Crane Configuration Solutions for Plastics Machinery Manufacturing
Plastic machinery manufacturing is configured across four categories: injection molding, extrusion, blow molding, and recycling lines. For injection molding clamp units, the QD Type handles 10–30 t; for extruder screws, the LD Type with a three-point bracket prevents bending (5–10 t); for blow molding die heads, the LD/LH Type covers 5–10 t; and for recycling lines, the LD Type handles 5–10 t. Complete plant solutions range from 100,000 to 500,000 CNY (approx. $14,800–$74,200).
Injection Molding Assembly: Heavy Clamp Unit Hoisting
The injection molding clamp unit (platens + tie bars + ejector) weighs 10–30 t, with platen parallelism held to ≤0.02 mm/300 mm. The recommended solution is the QD Type (10–30 t) with variable frequency dual-speed control (8/2 m/min) and anti-sway. The injection unit ranges from 2–8 t, and the screw requires frequent replacement.
Tie bars (guide rods) are the critical components connecting the fixed and moving platens. They range from 100–500 mm in diameter, 3–10 m in length, and weigh 200–3,000 kg each. Parallelism across all four tie bars must be ≤0.03 mm/m. The crane must transfer tie bars from the machining area to the assembly area and then thread them through the platens. Kelude cranes in the injection molding zone come standard with a dedicated C-Hook for tie bars (polyurethane liner), cutting single-bar lifting and transport time by 50%.
Extruder Assembly: Anti-Bending Screw Hoisting
Screws range from 30–300 mm in diameter with an L/D ratio of 25–35, up to 10 m long — classified as slender shafts. The recommended solution is the LD Type (5–10 t) with a three-point bracket screw lifting spreader (suspension point spacing ≤2 m). The clearance between the barrel and screw is 0.1–0.5 mm.
Before inserting the screw into the barrel, the clearance between the screw and barrel (0.1–0.5 mm) must be checked. Screw straightness must be ≤0.2 mm/m. Kelude's three-point bracket screw spreader measures screw deflection during lifting and transport. The extruder gearbox and motor assembly weighs 1–5 t and is mounted at the screw tail end.
Blow Molding Assembly: Die Head and Clamp Mechanism
Multi-layer co-extrusion die heads weigh 500–2,000 kg, and clamp mechanisms range from 3–8 t. The recommended solution is the LD/LH Type (5–10 t), standard with remote control and creep speed. Wall thickness control system tolerance is ±0.01 mm.
Blow molding clamp mechanisms come in two configurations: hydraulic and mechanical. Hydraulic clamp cylinders weigh 500–2,000 kg and require synchronized calibration with the tie bars during installation. Mechanical clamp toggle assemblies weigh 300–800 kg. Kelude cranes in the blow molding zone provide coverage over both the clamp mechanism and die head — the two critical work areas.
Plastic Recycling Lines: Crusher Rotor Replacement
Crusher rotors weigh 2–5 t, and screen baskets range from 200–500 kg. The recommended solution is the LD Type (5–10 t). Pelletizer die plates weigh 200–500 kg, with a replacement interval of 2–4 weeks.
Shredder knife rotors on plastic recycling lines require frequent replacement (every 1–3 months). Rotors weigh 1–3 t, and screen baskets range from 200–500 kg. Kelude cranes are positioned above the crusher with dedicated clearance for rotor hoisting, allowing the crane to reach the rotor extraction point directly.
injection molding machine QD Type10-30t Formworkparallelism | Extruder LD Type5-10t three-point bracket | blow molding machine LD/LH5-10t Die Head |
Recycling Line LD Type5-10t rotor | screw Lifting spreader three-point bracket Spacing≤2m | total plant investment 10-5010K |
Crane Configuration Table for Plastics Machinery
| Equipment | Model | tonnage | Core | Lifting spreader | investment |
|---|---|---|---|---|---|
| Injection Molding | QD Type | 10-30t | Formwork | Spreader Beam | 20-5010K |
| Extrusion | LD Type | 5-10t | screw | three-point bracket | 10-2510K |
| Blow Molding | LD/LH | 5-10t | Die Head | remote control Creep speed | 10-2510K |
| Recycling | LD Type | 5-10t | rotor | C-Hook | 10-2010K |
Kelude Heavy Industry covers the full spectrum of plastics machinery—injection molding, extrusion, blow molding, and recycling. Our three-point bracket anti-deflection solution for extruder screws is a signature technology, already deployed at companies such as Haitian Plastics Machinery.
large tonnage Injection Molding QD Type10-30t+variable frequency dual-speed+anti-sway control | screw Anti-Deflection Three-Point Adjustable Bracket Type,10mscrew Zero Deflection | Full Rangecoverage Injection Molding/Extrusion/Blow Molding/Recycling |
FAQ: Injection Molding & Extrusion Lifting Solutions
Q: How do you keep the injection molding machine clamping unit level?
A: We recommend a three-point adjustable spreader beam paired with tension sensors. Kelude's intelligent spreader beam system provides real-time display of load at each lifting point, maintaining mold platen levelness within ≤0.3mm/m.
Q: Why shouldn't wire rope be used to lift an extruder screw?
A: Single-point lifting with wire rope creates a bending moment. For a 10m screw, this can reach 500N·m during lifting and transport, which can easily cause the screw to bend. A three-point bracket lifting spreader distributes the load evenly, reducing the bending moment to zero.
Q: What precautions should be taken when hoisting a multi-layer co-extrusion blow molding die head?
A: The die head flow channel surface has a mirror finish of Ra≤0.2μm, and the tilt angle during lifting and transport must not exceed 3°. We recommend a nylon protective cover with a spreader beam. Kelude offers a dedicated protective lifting spreader solution for die heads.
Q: Why use a C-Hook for lifting injection molding machine tie bars?
A: Tie bars range from 3-10m in length and weigh 200-3000kg each. A C-Hook allows horizontal lifting and transport of a single tie bar through the platen bore. Kelude C-Hooks come with a polyurethane liner (thickness ≥10mm) to prevent scratching.
