A Jerrycan is a rigid plastic or metal container used for storing and transporting liquids. Its core features are leak-proofing, impact resistance, and ease of handling. Its mainstream capacity ranges from 10 to 25 liters (20 liters being the most common), and it is widely used for fuel, chemical solvents, lubricants, and food-grade liquids (such as syrup and cooking oil).
The key difference between a Jerrycan and ordinary plastic barrels is its emphasis on portability and durability. It typically features integrated handles, leak-proof lids, and stackable storage, making it suitable for harsh environments such as outdoor, industrial, and military use.
The Jerrycan, designed by the German military during World War II in 1937, was originally intended to address the issues of leaks and inconvenience in transporting traditional metal oil barrels. Early 20-liter metal barrels used by the Allies required tools to open and were prone to deformation and leakage during transport. The German-designed Jerrycan, with its welded handles and sealed lid, can be carried by one person, opened quickly, and significantly reduced leakage. “Jerry” was the nickname the Allies used for the German army during World War II. “Can” means “container,” so the Allies dubbed the portable oil cans designed by the Germans “Jerrycans.” After the war, the name gradually became a global term.
Jerrycan Production Equipment
Core Production Equipment
Main Equipment Types and Application Scenarios
The core production equipment for Jerrycans (especially the plastic models, which account for over 80%) is the extrusion blow molding machine. Based on the degree of automation and production capacity, it can be divided into three categories:
Semi-automatic Extrusion Blow Molding Machine
Application Scenarios: Small batches of 5-10L Jerrycans (such as emergency water storage barrels), with an average daily production capacity of ≤2,000 units.
Representative Model: Zhejiang Taizhou SJ45 series (screw diameter 45mm, aspect ratio 28:1). Manual removal and deflashing are required, with a price range of 50,000-150,000 yuan per unit, making it suitable for packaging startups.
Fully Automatic Single-Station Extrusion Blow Molding Machine
Suitable for: Medium-volume production of 10-15L (e.g., food-grade lubricant barrels), with an average daily production capacity of 2,000-5,000 pieces.
Representative model: Huatai HT-75G (screw diameter 75mm, plasticizing capacity 80kg/h), equipped with an automatic notch and deflashing device, a clamping force of 100kN, and capable of processing PE and PP materials. Price: 200,000-400,000 RMB/unit.
Fully Automatic Multi-Station Extrusion Blow Molding Machine
Suitable for: 20-25L large-volume industrial-grade Jerrycans (such as chemical solvent drums), with a daily production capacity of ≥10,000 pieces.
Representative Model: 100 Series Fully Automatic High-Speed Blow Molding Machine (accumulator die, 220kg/h plasticizing capacity), dual-station design, dry cycle capacity of 150 molds/hour, and support for the MOOG 100-point wall thickness control system. Price range: ¥800,000-1.5 million per unit.
Core Equipment Configuration Compatible with Jerrycan Performance
Extrusion System
Screw: Made of 38CrMOALA nitrided steel, with an aspect ratio of 25:1-28:1 (suitable for the high plasticizing requirements of HDPE). The variable-speed screw with a mixing head ensures uniform plasticization of the raw material and prevents bubble defects in the can body.
Temperature Control: Five-stage heating with an accuracy of ±1°C prevents HDPE degradation, which can lead to a decrease in container toughness (which directly affects the impact resistance of the jerrycan).
Molding System
Die Head: Accumulator-type structure (first-in, first-out) with a die diameter ≤500mm, suitable for molding preforms for jerrycans under 25L. An optional closed-loop wall thickness control system maintains can body tolerances within ±0.1mm.
Mold Clamping Mechanism: Hydraulic double-tie rod design with a clamping force of 50-200kN (≥100kN for 20L jerrycans) ensures precise seam closing and prevents leaks at the can body seams.
Control System
Utilizes a Japanese PLC and imported electrical components, supports parameter memory (such as blow pressure and molding cycle for different jerrycan capacities), and is equipped with fault diagnosis functions to reduce the risk of production downtime.
