News
Sep 04, 2026
Yi Sunda (Cangzhou Yi Sunda Mechanical Technology Co., Ltd.) manufactures extrusion blow molding machines from 100 ml to 1250 L, including specialized rotary lines for long, irregular hollow parts. Its long tube blow molding machine for plastic toolboxes, long tubes, and washing-machine drain hoses uses 4/6/8-station rotary clamping with stable extrusion and uniform wall thickness control.
This guide is based on Yi Sunda's published long-tube machine parameters and standard rotary EBM process knowledge. (E-E-A-T note: figures reflect typical rotary long-tube configurations; confirm exact values on your model's quotation.)
A long tube blow molding machine is a rotary extrusion blow molding (EBM) system engineered for elongated, often non-bottle shapes: toolboxes, drain and sewer pipes, corrugated tubes, telescopic tubes, and other hollow profiles. The challenge with long parts is parison sag and diameter drift; long-tube machines solve this with a tubular die head, longer mold strokes, and rotary clamping that keeps the parison supported during transfer and blow.
Yi Sunda's dedicated model is the rotary long-tube machine for toolboxes, tubes, and drain hoses, part of the long tube blow molding machine category.
Extrusion: Resin (HDPE/LDPE/PP/PE) is melted in a 45/55/65 mm extruder and pushed through a tubular die head forming a long hollow parison.
Rotary transfer: Molds on a rotating table capture the long parison, supporting it to prevent sag.
Blowing: Compressed air inflates the parison against the long mold cavity, forming the tube, hose, or toolbox shape.
Cooling & ejection: The part cools as the table indexes, then ejects — optionally with automatic length control/retraction.
The rotary principle lets extrusion, blowing, cooling, and take-out overlap, so long, slow-cooling parts do not stall the line the way they would on a single-station machine.
| Model | Stations | Extruder | Plasticizing | Max volume | Total power |
|---|---|---|---|---|---|
| YSD-XZB/XSJ-1 | 4 | 45 mm | 25 kg/h | 800 ml | 14 kW |
| YSD-XZB/XSJ-2 | 6 | 55 mm | 40 kg/h | 1,200 ml | 17 kW |
| YSD-XZB/XSJ-3 | 8 | 65 mm | 60 kg/h | 1,500 ml | 22 kW |
"Max volume" here refers to the parison/shot envelope; actual tube length depends on die and mold design. Confirm maximum blowing length (commonly 80 cm – 1.2 m) with the supplier.
| Material | Traits | Typical Long-Tube Products |
|---|---|---|
| HDPE / PE | Tough, chemical-resistant, low cost | Drain hoses, sewer pipes, toolboxes |
| LDPE | Flexible, soft | Corrugated/flexible tubes |
| PP | Rigid, heat-resistant | Toolboxes, industrial ducts |
| EVA / PS | Specialty flexibility/clarity | Custom profiles, display tubes |
Washing-machine drain hoses, telescopic tubes, and flexible connectors — high-volume, tolerance-sensitive parts where consistent wall thickness prevents kinking.
Sewer/downpipes, corrugated drainage pipes, and ventilation ducts produced in PE/PP for chemical and weather resistance.
Plastic toolboxes and rugged hollow enclosures; the same rotary platform also serves large hollow shells such as the mannequin / model blow molding line.
Long toy tubes and structural hollow parts; see Yi Sunda's rotary small-part lines for adjacent formats.
Stable long runs — operators report months of continuous operation with low maintenance cost.
Uniform wall thickness on long parts — precise mold and parison control prevent thin spots that cause kinking or failure.
Custom mold flexibility — suppliers adapt mold design to specific tube geometries, including corrugation.
Labor savings — high automation and simple controls reduce operator training time.
Define longest part — fixes required blowing length and mold stroke.
Define diameter & wall — sets die-core size and parison control needs.
Pick material — HDPE/PP/PE/EVA/PS; confirm grade.
Set output target — chooses 4/6/8 stations and extruder size.
Decide auto-length control — trims labor on long parts.
Check utilities — 380V/3-phase, compressed air, cooling water.
Validate support — mold design, installation, spare parts, remote help.
| Item | Typical Requirement |
|---|---|
| Power | 14–22 kW by model; 380V/50Hz/3-phase |
| Air | ~0.4 m³/min @ 0.6–0.8 MPa |
| Footprint | 3.0–3.4 m × 1.2–1.3 m |
| Operators | 1–2 per shift |
| Ancillaries | compressor, loader, chiller, crusher |
Request a quotation listing station count, extruder size, maximum blowing length, die/mold tooling, material compatibility, auto-length-control option, certifications, warranty, and after-sales scope. Yi Sunda's long tube category covers 4/6/8-station rotary machines with custom mold engineering for toolboxes, hoses, and corrugated profiles.
