Plastic profile extrusion is a manufacturing process that produces long, continuous plastic shapes with a consistent cross-section. Think of a pasta machine you push dough through a shaped hole and get a continuous length of pasta with that shape. Plastic extrusion works the same way, but with melted plastic and metal dies.
The extrusion process has six main stages.
Almost any 2D cross-section shape can be extruded. Common profile types include:
Simple shapes with no hollow sections. Strips, bars, rods, and flat sections.
Profiles with one or more hollow chambers inside. Cable ducts, structural channels, and window profiles are often hollow to save material and add stiffness.
C-shapes, U-channels, L-angles, T-profiles, and other open cross-sections.
Profiles with soft sealing lips, flexible fins, or hollow bulb seals.
Two materials extruded together in a single pass for example, a rigid PVC body with a soft TPE sealing lip.
Most thermoplastics can be extruded. At PlasCity, we regularly extrude:
Read our Material Selection Guide to understand which material is right for your application.
While most thermoplastics follow the same basic extrusion process, each material has its own processing characteristics, applications, and design considerations. Here is what you need to know before ordering.
PVC (Polyvinyl Chloride) is the most commonly extruded plastic and accounts for the majority of plastic profiles made worldwide. It comes in two main forms:
ABS (Acrylonitrile Butadiene Styrene) is a rigid, impact-resistant engineering plastic with an excellent surface finish. It is harder and more dimensionally stable than PVC at elevated temperatures, making it preferred for automotive, electronics, and industrial applications.
HDPE (High Density Polyethylene) is a tough, chemically resistant plastic well suited for outdoor, water-contact, and food-contact applications. It has one of the best long-term weather resistance profiles of any commodity plastic.
An extrusion die is the custom metal tool that gives your profile its shape. It is a precision-machined steel plate with a hole (or set of holes for multi-cavity dies) that matches your profile cross-section exactly.
At PlasCity, we design and machine all our extrusion dies in-house. A standard extrusion die takes 2 to 4 weeks to make. Complex dies or dies requiring polished surfaces may take longer.
When changes are needed to a profile, we can often modify the existing die rather than making a completely new one. This can save time and cost if the changes are minor.
The die is made once and then used for all future production of that profile. Die costs are a one-time investment you pay for the die once, and then only pay per-metre for the plastic produced.
Tolerances in plastic extrusion depend on the material, wall thickness, and profile complexity. Typical tolerances:
| Measurement | Typical Tolerance |
|---|---|
| Overall width and height | ±0.1mm to ±0.3mm for standard profiles |
| Wall thickness | ±0.1mm to ±0.2mm |
| Straightness | Max 1mm per metre on most profiles |
| Length (when cut) | ±1mm on most cutting methods |
PVC and rigid materials hold tolerances better than flexible materials. If you have tight tolerance requirements, mention them when requesting your quote so we can confirm whether they are achievable.
At PlasCity, our minimum order quantity (MOQ) for extrusion profiles is 3,000 to 5,000 metres per profile shape. This is because each production run requires setup time to thread the profile through the machine and stabilise the process.
For very thin or complex profiles, the MOQ may be higher because setup takes longer relative to production output. For very large profiles with a lot of material per metre, the MOQ in metres may be lower.
On repeat orders (where the die is already made and approved), we may be able to accommodate smaller quantities depending on current production schedules.
For a completely new profile (new die):
| Stage | Typical Duration |
|---|---|
| Die design and quotation | 2 to 3 business days |
| Die manufacturing | 2 to 4 weeks |
| Trial production and sample making | 1 to 3 days |
| Sample shipping to you | Depends on location |
| Your sample approval | Depends on you |
| Bulk production | 1 to 3 weeks depending on quantity |
Total for a first order: typically 4 to 8 weeks from quote approval to delivery. For repeat orders, lead time is usually just the production time (1 to 3 weeks).
To place an extrusion order with PlasCity:
DWG, DXF, PDF, or STEP files work well. If you do not have drawings, a photo with dimensions is a good start.
Tell us the plastic type and your colour requirement (RAL, Pantone, or a colour sample).
Tell us how many metres you need and how long each piece should be cut.
Within 1 to 2 business days, we send you the die cost and per-metre price.
When you approve the quote, we begin making the die.
We produce samples and send them to you for approval before bulk production.
After sample approval, we produce the full order and deliver.
Ready to start? Request a free quote or WhatsApp us with your requirements.
Plastic extrusion is a continuous manufacturing process where solid plastic pellets are melted and pushed through a shaped metal die, producing a part with a fixed cross section along its entire length. The plastic cools and hardens into its final shape as it leaves the die. It is one of the most common ways to make long, uniform plastic parts such as pipes, seals, window profiles, and cable trunking.
The process runs in five steps. First, feeding, plastic pellets or granules are loaded into a hopper. Second, melting and conveying, a rotating screw inside a heated barrel moves the pellets forward while melting them into a smooth liquid. Third, filtering, the melted plastic passes through a screen pack and breaker plate that remove contaminants and build even pressure. Fourth, shaping, the filtered melt is forced through a custom die that gives it the target cross section. Fifth, cooling and cutting, the shaped profile is cooled and calibrated to hold its shape, then cut or coiled to length.
There are four main types. Profile extrusion makes continuous parts with a fixed cross section, such as seals, channels, and trims. Sheet and film extrusion makes flat, wide continuous sheets. Pipe and tube extrusion makes hollow circular profiles. Coextrusion combines two or more materials through the same die in a single pass, used for products that need both a rigid core and a soft outer layer.
The main purpose of extrusion is to produce long, dimensionally consistent plastic parts efficiently and at scale, at a lower per unit cost than other processes once tooling is made. Common applications include window and door seals, pipes and tubing, cable trunking and conduit, weatherstripping, edge trims, HVAC and refrigeration gaskets, retail display channels, and structural profiles for construction.
Extruded plastic products, once cooled and solid, are inert and safe to handle under normal use, this is how PVC pipes, food containers, and window profiles are used safely worldwide every day. The manufacturing process itself requires proper temperature control and ventilation, since overheating raw material during processing can release fumes, a standard safety consideration inside any extrusion factory, not a hazard to someone using the finished product.
Processing temperature depends on the material. PVC is typically extruded around 160 to 210 degrees Celsius, HDPE around 180 to 220 degrees Celsius, PP around 200 to 250 degrees Celsius, and ABS around 200 to 250 degrees Celsius. Exact settings depend on the specific grade and profile design, temperature is calibrated per material and per die to avoid degradation.
Want to see how PlasCity puts this process to work making custom profiles? Visit our Plastic Profile Extrusion page or contact us to get started.
Send us your drawings or describe your profile. We will quote within 1 business day.