--- title: "What Are Tube-End Threaded Inserts Used For?" description: "Tube-End Threaded Inserts (Trade series (pressed tube-end inserts)) are used for adding a retained internal thread to a round or square tube through a presse…" url: https://engineeringhardware.com/applications/tube-end-threaded-inserts/ source: Engineering Hardware & Fasteners --- # What Are Tube-End Threaded Inserts Used For? Threaded Inserts · Trade series (pressed tube-end inserts) · Application guide Typical applications, the industries that specify tube-end threaded inserts, and how to choose the right size, material and finish for the joint. Tube-End Threaded Inserts are used for adding a retained internal thread to a round or square tube through a pressed crown or flange. They are manufactured to Trade series (pressed tube-end inserts), and selection is driven by the nominal diameter, the fit and tolerance the assembly requires, and the service environment. - **Primary duty:** Adding a retained internal thread to a round or square tube through a pressed crown or flange - **Governing standard:** Trade series (pressed tube-end inserts) - **Category:** Threaded Inserts Application notes are general engineering guidance. Verify the property class and any approval requirement against your own design calculation. ![What Are Tube-End Threaded Inserts Used For? application image](https://engineeringhardware.com/wp-content/uploads/2026/09/Tube-Connecting-Nuts-Tube-End-Threaded-Inserts.webp) Tube-End Threaded Inserts (Trade series (pressed tube-end inserts)) are specified where the joint requires adding a retained internal thread to a round or square tube through a pressed crown or flange. The sections below cover the typical end-uses by industry, the size and material decisions for each, assembly practice, and the applications this fastener type is not suited to. ## Typical Applications for Tube-End Threaded Inserts The most common settings where these are specified: - **Tubular furniture:** Pressed end inserts add a threaded point without welding a nut inside the tube. - **Display frames:** Round and square tube versions support removable brackets. - **Light machinery:** Crown retention holds a stud or screw connection at the tube end. - **Fabricated enclosures:** Zinc-plated steel provides a practical general-purpose insert. Product catalog ## Related Tube-End Threaded Inserts products [![M3 M4 M5 M6 304 Stainless Steel Waterproof Sealed Close End Knurled Round Body Flat Head Blind Rivet Nut](https://img.engineeringhardware.com/M3-M4-M5-M6-304-Stainless-Steel-Waterproof-Sealed-Close-End-Knurled-Round-Body-Flat-Head-Blind-Rivet-Nut.webp)](https://engineeringhardware.com/product/m3-m4-m5-m6-304-stainless-steel-waterproof-sealed-close-end-knurled-round-body-flat/) Rivet Nuts & Threaded Rivet Inserts ### [M3 M4 M5 M6 304 Stainless Steel Waterproof Sealed Close End Knurled Round Body Flat Head Blind Rivet Nut](https://engineeringhardware.com/product/m3-m4-m5-m6-304-stainless-steel-waterproof-sealed-close-end-knurled-round-body-flat/) Hexagon Head · DIN, ANSI, GB, JIS, GOST, BSW **US$0.012 – 6.79**MOQ 100 pieces [![Type B Closed Sealed End Blind Nut Self Clinching Waterproof Blind Press Nut](https://img.engineeringhardware.com/Type-B-Closed-Sealed-End-Blind-Nut-Self-Clinching-Waterproof-Blind-Press-Nut.webp)](https://engineeringhardware.com/product/type-b-closed-sealed-end-blind-nut-self-clinching-waterproof-blind-press-nut/) Rivet Nuts & Threaded Rivet Inserts ### [Type B Closed Sealed End Blind Nut Self Clinching Waterproof Blind Press Nut](https://engineeringhardware.com/product/type-b-closed-sealed-end-blind-nut-self-clinching-waterproof-blind-press-nut/) Round Head · DIN, ANSI, GB, JIS, GOST, BSW **US$0.012 – 0.12**MOQ 1 piece [![M5 Rivet Nut Aluminum Alloy Knurled Flat Head Thread Embedded Nut (silver)](https://img.engineeringhardware.com/M5-Rivet-Nut-Aluminum-Alloy-Knurled-Flat-Head-Thread-Embedded-Nut-silver.webp)](https://engineeringhardware.com/product/m5-rivet-nut-aluminum-alloy-knurled-flat-head-thread-embedded-nut-silver/) Rivet Nuts & Threaded Rivet Inserts ### [M5 Rivet Nut Aluminum Alloy Knurled Flat Head