Key Supporting Equipment
Mold System: Determines the structural accuracy of the Jerrycan
Core Requirements: Single-cavity horizontal mold (compatible with the Jerrycan’s integrated structure), made of P20 or 718H pre-hardened steel, with a cavity surface polishing accuracy of Ra ≤ 0.8μm, ensuring a smooth and odor-free can interior (meeting food-grade requirements).
Featured Design: The mold must incorporate molding features such as reinforcing ribs and anti-slip grooves. For example, the 25L Jerrycan mold features longitudinal reinforcing ribs engraved via a CNC machining center to enhance the container’s drop resistance.
Raw Materials and Auxiliary Molding Equipment
Raw Material Handling Equipment:
Mixer (200kg capacity): Mixes HDPE raw materials with antistatic agents/masterbatch to meet the antistatic requirements of the fuel Jerrycan;
Dryer: For hygroscopic raw materials (such as modified PP), ensures a moisture content of ≤ 0.05% to prevent pinholes in the can.
Molding Auxiliary Equipment:
Air Compressor (1.6m³/1.0MPa): Provides stable blow pressure (0.6-0.8MPa) to ensure uniform can wall thickness;
Cooling System: Dual cooling system, air ring and in-mold water cooling, shortens molding cycle (molding cycle for a 20L Jerrycan can be controlled within 30 seconds).
Post-Processing and Testing Equipment
Deflashing Machine: Fully automatic hydraulic type, suitable for removing flash from Jerrycan can mouths and handles, with an accuracy of ±0.5mm;
Sealing Tester: Uses negative pressure to test the leakage rate (≤0.1kPa/min) to ensure compliance with leak-proof performance standards;
Drop Tester: Simulates a 1.5-meter drop to verify the impact resistance of the can (meets Jerrycan’s core safety requirements).
Comparison of Mainstream Chinese and Foreign Machine Models
Applicable Capacity
Chinese Models (e.g., JWZ-BM, Huatai HT-75G): 5-25L
European and American Models (e.g., Battenfeld, KraussMaffei): 10-100L (including large industrial tanks)
Core Accuracy
Chinese Models: Wall Thickness Tolerance ±0.1mm, Leakage Rate ≤0.3kPa/min
European and American Models: Wall Thickness Tolerance ±0.05mm, Leakage Rate ≤0.05kPa/min
Productivity
Chinese Models: Dual-Station 1,900 pieces/hour (20L)
European and American Models: Multi-Station 3,000 pieces/hour (20L)
Price Range
Chinese Models: 200,000-800,000 RMB/unit
European and American Models: 3-8 million RMB/unit =
Core Advantages
Chinese Models: High cost-effectiveness, short mold adaptation cycle (within 30 days)
European and American Models: Strong high-end customization capabilities, compatible with high-temperature-resistant engineering plastics (such as PA66)
Production Process and Equipment Adaptation Logic
Raw Material Preparation: HDPE granules are mixed with additives in a mixer → dewatered in a dryer (Equipment: Mixer + Dryer);
Plasticizing and Extrusion: The screw heats and plasticizes the raw material → the die extrudes the tube preform (Equipment: Extrusion Blow Molding Machine Extrusion System);
Mold Closing and Blowing: The mold is closed → compressed air is used to inflate the tube preform → water cooling is used to set the shape (Equipment: Extrusion Blow Molding Machine Molding System + Air Compressor);
Post-Processing and Testing: Automatic deflashing → Sealing test → Drop test (Equipment: Deflashing Machine + Testing Equipment)
Key Principles for Equipment Selection
Small-batch general-purpose jerrycans (5-10L): Prioritize Chinese semi-automatic machines to limit initial investment;
Medium-batch industrial-grade jerrycans (15-20L): Utilize Chinese fully-automatic dual-station machines (such as the Apollo ABLB 90) to balance production capacity and cost;
High-end customized jerrycans (such as military fuel tanks): Utilize European and American multi-station machines to ensure precision and corrosion resistance.
