How Plastic Jerry Cans Are Made

From HDPE Pellets to a Parison

HDPE granules are melted in a heated extruder barrel and pushed through a die head, which shapes the melt into a hollow tube called a parison. The parison hangs down between the two open halves of the mould. Wall thickness is set by the die gap, and for a jerry can the profile is programmed heavier around the area that becomes the handle, since that section carries the filled can's weight.

Mould Closing and Handle Formation

The two water-cooled mould halves close around the parison and pinch it shut at the base, sealing one end so it can hold air. The handle is not a separate part — it is formed in the same closing stroke, from the same parison, in a cavity built into the mould. Where the mould pinches the parison into the handle shape, extra wall material is needed there so the handle stays strong once the can is filled.

Blowing, Cooling and Demoulding

Compressed air is injected through a blow pin, inflating the softened parison outward until it presses against the inside of the mould and takes the shape of the container — body, base and handle together. The part is held against the cooled mould walls until it solidifies; cooling is normally the longest part of the cycle and depends mainly on wall thickness. Once solid, the mould opens and the finished can is ejected, either onto a conveyor or by a take-out arm.

Trimming and Inspection

The pinch-off seam at the base and the flash around the handle and neck are trimmed away — by hand or with in-line equipment, depending on how the line is configured for the job. Cans are then checked for wall thickness and visual defects before moving on to filling; a leak-test station can be added to the line where the application calls for it.

What Production Data Is Needed for Machine Selection?

Turning this process into the right machine for a specific jerry can needs a few pieces of information: the container drawing or a sample, the target wall weight, the material (HDPE grade), the handle and neck design, and the target output. Single-station and double-station machines suit different container sizes and output targets, and the exact configuration is confirmed once these details are known. See the Jerry Can Blow Molding Machine hub for machine options by size and application, or go straight to the 10 L to 30 L blow molding machines. Send your jerry can drawing or a sample photo and get an exact quote for the machine and the mould within 24–48 hours.