Steel Semi Tubular Rivet

For high‑volume production lines that need fast, reliable fastening, steel semi tubular rivets from Nuote Metals offer the ideal balance. Unlike a solid rivet that requires high force and heavy equipment, the semi‑tubular design—partially hollow at the tail—reduces setting force by roughly 70% while retaining most of the shear strength. The result is a fastener that installs quickly, works with lighter tooling, and still delivers a permanent, reliable joint.

Nuote Metals cold‑heads rivets from low‑carbon steel with optional zinc plating or other finishes. With over ten years of production experience and full ISO 9001:2015 certification, our semi‑tubular rivets are trusted by automotive, HVAC, and industrial equipment manufacturers worldwide.

What Makes a Semi‑Tubular Rivet Different

The defining feature of a semi‑tubular rivet is the shallow cavity at the tail end—typically 45–55% of the barrel length. During installation, only the thin wall of this hollow section rolls outward to form the clinch. This is fundamentally different from a solid rivet, where the entire shank must deform.

For most industrial, automotive, HVAC, and hardware applications, the semi‑tubular rivet delivers more than enough strength while keeping production efficient.

Technical Specifications – Materials, Dimensions, and Finishes

Material Properties

Standard Dimensions

We manufacture steel semi tubular rivets in the following shank diameters. Head styles, head diameters, and barrel lengths vary by size and are provided as standard ranges. Custom dimensions are available upon request.

Tolerances: Shank diameter ±0.05mm, head diameter ±0.15mm, overall length ±0.15mm. Rivet length is measured from the underside of the rivet head. Custom barrel lengths and head diameters available upon request. No tooling charge for standard sizes listed above.

Head Styles Available

Surface Finishes

For outdoor or moisture‑exposed applications, we strongly recommend zinc‑plated steel semi tubular rivets.

Mechanical Data (5mm Steel Rivet, Set into 2mm Steel Sheet)

Watch How We Make Rivets

Our cold‑heading presses form rivets from wire in a single continuous sequence—drawing, cutting, heading, cavity extrusion, and trimming. The video shows the entire process from wire feeding to finished rivet ejection, with real‑time quality monitoring at every stage.

One Real Customer Example – Folding Bed Frame Assembly

This is one of many applications for semi tubular rivets. We include it to show real production use, not to suggest limitation.

A manufacturer of portable folding beds for camping and emergency relief needed a reliable, cost‑effective rivet for the scissor‑hinge joints. The folding bed frame used 1.8mm thick steel tubing. The previous solid rivets required high setting force, which occasionally deformed the tubing during assembly and slowed down their production line. The customer also wanted a rust‑resistant finish for occasional outdoor use.

Nuote Metals supplied zinc‑plated steel semi tubular rivets – 5.0mm shank diameter, 9.0mm truss head, 12.0mm barrel length – totalling 600,000 pieces for their first order. The semi‑tubular cavity reduced setting force by over 60%, eliminating tubing deformation. The wide truss head distributed clamping force evenly, preventing pull‑through. The zinc plating provided 72 hours of salt spray protection, ensuring the rivets would not rust after exposure to damp conditions.

The customer tested the rivets across 1,000 folding beds. After 5,000 folding cycles and humidity chamber testing, no loosening or rust was observed. They have since placed reorders totalling over 2 million pieces and now specify our rivets for their entire folding bed product line.

Our In‑House Inspection Equipment

We maintain a full range of calibrated inspection equipment to verify every batch of steel semi tubular rivets:

• Digital calipers – For quick dimensional checks during production
• Micrometers – For precision measurement of shank diameter and wall thickness
• 2.5D image measuring system – For full contour measurement and concentricity verification
• Profile projector (optical comparator) – For cavity depth, head angle, and edge radius inspection
• Laser micrometer – For high‑speed, non‑contact diameter measurement
• Rockwell hardness tester – For verifying raw material hardness
• Salt spray test chamber – For corrosion resistance testing of plated rivets (ASTM B117)
• Spectrometer – For material composition verification of incoming coils
• Universal testing machine – For shear and tensile strength verification

All equipment is calibrated annually by accredited third‑party labs. Inspection records are retained for five years.

Our Quality Control – One Rivet, Eight Checks

We do not rely on random sampling. Every batch of rivets passes through eight separate quality gates before leaving our factory. The principle is simple: measure early, measure often, and never assume.

• Raw material diameter check – Incoming wire is measured with a laser micrometer. Diameter tolerance: ±0.02mm. Any coil outside this range is rejected before it touches our headers.
• Raw material hardness check – A sample from each coil is tested on a Rockwell hardness tester. For low‑carbon steel, we require HRB 60–80. Too soft, and the rivet will deform during heading. Too hard, and the cavity may crack.
• First article appearance check – After tooling setup, the first 10 rivets are visually inspected under magnification. We look for cracks, flash, uneven heads, or surface marks. Any visible defect stops the press.
• First article dimensional check – The same 10 rivets are measured on an optical comparator. Head diameter, head height, shank diameter, total length, and cavity depth. All must be within drawing tolerances before production starts.
• In‑process checks – During mass production, the operator pulls 5 rivets every 500 pieces. Dimensions are verified with digital calipers and a go/no‑go gauge for cavity depth. Any drift triggers tooling adjustment.
• Test setting (trial riveting) – Every 2,000 pieces, we set 3 rivets into a representative material sample (same thickness and type as your assembly). The clinch is inspected for symmetry and tightness. No loose or cracked rivets are accepted.
• Salt spray test (if required) – For outdoor or plated rivets, we send samples to our lab for ASTM B117 salt spray testing. Zinc plating: 48–96 hours. A certificate is issued with the batch.
• Final outgoing inspection – Before packaging, every rivet passes through an optical sorting machine. Cameras check head diameter, head height, shank diameter, total length, and cavity depth. Rejects are automatically ejected. A random AQL sample (Level II, 1.0) is then pulled for manual verification.