Jerrycan Production Process
Core Process
Jerrycan’s “seamless hollow structure + impact resistance” requirements dictate its core production process, extrusion blow molding (accounting for over 90%). This process achieves integrated molding through “molten raw material extrusion into a tube blank → compressed air inflation to set the shape.” This perfectly matches the seamless requirements of the jerrycan can body and handles (some integrated designs). Furthermore, the mold allows for precise control of key features such as ribs and seals. Compared to injection molding, it is more suitable for mass production of medium-sized hollow containers (10-25L).
Full Process Analysis (Using a 20L HDPE Industrial Jerrycan as an Example)
Raw Material Preparation: Laying the Foundation for Product Performance
Raw Material Selection
Core Base Material: Select high-density polyethylene (HDPE) with a melt index (MI) of 0.3-1.0 g/10 min (190°C/2.16 kg). This low MI ensures raw material toughness, meeting the Jerrycan’s requirement of withstanding a 1.5-meter drop without breaking.
Additive Addition:
Antistatic Agent (such as quaternary ammonium salts): Add 0.5%-1% to meet the anti-static requirements of the fuel jerrycan (surface resistance ≤ 10¹¹Ω).
Antioxidant (such as 1010): Add 0.1%-0.3% to prevent HDPE degradation during processing.
Masterbatch: Add as needed (e.g., blue, black) to ensure uniform color.
Raw Material Pretreatment
Mixing: Use a 200kg capacity mixer (corresponding to the previously mentioned equipment) for low-speed mixing for 15-20 minutes to ensure uniform dispersion of the additives and HDPE granules. This prevents localized over-additive buildup, which can lead to brittle can bodies.
Drying: If the raw material moisture content is greater than 0.05% (e.g., hygroscopic modified PP), it must be dried in a hot air dryer (80-90°C, 2-3 hours) to prevent bubbles during plasticization, which can lead to pinhole leaks in the can body.
Plasticizing Extrusion: Converting the solid raw material into a formable melt.
Equipment: This process relies on the extrusion system (screw + heating barrel) of an extrusion blow molding machine. The China Huatai HT-75G model (screw diameter 75mm) is used as an example.
Process Parameter Control:
Screw Speed: 30-50 rpm. Too high a speed can cause excessive shear degradation of the HDPE, while too low a speed can lead to uneven plasticization.
Heating Zone Temperature (5-stage control):
Feeding Zone: Temperature range 140-160°C. This preheats the raw material to prevent solid particle blockage.
Compression Zone: Temperature range 170-190°C. This compacts the raw material, removes air, and achieves initial plasticization.
Homogenization Zone: Temperature range 180-200°C. This ensures complete plasticization and a uniform melt (stable melt index).
Die Zone: Temperature range 190-210°C. This controls melt flowability and prevents die buildup.
Melt Pressure: Controlled between 15-25 MPa. Excessive pressure can lead to uneven discharge from the die and increased can wall thickness variation.
Preform Extrusion:
The plasticized HDPE melt is extruded through an accumulator die (die diameter 300-400mm, suitable for 20L jerrycans) to form a hollow preform (wall thickness 3-5mm).
Key Control: The MOOG 100-point wall thickness control system (available on high-end models) adjusts the die discharge in real time to ensure a circumferential wall thickness deviation of ≤0.2mm, preventing cracking of the can body due to localized thinning after subsequent inflation.
Molding and Finalization: Conversion from preform to jerrycan shape
Preform Droop Control:
After the preform is extruded from the die, it is steadily pulled downward by a pulling device (such as a rubber roller) at a speed of 50-80mm/s to prevent deformation (e.g., thickening at the bottom and thinning at the top) due to its own weight, which could affect the final dimensional accuracy.
Mold Closing and Air Blowing:
Mold Closing: When the tube reaches the mold cavity height (approximately 500mm for a 20L Jerrycan), the hydraulic clamping mechanism (clamping force ≥ 100kN) rapidly closes the mold, enclosing the tube in the cavity. The mold cavity must be pre-cooled to 30-40°C to initially cool the tube surface and prevent it from sticking to the mold.