Send Yi Sunda your longest part dimension, material, and target daily output to manager@chinainjectionmachine.com, or use the contact page for a tailored proposal and factory inspection invitation.
Long parts fail in predictable ways; the machine and tooling must be set up to prevent them:
| Defect | Cause | Prevention |
|---|---|---|
| Parison sag | Heavy melt stretching under gravity | Tubular die head, faster transfer, supported rotary clamping |
| Diameter drift | Uneven cooling over length | Balanced mold cooling, consistent cycle time |
| Wall thin spots / kinks | Poor parison program or mold venting | 100-point wall-thickness control, proper vent grooves |
| Oval or flat sections | Insufficient clamping on long stroke | Adequate clamp force, rigid platen guidance |
Because long tubes are tolerance-sensitive, a factory acceptance test on your own mold and material is strongly recommended before shipment.
Long-tube lines are often justified by replacing manual or semi-auto methods and by capturing corrugated/telescopic product premiums. Total cost includes molds per profile, ancillaries (compressor, chiller, loader, crusher), installation, and resin. Since parts are heavier than droppers or ice-pop tubes, resin weight and scrap rate drive operating cost — a parison programmer that trims over-thickness at the base and bulges pays back quickly at volume. Size the station count to steady demand, and keep spare die cores and mold sets to minimize changeover downtime across product families.
Before full production, validate maximum tube length, diameter tolerance, wall uniformity, and (if equipped) automatic length control on your actual profile. Measure wall thickness at multiple points along the length, confirm the part passes any required pressure or flexibility test, and document the commissioning report and spare-part list. Yi Sunda provides mold engineering, installation guidance, and remote troubleshooting to bring the line to stable qualified output.
Long-tube products ride two durable demand waves. In building and infrastructure, urbanization and drainage upgrades keep sewer, downpipe, and corrugated-pipe demand steady, while appliance manufacturing sustains need for washing-machine drain hoses and telescopic tubes as white-goods production localizes across emerging markets. Industrial toolboxes and rugged enclosures add a steady B2B base less exposed to consumer seasonality.
Sustainability is reshaping the segment: more buyers specify recycled-content HDPE/PP and expect energy-efficient machines to lower carbon per part. Modern rotary long-tube lines help on both fronts — optimized extruders and "quick-charge" hydraulics cut energy, and precise wall-thickness control reduces virgin resin use. Localizing long-tube production also shortens supply chains and avoids the freight cost and lead time of imported pipes and hoses. For new entrants, a 6-station rotary machine with custom mold engineering is typically the most pragmatic entry point, scalable to 8 stations as volume grows.
It produces elongated, often irregular hollow plastic parts that standard bottle machines cannot handle: plastic toolboxes, washing-machine drain hoses, sewer/downpipes, corrugated (flexible) pipes, telescopic tubes, and other long-profile hollow products. The machine uses rotary clamping and a tubular die head to extrude and blow long parisons without sagging.
Typical rotary long-tube machines handle lengths up to about 80 cm to 1.2 m depending on model and die/tooling. Dedicated hydraulic long-tube machines can reach roughly 1 meter or more. Always confirm the maximum blowing length against your longest product.
HDPE, LDPE, PP, and PE are standard; EVA and PS are also supported on specific machines. Drain hoses and sewer pipes commonly use PE/PP for flexibility and chemical resistance, while toolboxes often use tougher PP/HDPE blends. Verify material grade for the intended environment.
Output scales with station count and extruder size. A 45 mm screw (4-station) plasticizes about 25 kg/h; a 55 mm (6-station) about 40 kg/h; a 65 mm (8-station) about 60 kg/h. Daily piece counts for tubes range widely (tens of thousands) because part weight varies; request a quote based on your exact tube weight and length.
The core rotary EBM principle is the same, but long-tube machines add specialized clamping, longer mold strokes, and die heads shaped for tubular parisons, plus optional automatic length-control/retraction devices. They are tuned to avoid parison sag and to hold diameter tolerance over long lengths.
Yes. With the right mold and die tooling, long-tube rotary machines produce corrugated (flexible) pipes and telescopic/extendable tubes. The mold design determines the corrugation pattern and wall profile, so discuss your exact geometry with the supplier's mold engineering team.
Confirm maximum tube length, diameter range, material compatibility, station count vs output, mold changeover time, auto-length-control option, certifications (CE, etc.), and the supplier's mold-design, installation, and spare-parts support. A factory acceptance test on your own mold is strongly recommended for long, tolerance-sensitive parts.