A steel semi tubular rivet that survives all eight steps is ready to leave our factory. We keep records of every check for five years.

What Our Customers Say – Real Feedback

Our Certifications and Honors

Nuote Metals maintains the following certifications and accreditations:

• ISO 9001:2015 – Quality management system certified by TÜV SÜD
• RoHS compliance – Verified by SGS third‑party testing
• REACH compliance – SVHC declaration current
• ASTM F1941 – Zinc plating standard compliance
• SGS test reports – Available upon request for specific batches

All certifications and test reports are available upon request.

Where Steel Semi Tubular Rivets Are Used

They are the preferred choice for applications where strength, speed, and cost‑effectiveness are priorities:

• Furniture manufacturing – Folding beds, chairs, sofas, hinge assemblies, frame joints
• Automotive industry – Brake linings, clutch facings, interior trim, body panels
• HVAC equipment – Cabinet assembly, ductwork connections, fan housings
• Industrial equipment – Machinery guards, control panels, conveyor components
• Construction – Light structural connections, metal framing, architectural hardware
• Electronics – Component mounting, chassis assembly, circuit board standoffs
• Leather goods and upholstery – Belt holes, bag hardware, fabric attachments

How We Work – Practical Information

• Samples – 20–50 free pieces for standard stocked sizes (customer pays shipping)
• Trial order – 10,000 pieces recommended for first‑time validation
• MOQ – 2,000 pieces (standard sizes), 5,000 pieces (custom barrel or head style)
• Lead time (stock) – 5–7 business days
• Lead time (custom) – 10–12 business days
• Tooling charges – None for standard head styles and shank diameters (1.5–8mm)

Three Questions We Answer Often

Q1: What is the difference between a steel semi tubular rivet and a solid steel rivet? When should I choose the semi‑tubular version?

A: The fundamental difference is the hollow cavity in the tail. A steel semi tubular rivet has a shallow cavity at the tip, requiring only 25–30% of the force needed for a solid rivet of the same diameter. This makes it faster to install and gentler on surrounding materials. Solid rivets offer slightly higher shear strength (semi‑tubular retains 80–90% of solid rivet strength) but require heavy equipment and more time. For most industrial, automotive, HVAC, and hardware applications—including the folding bed case above—semi‑tubular rivets provide more than enough strength while keeping production efficient. Choose solid rivets only for extreme structural loads where maximum shear strength is the only priority.

Q2: Can steel semi tubular rivets be used outdoors without rusting?

A: Yes, with the right finish. Uncoated steel will rust quickly when exposed to moisture. Our standard low‑carbon steel rivets are available with zinc plating (clear, blue, or yellow) which provides 48–96 hours of salt spray resistance—sufficient for indoor and sheltered outdoor use. For the folding bed case above, zinc plating provided 72 hours of protection against occasional damp conditions. For more demanding outdoor or coastal environments, we recommend switching to stainless steel semi‑tubular rivets (304 or 316) which offer 200–1,000+ hours of salt spray protection.

Q3: How do I select the correct barrel length for a steel semi tubular rivet?

A: Select a barrel length approximately 1.5–2.0mm longer than your total material stack thickness. For example, if you are joining two 2mm steel sheets (total 4mm), choose a barrel length of 5.5–6.0mm. This extra length provides enough material for the hollow section to roll outward and form a secure clinch without bottoming out. If the barrel is too short, the clinch will be weak. Too long, and the barrel may crumple. Rivet length is measured from the underside of the rivet head to the end of the body. Send us your material stack thickness, and we will recommend the exact barrel length.

Ready to Optimize Your Assembly Line?

If you are currently using solid rivets and dealing with slow assembly, deformed materials, or high tooling costs, switching to steel semi tubular rivets can make a significant difference.

What we offer you:

• Multiple head styles – Round, oval, truss, flat, and countersunk
• Wide shank range – 1.5mm to 8.0mm
• Custom lengths – Barrel length to your exact material stack
• Zinc plating as standard – 48–96 hours salt spray protection
• ISO 9001:2015 – Full quality system with traceable documentation

Get started in three steps:

• Send us your specs – Shank diameter, barrel length (or material stack thickness), head style, finish, and quantity
• We respond within 24 hours – With tooling cost (if any), piece price, and lead time
• We ship samples – 20–50 free pieces for you to test on your actual material

Send your inquiry to Nuote Metals today.