Air Blowing: Compressed air at 0.6-0.8MPa (provided by a 1.6m³/1.0MPa air compressor) is introduced through the mold cavity’s air port for 2-3 seconds, inflating the tube until it adheres tightly to the mold cavity wall, forming the Jerrycan can body, integrated handle (designed), and ribs.
Pressure Control: The air pressure must be stable. Too low a pressure can result in a loose fit and unclear ribs. Too high a pressure can cause the can mouth to crack.
In-Mold Cooling and Shaping:
After the air blowing is completed, the in-mold water cooling system (corresponding to the cooling system) is activated. Cooling water at 15-20°C is introduced through the cooling channels of the mold cavity for 8-12 seconds (using a 20L jerrycan). This lowers the product temperature from 180°C to below 60°C, allowing for rapid shaping.
Cooling time control: Too short a time can lead to product shrinkage and deformation (e.g., reduced can neck diameter), while too long a time can reduce production efficiency (a dual-station machine can reduce production capacity from 1900 pieces/hour to 1500 pieces/hour).
Mold Opening and Part Removal: Separating the product from the mold
Mold Opening: After cooling is complete, the mold clamping mechanism opens the mold smoothly at a speed of 100-150mm/s to prevent the product from impacting the mold due to inertia and causing damage to corners.
Part Removal:
Semi-automatic models: Manual part removal using a suction cup tool is suitable for small-batch production (≤2,000 pieces per day).
Fully automatic models (such as the dual-station 100 series): A robotic arm removes the part (response time ≤0.5 seconds) and then transfers the part to a post-processing station, supporting a daily production capacity of ≥10,000 pieces.
Post-Processing: Improving product appearance and precision
Deburring:
Equipment: A fully automatic hydraulic deburring machine (accuracy ±0.5mm) removes burrs (1-2mm thick) from the can mouth and handle base.
Processing: Customized cutting tools are used to cut along the parting line, ensuring a smooth cut and preventing burrs from affecting subsequent sealing cap installation.
Trimming and Grinding: Lightly sand the cut edges after deburring (e.g., using 800-grit sandpaper) to remove burrs and prevent scratches during handling. For food-grade jerrycans, clean the grinding dust with pure water to avoid contamination.
Handle Welding (Non-Integrated Design): Some jerrycan handles are split. These handles must be welded to the can body at the designated location using an ultrasonic welder (20kHz frequency, 0.3-0.5MPa pressure). The weld strength must meet a tensile strength of 500N or greater without breaking.
Finished Product Inspection: Ensure compliance with applicable standards
Appearance Inspection: Manual or visual inspection is used to inspect the can body for scratches, bubbles, deformation, and to ensure the ribs are clear and the color is uniform.
Dimensional Inspection: Use calipers to measure the can mouth diameter (tolerance ±0.5mm), can body height (tolerance ±1mm), and wall thickness (tolerance ±0.1mm) to ensure compatibility with the sealing lid and stacking.
Sealing Test:
Equipment: Negative pressure sealing tester (equivalent to the previous testing equipment).
Process: After sealing the jerrycan, vacuum the can to -50kPa for 30 seconds. If the pressure rises ≤0.1kPa/min, the can is considered leak-proof.
Performance Testing:
Drop Test: Free drop from a height of 1.5 meters (can filled with water) onto a concrete floor. No cracks or leaks are observed.
Compression Test: 500N pressure is applied to the can top for 1 minute. Can deformation is ≤5mm.
Specialized Testing: Food-Grade Jerrycan Volatile organic compounds (VOCs) must be tested to ≤10mg/kg, in compliance with FDA 21 CFR 177.1520. Jerrycan fuel must also be tested for anti-static properties (surface resistivity ≤10¹¹Ω).