Thread Embedded Nut (silver)](https://engineeringhardware.com/product/m5-rivet-nut-aluminum-alloy-knurled-flat-head-thread-embedded-nut-silver/) Insert Nut · DIN, ANSI, GB, JIS, GOST, BSW **US$0.0096 – 0.012**MOQ 1 piece [![Stainless Steel Hex Socket Flat Head Furniture Bolts & Splint Barrel Sleeve Connector Nuts](https://img.engineeringhardware.com/Stainless-Steel-Hex-Socket-Flat-Head-Furniture-Bolts-Splint-Barrel-Sleeve-Connector-Nuts.webp)](https://engineeringhardware.com/product/stainless-steel-hex-socket-flat-head-furniture-bolts-splint-barrel-sleeve-connector/) Rivet Nuts & Threaded Rivet Inserts ### [Stainless Steel Hex Socket Flat Head Furniture Bolts & Splint Barrel Sleeve Connector Nuts](https://engineeringhardware.com/product/stainless-steel-hex-socket-flat-head-furniture-bolts-splint-barrel-sleeve-connector/) Hex Socket Barrel Rivet Nut · DIN, ANSI, GB, JIS, GOST, BSW, ISO **US$0.012 – 0.12**MOQ 10,000 pieces [![Factory Direct Zinc Plated Self Clinching Insert Nut Sheet Metal Rivet Nut for Auto Parts](https://img.engineeringhardware.com/Factory-Direct-Zinc-Plated-Self-Clinching-Insert-Nut-Sheet-Metal-Rivet-Nut-for-Auto-Parts.webp)](https://engineeringhardware.com/product/factory-direct-zinc-plated-self-clinching-insert-nut-sheet-metal-rivet-nut-for-auto/) Rivet Nuts & Threaded Rivet Inserts ### [Factory Direct Zinc Plated Self Clinching Insert Nut Sheet Metal Rivet Nut for Auto Parts](https://engineeringhardware.com/product/factory-direct-zinc-plated-self-clinching-insert-nut-sheet-metal-rivet-nut-for-auto/) Auto Fasteners · DIN, GB, ISO, ANSI/ASTM, BS, Bsw, JIS etc. **US$0.012 – 0.024**MOQ 20,000 pieces [![Factory Price Sanitary Stainless Steel 304/316L Blind Nut Blank Nut](https://img.engineeringhardware.com/Factory-Price-Sanitary-Stainless-Steel-304-316L-Blind-Nut-Blank-Nut.webp)](https://engineeringhardware.com/product/factory-price-sanitary-stainless-steel-304-316l-blind-nut-blank-nut/) Rivet Nuts & Threaded Rivet Inserts ### [Factory Price Sanitary Stainless Steel 304/316L Blind Nut Blank Nut](https://engineeringhardware.com/product/factory-price-sanitary-stainless-steel-304-316l-blind-nut-blank-nut/) Round Head · DIN **US$0.60 – 9.60**MOQ 1 piece [View all Rivet Nuts & Threaded Rivet Inserts →](https://engineeringhardware.com/fastener-products/threaded-inserts-clinch-fasteners/rivet-nuts-threaded-rivet-inserts/) [Full product catalog](https://engineeringhardware.com/products/) ## How to Specify Tube-End Threaded Inserts for Your Application - **Size:** Match the size to the mating part — see the dimension table below for each option. - **Tap & length:** Drill and tap to the specified STI size, and pick insert length (commonly 1.5×D or 2×D) for the load and parent material strength. - **Environment:** For damp, coastal or chemical exposure prefer A4/316 stainless or a suitable coating; indoors, plated steel or A2 is usually sufficient. - **Standard:** This product is supplied to Trade series (pressed tube-end inserts). Quoting the standard on your order guarantees interchangeable dimensions between suppliers. ## Installation & Assembly Practice - Drill and tap with the specified STI tap — a standard tap will not produce the correct thread for the insert. - Install to the specified depth (typically 0.25–0.5 mm below the surface) and remove the tang where the design requires it. ## Common Selection Mistakes with Tube-End Threaded Inserts - Fitting an insert into strong steel that already holds a thread — added cost for no gain. - Skipping the tang removal, which then blocks the mating screw. ## Where Tube-End Threaded Inserts Are Not the Right Choice Not a fix for a hole that is already oversized beyond the STI tap range, and not needed in steel that already holds a thread well. Custom manufacturing · Made to drawing ## Need a tube-end threaded inserts outside the standard range? Thread size, body length, knurl or key form and installation method are all variable against the parent material. Made by tapping or knurling. Minimum order from 2,000 pieces; samples within 7 days of drawing approval. [Custom threaded insert manufacturing](https://engineeringhardware.com/custom/inserts/)[Send