Material comparisons
Cast nylon vs UHMW-PE (PE1000)
Both are classics for wear jobs, which is where confusion starts. They do different jobs.
Side by side
| Topic | Cast nylon (PA6G) | UHMW-PE (PE1000) |
|---|---|---|
| Density | 1.15 g/cm³ | About 0.93 g/cm³ |
| Tensile strength | About 80 MPa | About 21 MPa |
| Friction coefficient | About 0.26 to 0.42 | About 0.10 to 0.22 |
| Moisture absorption | Absorbs | Almost none |
| Stiffness | High | Low |
| Acid resistance | Weak | Good with many acids |
| Continuous temperature | About 100 °C | Lower |
| Machinability | Very good, precise parts | Soft, precise sizes hard |
When to choose cast nylon
- The part carries load
- Structural parts such as pulleys, gears and bushings
- Precisely machined holes and grooves
- Temperatures around 80 °C
When to choose UHMW-PE
- Surfaces where bulk material slides
- Silo, bunker and chute linings
- Wet and chemical environments
- Sliding with very low friction
Which for a wear plate?
Does the plate carry load or only provide sliding?
- Load carrying slide: cast nylon. See wear plates.
- Surface with material flow: UHMW-PE.
- Acidic environment: UHMW-PE leads. See chemical resistance.
Typical uses
| Use | Usually |
|---|---|
| Crane pulley | Cast nylon |
| Silo and bunker lining | UHMW-PE |
| Gear | Cast nylon |
| Chain guide, light load | UHMW-PE |
| Heavy slide plate | Cast nylon |
| Chute lining | UHMW-PE |
| Precise drilled flange | Cast nylon |
| Sliding surface in chemicals | UHMW-PE |
Machining
UHMW-PE is very soft. It cuts and mills, but holding precise sizes is hard because it flexes under heat and cutting force. Cast nylon is stiff and holds hole and groove sizes better.
Fixing
UHMW-PE can loosen in bolted joints over time because it flows under load. Its thermal expansion is high too, so long plates need slotted holes and wide washers. Cast nylon is stiffer, but it also needs expansion room.
How to compare wear
The answer depends on the environment. UHMW-PE does very well with dry bulk flow. Cast nylon can be better in high load sliding close to metal on metal.
Mixed design
You can use both in one machine. The load carrying part in cast nylon, the sliding surface in UHMW-PE. Each material works where it is strongest. We can help on the cast nylon side.
Frequently asked questions
Is UHMW-PE more durable than cast nylon?
It is very good with abrasion and impact, but carries much less load. "Durable" depends on what you mean.
Why is cast nylon stiffer?
Its modulus and tensile strength are higher. It bends much less under load.
I cannot decide, what should I do?
Tell us the job, load, speed and environment through our contact page and we will look at it together.
Figures are typical values published by manufacturers and vary with grade and test conditions. Ask us for exact values.