Comparison of Process Differences: Control Accuracy Comparison between Chinese and Foreign Machines
Temperature Control Accuracy
Chinese Models (e.g., JWZ-BM): ±1°C
European and American Models (e.g., Battenfeld, Germany): ±0.5°C
Impact on Products: European and American models offer smaller wall thickness deviations (≤0.05mm)
Blowing Pressure Control
Chinese Models: Fluctuation ±0.05MPa
European and American Models: Fluctuation ±0.02MPa
Impact on Products: European and American models offer more uniform mold adhesion and clear ribs
Cooling Time Control
Chinese Models: ±0.5 second tolerance
European and American Models: ±0.2 second tolerance
Impact on Products: European and American models offer lower shrinkage (≤1%)
Inspection Integration
Chinese Models: Requires separate inspection equipment
European and American Models: Integrated online wall thickness inspection Sealing Detection Module
Product Impact: European and American models have a lower defective rate (<0.5%)
Process Optimization Directions (Targeting Different Needs)
Efficient Production: For large-volume 20L jerrycans, a “dual-station extrusion blow molding machine + robotic arm automatic part removal” was used to reduce the molding cycle from 30 seconds to 25 seconds, increasing daily production capacity by 20%;
High-End Customization: Military jerrycans require a “low-temperature resistance modification process” (adding 5%-10% POE elastomer to HDPE) to ensure they withstand drops to -40°C without breaking;
Environmental Requirements: Utilizing “recyclable HDPE raw materials + solvent-free masterbatch,” the process reduces cooling water usage (e.g., closed-loop water cooling system) to reduce energy consumption and pollution.
Materials and Requirements for Jerrycan Production
Core Base Material: Determines the Basic Performance of the Container
Leading Base Material: High-Density Polyethylene (HDPE)
HDPE is the core raw material for over 90% of Jerrycan products. Its performance adaptability stems from three key characteristics:
Structural and Mechanical Advantages
The molecules are densely packed linearly, with a density of 0.941-0.965 g/cm³ and a crystallinity of 70%-80%. This gives the container excellent impact resistance (surviving a 1.5-meter drop without breaking) and compression resistance (deformation ≤5 mm under 500 N pressure).
High molar mass (HMW) grades are preferred, with a melt index (MI) controlled between 0.3-1.0 g/10 min (190°C/2.16 kg). The low MI ensures toughness after molding and prevents brittle cracking in low-temperature environments.
Chemical Stability
It is resistant to most acids, bases, and organic solvents (such as ethanol and motor oil), but has limited resistance to strong oxidizing media (such as concentrated nitric acid). It is suitable for storage of industrial chemicals, fuels, and food in a variety of scenarios.
Food-grade HDPE must comply with FDA 21 CFR 177.1520, with a volatile organic compound (VOC) level of ≤10mg/kg, ensuring no odor transfer.
Processing and Environmental Properties
The melt temperature is 130-200°C, suitable for the five-stage temperature control requirements of extrusion blow molding. The mold shrinkage is stable (1.5%-3.0%), facilitating accurate control of can dimensions.
The recycling mark is “02,” indicating reusability and conforming to environmentally friendly packaging trends.
Modification and Composite Substrates: Meeting Special Needs
Barrier Modified HDPE
By incorporating Quoral® barrier resin (containing polyamide PA) into a single-layer laminar structure, its oxygen and solvent barrier properties are five times higher than those of traditional fluorinated HDPE, making it a suitable alternative to glass and metal containers for storing highly permeable chemicals (such as solvents and adhesives).
Typically used in UN-certified Jerrycans (e.g., grade 3H1), it meets the permeation control requirements for aviation chemical transport.
Low-Temperature Modified HDPE
The addition of 5%-10% POE elastomer (polyolefin elastomer) disrupts molecular crystalline regularity, ensuring that the container maintains impact resistance at -40°C, meeting the requirements of military and cold-region operations.
Reinforced Modified HDPE
By incorporating 10%-20% glass microspheres or carbon fibers, the container body is enhanced in rigidity and temperature resistance (raising the operating temperature from 60°C to 80°C), making it suitable for high-temperature liquid storage.
Functional Additives: Precisely Control Material Properties
Core Additive Types and Functions
Antioxidants
The mainstream choice is 1010 (hindered phenols), added at a dosage of 0.1%-0.3%. By capturing free radicals, they prevent thermal oxidative degradation during HDPE processing, extending the container’s service life.
