[PEEK Screws M2-M12] Replacing Metal Screws to Prevent Salt-Induced Corrosion and Reduce Total Cost

Thailand's plants face high humidity and salt exposure year-round, driving up maintenance costs through corrosion of metal parts. This article outlines how replacing metal screws with PEEK (Polyether Ether Ketone) screws — rated for continuous use up to 240°C — can address corrosion and reduce total cost.

Table of Contents

• The Limits of Rust Prevention | Why Metal Screws Corrode in Thailand
• Heat Resistance up to 240°C | Criteria for Selecting PEEK
• M2 to M12 Coverage | Replacement via Precision Injection Molding
• Case Studies and Track Record
• What Nippon Chemical Screw Can Solve

The Limits of Rust Prevention | Why Metal Screws Corrode in Thailand

Even SUS304/SUS316 can develop pitting or crevice corrosion in hot, humid conditions, especially near the coast or around acid/alkali washing processes. Once rust sets in, screw heads often can't be removed normally, forcing staff to destroy the bolt — adding labor burden.

Contact between dissimilar metals (e.g., stainless screws on aluminum) also causes galvanic corrosion. Coatings help, but tool scratches during tightening can let corrosion progress, requiring frequent replacement. Once seized by rust, removal takes considerable time, driving up total cost of ownership (TCO).

Switching to non-metallic materials — super engineering plastics with high heat and chemical resistance — breaks the corrosion cycle entirely, reducing replacement frequency and extending overall equipment lifespan.

Heat Resistance up to 240°C | Criteria for Selecting PEEK

PEEK withstands continuous use up to 240°C, performing well near drying ovens or hot cleaning solutions. Its thermal expansion differs from metal, requiring careful dimensional design, but it resists heat-induced softening and deformation well. It also meets UL94 V-0 flame retardancy (depending on thickness), suiting electrical/electronic components where safety matters.

PEEK resists most acids, alkalis, and organic solvents, except a few specialty chemicals like concentrated sulfuric acid — useful where metal fails, such as corrosive gas ducts or chemical cleaning equipment, extending replacement cycles.

The key decision factor is load combined with temperature: plastic screws have lower tensile strength than metal, so torque and stress at each fastening point must be reviewed against specs (flexural strength 174 MPa, tensile strength 98 MPa) and actual site loads. With a heat deflection temperature of roughly 140–160°C (load-dependent), periodic retightening checks are advisable under high load and high temperature due to possible creep.

M2 to M12 Coverage | Replacement via Precision Injection Molding

Nippon Chemical Screw offers PEEK screws from M2 to M12, suited to precision equipment, semiconductor tools, and fine fastening points in medical devices. Founded in 1965, the company applies decades of mold expertise through precision injection molding for stable, high-accuracy mass production.

The company focuses on injection molding over machining, as it generates less waste and enables high-volume production — lowering per-unit cost, which matters for an expensive material like PEEK. This suits facilities using many screws or requiring frequent replacement of consumable parts.

Stock exceeds 3,000 standard items, supplied in Thailand through trading partners, with single-unit orders supported. Sizes follow JIS standards, allowing replacement without major design changes; custom lengths and shapes are also available.

Case Studies and Track Record

In semiconductor and LCD manufacturing, PEEK is used in pure-water washing lines and etching processes with corrosive gases, thanks to its chemical resistance and purity, helping maintain yield. Its non-magnetic property also suits inspection equipment and MRI machines. In these fields, a single screw failure can cause extremely costly equipment issues, making reliable material selection critical.

In Thailand, demand is high in exhaust and gas-handling equipment, where metal screw failure in corrosive atmospheres risks toxic gas leaks. PEEK strengthens corrosion-related safety, but must be tightened to its own "twisting breaking torque" — not the original metal torque — using the company's size-specific breaking-load data.

PEEK's specific gravity (~1.3) is about one-sixth that of stainless steel (~7.9), useful for reducing moment of inertia in aerospace, drones, or robotic arms — improving mobility, shortening cycle times, and extending motor lifespan.

What Nippon Chemical Screw Can Solve

With over 60 years of experience manufacturing plastic screws, the company supports material selection and specification design for replacing metal screws, reducing corrosion risk and production downtime in Thailand's climate, backed by precision injection molding that balances quality and cost.

Beyond standard M2–M12 sizes, the company offers custom production for special shapes or strength requirements, plus guidance on strength calculation and loosening prevention. In Thailand, supply runs through major Japanese trading companies under the same quality standards as in Japan.

Key evaluation criteria: operating temperature, chemical exposure, and tensile/torque load at the fastening point. Please inquire for further details. ※ For more details, download the PDF attached to this article, or contact us via the form at the bottom of the page.

FAQ

Q1: Can PEEK screws use the same torque as metal screws?
A1: No — this risks breakage. Check the product's "twisting breaking torque" in the catalog and use roughly 50–70% of that value.

Q2: Can PEEK screws be used outdoors in direct sunlight in Thailand?
A2: PEEK has relatively good weather resistance, but prolonged UV exposure may cause minor surface degradation. For structurally critical applications, periodic inspection or a weather-resistant grade is advisable — please inquire.

Q3: Is M2 stock readily available in Thailand?
A3: Yes, standard stock starts from M2, distributed via partner trading companies with relatively short lead times. Please inquire via the form at the bottom of the page.

Key Terms

• PEEK: A super engineering plastic with 240°C continuous-use resistance, chemical resistance, and flame retardancy.
• Precision Injection Molding: Die-based molding with less waste and higher efficiency than machining, reducing cost.
• Galvanic Corrosion: Corrosion caused by a potential difference between dissimilar metals in contact, often via moisture; plastic screws act as insulation to prevent it.

※ For more details, download the PDF attached to this article, or contact us via the form at the bottom of the page.