Product Description
Rotational molding, also known as rotomolding, rotational forming, or spin molding, is a method for producing hollow thermoplastic products. In this process, plastic material is first added to a mold, which is then continuously rotated along two perpendicular axes while being heated. Under the combined effects of gravity and heat, the plastic gradually melts and evenly adheres to the entire inner surface of the mold, forming the desired shape. After cooling, the molded product is solidified.
Rotational Molding Process Steps
Powder Heating Cooling Product
Rotating arm
Mold
Loading material Heating Cooling Demolding
Loading material: Pour the powdered raw material into the mold and close it using screws or clamps.
Heating: Heat the mold in an oven while rotating 360°. The material melts uniformly at 230–300°C and adheres to the mold surface, forming the desired shape. Heating time depends on mold material, shape, type, and weight of the material.
Cooling: After heating, move the arm to the cooling station. Cooling is typically done using air or water mist until the mold surface reaches 80–90°C.
Demolding: Stop the rotation, open the mold, and the product is complete.
Advantages of Rotational Molding
1. Low mold cost — about 1/3 to 1/4 of blow molding or injection molding molds for the same size product.
2. Strong edge strength — edges can exceed 5 mm thickness, solving thin-edge issues in hollow products.
3. Can accommodate various accessories.
4. Can produce complex shapes with wall thickness over 5 mm.
5. Can produce fully sealed products.
6. Can be filled with foam for insulation.
7. Wall thickness can be freely adjusted over 2 mm without mold modification.
8. Seamless hollow structure with adjustable wall thickness for high strength.
9. Various surface textures and colors available; UV and aging resistance treatment possible.
10.Suitable for large hollow plastic products such as playground equipment, agricultural diesel tanks,rotomolded lighting, sweepers, water tanks, and steel-lined plastic products.
Rotational Molding Equipment
Shuttle-type rotomolding machine Multi-arm shuttle-type rotomolding machine
Rotary turret rotomolding machine
Oven-type swing rotomolding machine Open-flame swing rotomolding machine
On-site Production Photos
Rotomolding production site
Rotomolding production site
Rotomolding production site
9 Key Features of Rotomolded Products
Easy to clean Wall thickness UV-resistant
Easy to clean Shockproof Health
Oxidation-resistant Good sealing Waterproof
Selected LLDPE material
Food-grade rotomolding, excellent performance
Professional Focus, Quality Casting
Enlarged details remain smooth and glossy, visible quality
Rotational molding products
Rotational molding products
Model Description
Product Applications
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| Rotomolded products | Outdoor audio housings |
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| Smart agricultural drone chemical tanks | Smart robot housings |
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| Smart electric lifebuoy housings | Rotomolded toys |
Product parameters
Rotomolding Development Materials
Integrated rotational molding offers cost advantages.
With technological advancements, rotational molding materials have expanded from traditional PP/PE to various types, capable of meeting UV resistance levels 2, 4, 6, 8, ROHS, REACH, FDA food-grade standards, etc. Their high toughness and low mold cost make them increasingly popular among manufacturers.
Product Name | Density | Melt Index | Special Properties | Applications |
PP Rotomolding Material | 0.901 | 20 | Water tanks | |
0.9 | 10 | Instrument panels, | ||
Cross-linked PE Powder | 0.93 | Gel60% | Diesel tanks, | |
0.929 | Gel70% | High-temp storage tanks | ||
0.928 | Gel80% | Fuel tanks, high-temp | ||
Reinforced PE Powder | 0.936 | 5 | Tensile strength17Mpa | Small water tanks, |
0.935 | 6 | Tensile strength18Mpa | Water tanks | |
0.938 | 3 | Tensile strength19Mpa | Special-shaped water tanks | |
0.946 | 5 | Tensile strength18Mpa | Furniture | |
0.948 | 3.5 | Tensile strength20Mpa | Surfboards, kayaks | |
0.943 | 2 | Tensile strength23Mpa | Pressure vessels | |
0.95 | 1 | Tensile strength25Mpa | Large water tanks, | |
Flame-retardant | 0.939 | 5 | UL-94 HB | |
1.02 | 7 | UL-94 V2 | Packaging boxes, | |
1.08 | 7 | UL-94-V0 | Conveyance channels, | |
Antibacterial | 0.936 | 5 | Antibacterial activity | Strollers, floating devices, |
Anti-algae | 0.94 | 4 | Anti-algae grade 0 | Marine floats |
High-gloss | 0.928 | 7 | 60° gloss 50 | Medical product covers |
Transparent PE Material | 1.21 | 25 | Transparency 90% | Lighting |
POM Rotomolding | 1.41 | 10 | Fuel tanks | |
Nylon Rotomolding | 1.14 | 11 | Fuel tanks | |
Foaming Rotomolding | 0.93 | 7 | 4× foaming ratio | Reinforced layer |
0.93 | 7 | 8× foaming ratio | Filling layer | |
High-melt PE Powder | 0.934 | 6 | Automotive air ducts, | |
0.935 | 8 | Lighting | ||
0.932 | 10 | Water tanks | ||
0.928 | 15 | Lighting | ||
Anti-freeze PE Powder | 0.936 | 5 | Low temp-20℃ | Ice storage containers |
0.934 | 5 | Low temp-40℃ | Ice tray | |
0.93 | 5 | Low temp-70℃ | Dry ice storage boxes |
Comparison: Rotomolding vs Blow Molding / Injection Molding
Rotomolding | Blow Molding | Description | |
Mold Development Cost | ★★★★★ | ★★★★★ | For the same product size, rotomolding molds cost about 1/3–1/4 of blow or injection molds. |
Design Flexibility | ★★★★★ | ★★★★★ | Rotomolding allows rotational flow forming without demolding limitations, enabling almost any complex shape. |
Failure Rate | ★★★★★ | ★★★★★ | Rotomolding is integrally formed without welding, offering strong sealing and toughness, reducing cracking and breakage risks. |
Product Lifespan | ★★★★★ | ★★★★★ | Made mainly of polyethylene, rotomolded products are corrosion-resistant and last over 10 years. |
Material Utilization | ★★★★★ | ★★★★★ | Uniform wall thickness and slightly thicker edges maximize material efficiency. No runners or gates; minimal scrap material. |
Suitable Products | Rotational molding: mainly used to make hollow, packaging and extra-large products. It has a large shrinkage rate and relatively low production capacity. | ||
Blow molding: mainly suitable for making hollow products, packaging and other special products, with a monthly output of only a few thousand sets, and its application areas are limited. | |||
Injection molding: It is mainly suitable for making products with relatively small size, with a very large monthly output. The molds and products are of very high precision and can be used in various fields. | |||
We do more than just rotational molding;
we provide service.
We Do More Than Rotomolding — We Provide Service
Customization Process
Product size Simulation design Drawing confirmation
site requirements. cost accounting. contract signing;
1 2 3
Customer Specifies Equipment Recommendation Customer Confirms Drawings
Requirements Product Simulation Design
Submit product Create Machine production,
specification rotomolding mold mold testing
4 5 6
Provide Drawing Mold Manufacturing Mass Production
Samples &
Cost Quotation
7×24 hours support Quality assurance Full-process service
Friendly Reminders
Pricing: All products are custom-made; listed prices are for reference only. Discounts available for bulk orders.
Color Difference: Products are photographed in kind, but slight color differences may occur due to angle or lighting.
Mass Production: Production begins after the deposit or full payment is received. We will communicate multiple times with the customer to ensure smooth production and product quality. Production time will be confirmed before manufacturing to meet customer requirements.