When combined with a phosphite-based auxiliary antioxidant, antioxidant efficiency can be increased by 30%.
Antistatic Agents
Quaternary ammonium salts are primarily used, added at a dosage of 0.5%-1%. These migrate to the surface to form a conductive layer, reducing the surface resistance of the can to ≤10¹¹Ω, preventing the risk of static electricity accumulation when storing flammable liquids such as fuel.
Masterbatches and Colorants
Solvent-free masterbatches (such as carbon black and titanium dioxide) are used at a dosage of 2%-5% to ensure uniform color and meet food safety requirements (e.g., white for dairy packaging, black for light-blocking and protecting photosensitive liquids).
Natural masterbatches can achieve a translucent can surface, making it easier to observe the liquid level inside.
Processing Aids
Zinc stearate (addition level 0.1%-0.2%) acts as a lubricant to reduce friction between the melt and the mold, preventing scratches and buildup on the can body.
Avoiding Additive Selection
Food-grade jerrycans prohibit the use of colorants containing heavy metals (such as cadmium red) and must pass EU 10/2011 plastic contact material certification.
Fuel cans prohibit the use of additives containing polar groups (such as certain ester plasticizers) to prevent additive leaching and contamination of the fuel.
Supporting Component Materials: Ensure Sealing and Usability
Sealing System Materials
Bottle Cap Base Material
Polypropylene (PP, recycling symbol “05”) is the mainstream material. It has superior rigidity to HDPE and strong creep resistance, making it suitable for sealing requirements during repeated twisting.
Fluorinated PP is used in special applications to improve resistance to strong solvents.
Sealing Liner Material
Food-grade: Cross-linked polyethylene (XLPE) liner, odorless and grease-resistant.
Industrial: Ethylene propylene diene monomer (EPDM) liner, acid and alkali-resistant, with a sealing pressure of up to 0.8 MPa.
Structural Reinforcement Materials
Split Handle: Glass fiber-reinforced PP (20% glass fiber content) with a tensile strength of ≥30 MPa, meeting a 50 kg load capacity.
Reinforcement Insert: Military Jerrycans can be embedded with stainless steel wire (0.5-1 mm diameter) to enhance the can’s deformation resistance.
Mold Material: Adaptable to molding process requirements.
Core Cavity Material
Predominantly used are P20 or 718H pre-hardened steel with a hardness of HRC 28-35. After CNC machining, the surface is polished to an accuracy of Ra ≤ 0.8 μm, ensuring a smooth, burr-free interior.
For large-scale production (daily output ≥10,000 pieces), H13 hot-work die steel is selected, offering 50% increased wear resistance and a mold life of up to 500,000 cycles.
Auxiliary Structural Materials
Cooling channels utilize copper inserts, which have a thermal conductivity five times that of steel, accelerating in-mold cooling and shortening molding cycles.
Guide columns utilize SUJ2 bearing steel, achieving a hardness of 58-62 HRC after surface quenching to ensure mold clamping accuracy.
Key Logic for Material Selection
Adaptation Based on Application Scenario
Food-Grade Jerrycan
Base Material: FDA-certified HDPE (e.g., ExxonMobil HTA 108);
Additives: Solvent-free masterbatch + food-grade antioxidant (e.g., Irganox 1076);
Seal: XLPE liner + PP cap.
Industrial Chemicals Jerrycan
Base: HDPE + Quoral® Barrier Resin;
Additives: Antistatic Agent + Chemical-Resistant Colorant;
Seal: EPDM Liner + Fluorinated PP Cap.
Fuel Jerrycan
Base: Antistatic Modified HDPE;
Additives: Quaternary Ammonium Antistatic Agent + Carbon Black Masterbatch;
Seal: Nitrile (NBR) Liner, Fuel-Resistant.
Cost-Performance Balance
Economical (Small-Batch, General-Purpose): Pure HDPE + Basic Additives, P20 Steel for Molds;
High-End (Customized Industrial Grade): Modified HDPE + Compound Additives, H13 Steel for Molds. While the cost increases by 30%-50%, the product qualification rate increases from 95% to 99.5%.
