Sheet Quality Decides Product Quality

In thermoforming, the finished tray can never be better than the sheet it was formed from. Thickness variation, gel particles and uneven cooling all survive the forming station and appear as weak corners, warped bases and inconsistent wall sections. This is why the extruder deserves as much attention as the former.

The SI-PE single screw sheet extruder from Shantou Longsheng Industry Co., Ltd. is built for PE sheet production, one of the three extruder families the company offers alongside its DSI-PP multilayer co-extruded sheet extruder and the LSI series PET/PLA single screw sheet extruder with drying and crystallisation system.

Why a Single Screw for PE

PE processes predictably on a single screw. The material has a wide processing window and does not demand the aggressive mixing profile that some engineering resins require. A well-designed single screw delivers:

• Stable melt pressure, which translates directly into stable sheet gauge
• Even melt temperature, avoiding the hot spots that cause thin patches
• Controlled output, so the downstream former is fed at a constant rate

Longsheng has been building plastic machinery since 1998 in Shantou City, Guangdong Province, and operates a 30,000 square metre production facility with 25 authorised patents.

Where PE Sheet Goes

PE sheet from this extruder feeds both packaging and industrial product streams:

• Packaging: trays, liners, protective interleaves and container bases
• Industrial: separators, protective covers, gaskets and fabricated components
• Agriculture and logistics: nursery components, dividers and handling aids

PE is chosen where toughness and chemical resistance matter more than optical clarity. It resists moisture, tolerates many chemicals and stays ductile at low temperature, which is why it appears in industrial trays and protective packaging rather than display packs.

Fitting the Extruder to the Line

An extruder is only useful in balance with what follows it. Longsheng matches sheet width and output to the thermoforming machine downstream, and supports the complete route from material selection through mold supply, installation guidance and operator training.

Producers running both PE and PP, or moving into PET and PLA, can draw on the full extruder range rather than sourcing each machine separately.

For more information, visit the official website: https://www.stlongsheng.com