a drawing](https://engineeringhardware.com/custom/inserts/#rfq) ## Technical Drawing Dimensioned line drawing of round tube Tube-End Threaded Inserts to Trade series (pressed tube-end inserts). Side view and top view, drawn to the dimensions in the table below and redrawn for any size selected. - **Thread size:** M8 - **Tube dimension / inside diameter (mm):** inside diameter 20.5 - **Insert code example:** ITT2T/M8/19.5 - **Retention:** pressed crown / flange - **Material options:** steel / zinc-plated steel ## Dimensions & Specifications (Trade series (pressed tube-end inserts)) | Tube form | Thread size | Tube dimension / inside diameter (mm) | Insert code example | Retention | Material options | | --- | --- | --- | --- | --- | --- | | round tube | M8 | inside diameter 20.5 | ITT2T/M8/19.5 | pressed crown / flange | steel / zinc-plated steel | | square tube | M6 | 20×20 | ITQ2S/M6/18.9 | pressed crown / flange | steel / zinc-plated steel | Inside the plant ## Manufactured in our own plant This part is cold-formed, threaded, heat-treated and finished in-house. The stages below are where its class and finish are actually decided. 1. ![Wire rod feeding into a cold heading machine](https://engineeringhardware.com/wp-content/uploads/2026/08/09-wire-rod-feed-cold-heading-machine.webp) 01 **Cold heading** Wire rod is drawn to size and cold-formed into blanks. Forming rather than cutting keeps the grain flow continuous around the head, which is where a bolt is most likely to fail. Head dimensions and under-head radius checked at set-up and per shift. 2. ![Thread rolling machine producing bolt threads](https://engineeringhardware.com/wp-content/uploads/2026/08/03-thread-rolling-machine-bolt-production.webp) 02 **Thread rolling** Threads are rolled between hardened dies rather than cut. Rolled threads are stronger in fatigue than cut threads and hold pitch and flank angle far more consistently across a batch. Go / no-go ring gauges to ISO 965 tolerance class 6g. 3. ![Baskets of bolts staged for heat treatment](https://engineeringhardware.com/wp-content/uploads/2026/08/05-heat-treatment-baskets-black-bolts.webp) 03 **Heat treatment** Quench-and-temper brings carbon and alloy steel to the property class ordered — 8.8, 10.9 or 12.9 — with the furnace charge tracked so a finished lot can be traced back to it. Core hardness and tensile tested per lot to ISO 898-1. 4. ![Zinc plated bolts in a treatment basket](https://engineeringhardware.com/wp-content/uploads/2026/08/23-zinc-plated-bolts-treatment-basket.webp) 04 **Surface treatment** Zinc, zinc-nickel, hot-dip galvanizing, black oxide, phosphate and Dacromet, selected against the service environment rather than against the price list. Coating thickness and neutral salt spray hours to ISO 9227. ## Frequently Asked Questions ### What material should Tube-End Threaded Inserts be for outdoor use? For damp, coastal or chemical environments specify A4 (316) stainless or a suitably coated steel. For indoor or dry use, A2 (304) stainless or zinc-plated steel is normally adequate. ### Are Tube-End Threaded Inserts made to a recognized standard? Yes — they are manufactured to Trade series (pressed tube-end inserts), so dimensions are interchangeable between suppliers when you quote the standard on your order. ### What are Tube-End Threaded Inserts used for? Adding a retained internal thread to a round or square tube through a pressed crown or flange. They are supplied to Trade series (pressed tube-end inserts). ### Which industries use Tube-End Threaded Inserts? They are commonly specified in tubular furniture, display frames and light machinery, among other sectors. ### Can I get a quote for Tube-End Threaded Inserts in the size and material I need? Yes. Use the technical drawing and quote form on this page to set the size and options, then send the exact configuration to our team for pricing and lead time. ## Related Pages Product page: [Tube-End Threaded Inserts — specifications & sizes](https://engineeringhardware.com/fastener/tube-end-threaded-inserts/) ### Tube-End Threaded Inserts Specification Guides ### Related Fastener Applications