PP Grub Screw (Polypropylene Set Screw)
PP grub screw is a lightweight engineering plastic fastening component made from polypropylene (PP), designed for corrosion-free, non-conductive, and chemically resistant applications. The PP grub screw (also known as a set screw or headless screw) is widely used in electronics, chemical equipment, water treatment systems, laboratory instruments, and lightweight industrial assemblies where metal fasteners are unsuitable due to corrosion or electrical conductivity.
As a headless fastening element, the PP grub screw is fully embedded within threaded holes, allowing secure internal locking without protruding from the surface.

Product Overview
The PP grub screw is designed for internal locking applications where surface flushness and compact structure are required. It applies pressure directly through its tip to secure components such as shafts, sleeves, or plastic assemblies.
This PP grub screw is commonly used in environments requiring chemical resistance and electrical insulation. Its polypropylene structure ensures stable performance in corrosive and moisture-rich conditions.
As a specialized industrial plastic fastener, it provides a lightweight and cost-effective solution for modern OEM engineering systems.
Product Specifications
| Item | Description |
|---|---|
| Product Name | PP Grub Screw |
| Material | Polypropylene (PP) |
| Screw Type | Set Screw (Headless) |
| Drive Type | Slotted / Hex Socket (custom) |
| Tip Type | Flat / Cone / Cup Point (custom) |
| Thread Type | Metric Machine Thread |
| Diameter Range | M3–M12 |
| Length Range | 4mm–60mm |
| Color | Natural White / Black / Custom |
| Density | ~0.90 g/cm³ |
| Electrical Conductivity | Non-conductive |
| Packaging | Bag / carton / OEM packaging |
| Customization | Tip shape, size, color available |
Technical Parameters
| Parameter | Value |
|---|---|
| Tensile Strength | 25–40 MPa |
| Compressive Strength | Moderate (plastic grade dependent) |
| Density | 0.90–0.92 g/cm³ |
| Chemical Resistance | Excellent (acids, alkalis, water) |
| Heat Resistance | Up to 90°C continuous use |
| Electrical Insulation | Excellent |
| Water Absorption | Very low |
| Manufacturing Standard | Industrial OEM specification |
Materials and Manufacturing Process
The PP grub screw is manufactured using precision injection molding technology to ensure dimensional stability and consistent performance.
- Raw material selection: High-grade polypropylene resin
- Drying process: Moisture control before molding
- Injection molding: Formation of screw body
- Tip forming: Precision molding of point type (flat/cone/cup)
- Thread forming: Molded internal or external threads
- Cooling and stabilization: Ensures dimensional accuracy
- Trimming: Removal of excess flash
- Inspection: Dimensional and functional testing
- Packaging: Clean and protective packaging
Each PP grub screw is produced under strict quality control for stable performance in industrial applications.
Applications of the Product
PP grub screws are widely used in:
- Chemical equipment: Corrosion-resistant internal locking
- Water treatment systems: Pipe and valve adjustment components
- Electronics: Insulating fastening and positioning
- Laboratory equipment: Non-reactive assembly systems
- Food processing: Hygienic and corrosion-free applications
- Marine systems: Moisture-resistant mechanical locking
- Lightweight machinery: Plastic component positioning
Their non-metallic structure makes them ideal for sensitive environments.
Why Choose This Product
- Excellent chemical resistance to acids and alkalis
- Lightweight structure reduces system weight
- Non-conductive and safe for electrical use
- Headless design for compact internal locking
- Suitable for plastic and corrosion-sensitive assemblies
- Available with different tip shapes for application flexibility
- Cost-effective industrial plastic fastener
- Custom sizes and configurations available
- Ideal for OEM production environments
The PP grub screw provides a reliable solution for internal fastening in modern lightweight systems.
Why Choose Flybear
Flybear is a professional manufacturer specializing in industrial fasteners and engineering plastic fastening solutions.
- Advanced plastic injection molding capability
- Stable OEM production capacity
- Custom engineering support for special applications
- Strict quality inspection system
- Global export experience in fastener manufacturing
- Technical consultation for material selection
Flybear delivers reliable fastening solutions for chemical, electronic, and industrial applications worldwide.
Quality Inspection and Control
Strict quality control ensures consistent performance:
- Raw material resin testing
- Dimensional accuracy inspection
- Thread fit and gauge testing
- Tip geometry inspection
- Tensile and compressive testing
- Chemical resistance validation
- Heat resistance testing
- Packaging quality verification
All production follows ISO-based quality management standards.
Selection Guide
When selecting PP grub screws, consider:
- Tip type (flat / cone / cup point)
- Installation space requirements
- Chemical exposure level
- Operating temperature range
- Load and torque requirements
- Thread compatibility
Proper selection ensures stable locking performance and long-term reliability.
FAQ
1. What is a PP grub screw used for?
It is used for internal locking and positioning in corrosion-resistant systems.
2. Is PP strong enough for industrial use?
Yes, for light to medium-load applications.
3. Can it resist chemicals?
Yes, polypropylene has excellent resistance to acids and alkalis.
4. Is it electrically insulating?
Yes, PP is a non-conductive material.
5. Can it be customized?
Yes, Flybear supports full customization of size, tip, and color.
We always adhere to the philosophy of quality first and customer first, providing customers with high-quality fastener products and one-stop fastener solutions.
Contact us for quotation, customization, and technical support via Contact Us.




