, 0.5–1.5 wt% antistatic masterbatch, and 2.0–2.5 wt% carbon black or ultraviolet stabilizer masterbatch when outdoor storage is specified. Design-type qualification is performed under Chapter 6.1 of the UN Model Regulations, with drop testing at -18 °C for liquid-filled containers, hydraulic pressure at 100 kPa or 1.5× vapour pressure per UN 6.1.5, leakage proofness per UN 6.1.6, and stack loading at 40 °C for 28 days. Terminal products include 20 L jerricans, 25 L stackable carboys, 200 L tight-head drums, and 250 L open-head pails for corrosive and flammable liquid classes under ADR/RID packaging instructions.

Automotive barrier-layer coextrusion of DEF reservoirs and plastic fuel tanks

In coextrusion blow moulding, Idemitsu HDPE CALP H100 is evaluated as HDPE substrate layers rather than as a monolithic structure because fuel permeation and Diesel Exhaust Fluid compatibility require ethylene-vinyl alcohol barrier and adhesion layers. The process uses a multi-extruder accumulator head with 6 or more extruders, individual barrel temperatures 190–230 °C, die-head temperature 210–225 °C, parison programming over 100 points, final blow pressure 0.8–1.2 MPa, and mould cooling 10–20 °C. Typical layer ratios are outer HDPE layer 10–15 wt% of total wall, inner HDPE layer 15–20 wt%, regrind core 40–60 wt%, tie layers based on maleic anhydride-grafted polyethylene 3–6 wt%, and EVOH barrier 2–5 wt%; carbon black addition is restricted to the outer layer at 2.0–2.5 wt% and is excluded from the inner fluid-contact layer. Compliance for fuel tanks references UN ECE R34, while Diesel Exhaust Fluid reservoir material compatibility is evaluated under ISO 22241-3 after thermal ageing and urea exposure. Terminal products include SCR diesel exhaust fluid reservoirs, windshield washer reservoirs, and plastic fuel tanks in passenger and commercial vehicles where high environmental stress crack resistance and pinch-off weld integrity are critical.

What limits parison sag in single-head blow moulding of 500 L–5000 L water tanks?

Parison sag, not melt temperature, is the limiting variable when single-head accumulator machines produce large water storage tanks from high-molecular-weight HDPE grades. In production-scale equipment with 120 mm–150 mm extruder diameter and 30:1 L/D, the material is processed at 195–215 °C with an accumulator head capable of 50–100 kg shot capacity, a 100-point parison programmer, preblow pressure 0.03–0.08 MPa, final blow pressure 0.5–0.8 MPa, and mould cooling 12–20 °C. The formulation for weathering-grade tanks includes 2.0–2.5 wt% carbon black masterbatch, 0.02–0.06 wt% fluoropolymer processing aid to reduce melt fracture during high-output extrusion, and 20–30 wt% clean in-house regrind; antioxidant top-up of 0.05–0.15 wt% is added when regrind fraction exceeds 25 wt%. Structural verification is performed under EN 13575:2012 for static thermoplastic tanks, with impact resistance tested to ISO 179-1, tensile yield to ISO 527-2, and density to ISO 1183-1. Terminal products include 500 L agricultural dosing tanks, 1000 L rainwater harvesting vessels, and 5000 L vertical storage tanks for non-potable water, process effluents, and auxiliary chemical dosing.

In heavy-gauge sheet extrusion, the downstream route to thermoformed material handling products depends on maintaining sheet gauge uniformity and low frozen-in stress before vacuum forming. Production runs on 120 mm single-screw extruders with 30:1 L/D use a melt temperature of 195–220 °C, flat-die gap 2.5–12.0 mm, three-roll stack temperature 70–90 °C, and haul-off speeds controlled to 0.2–1.0 m/min for thick-section products. Sheet forming is performed at surface temperatures of 185–210 °C, at vacuum levels -0.06 to -0.09 MPa, and with mould temperatures 15–25 °C; measured shrinkage after forming is held below 1.5% across the part length. Formulation addition ratios for heavy-gauge outdoor components are 2.0–3.0 wt% carbon black masterbatch, 0.15–0.25 wt% antioxidant masterbatch, and up to 30 wt% reused edge trim; when deep-draw features exceed 2:1 draw ratio, ethylene-octene impact modifier is added at 5–15 wt% only after notched impact retention is verified on trial plaques under ISO 179-1. Pallet performance is verified under ISO 8611-1:2011 for payload, racking, and fork-pocket load cases, with tensile properties assessed by ASTM D638-14. Terminal products include two-way and four-way entry pallets, separator boards, battery trays, and dunnage used in automated storage and retrieval systems.

When HDPE CALP H100 moves through flat-die geomembrane sheet extrusion in 0.75 mm–3.0 mm gauge

Flat-die extrusion of geomembrane sheet uses the grade’s high melt strength to stabilize draw-down from a 2.0–3.0 mm die gap to finished thicknesses between 0.75 mm and 3.0 mm. On 120 mm single-screw extruders with 30:1 L/D and screen packs at 80–120 mesh, melt temperature is maintained at 210–230 °C, die-head pressure 20–30 MPa, roll-stack temperature 75–95 °C, and line speed 1.0–4.0 m/min depending on selected gauge. The geomembrane formulation requires 2.0–3.0 wt% carbon black with particle size below 25 nm, 0.3–0.6 wt% hindered phenolic antioxidant package, and 0.2–0.5 wt% ultraviolet stabilizer; clean in-house regrind is limited to 20 wt% because layer-thickness uniformity and the GRI GM13 oxidation-induction-time requirements become difficult to hold above that fraction. Qualification testing follows GRI GM13 for high-density polyethylene geomembranes and ASTM D3350 cell classification, with tensile yield under ISO 527-3 or ASTM D6693, tear resistance under ISO 34-1, oxidation-induction time under ASTM D3895 at 200 °C, and ESCR under ASTM D1693 Condition C. Published data for this specific configuration is limited, so each plant trial must confirm gauge variation below ±8% and carbon black dispersion no worse than 2.0 on the ISO 11420 rating. Terminal products include landfill and pond liners, secondary containment geomembranes, and canal lining panels.