--- title: "What Are Equal-End Stud Bolt Used For?" description: "Equal-End Stud Bolts (GB/T 901 / DIN 939) are used for clamping a joint from both ends where a headed bolt cannot be used, tightened by the nuts rather than…" url: https://engineeringhardware.com/applications/cad-svg-093-stud/ source: Engineering Hardware & Fasteners --- # What Are Equal-End Stud Bolt Used For? Bolts · GB/T 901 / DIN 939 · Application guide Typical applications, the industries that specify equal-end stud bolt, and how to choose the right size, material and finish for the joint. Equal-End Stud Bolts are used for clamping a joint from both ends where a headed bolt cannot be used, tightened by the nuts rather than by the fastener itself. They are manufactured to GB/T 901 / DIN 939, and the choice of size, property class and finish is driven by the load in the joint and the environment it sits in. - **Primary duty:** Clamping a joint from both ends where a headed bolt cannot be used, tightened by the nuts rather than by the fastener itself - **Governing standard:** GB/T 901 / DIN 939 - **Thread size range:** M6 to M36 - **Category:** Bolts Application notes are general engineering guidance. Verify the property class and any approval requirement against your own design calculation. ![What Are Equal-End Stud Bolt Used For? application image](https://engineeringhardware.com/wp-content/uploads/2026/06/Equal-End-Stud-Bolt-—-GB-T-901-DIN-939-Series-093-—-GB-T-901-DIN-939.webp) The primary duty of Equal-End Stud Bolts is clamping a joint from both ends where a headed bolt cannot be used, tightened by the nuts rather than by the fastener itself. Below: the sectors that specify them in volume, the checklist used to select the right size and material for the application, installation notes, and the known limits of the type. Stocked across roughly M6 to M36, they cover general to heavy-duty work. ## Typical Applications for Equal-End Stud Bolt — GB/T 901 / DIN 939 (Series 093) The most common settings where these are specified: - **Automotive & transport:** chassis, suspension and powertrain mounting points subject to vibration. - **Heavy machinery:** securing gearboxes, frames and guarding on plant that sees shock loads. - **Energy & infrastructure:** tower, pylon and pipework supports exposed to weather and long service life. - **General machine building:** fastening covers, brackets, motors and sub-assemblies on production equipment. - **Maintenance & repair (MRO):** a stocked size for servicing existing plant where the original fastener spec must be matched. ## How to Specify Equal-End Stud Bolt — GB/T 901 / DIN 939 (Series 093) for Your Application - **Size:** Match the nominal size to the mating thread or hole. This product spans M6–M36; check the full table below for the exact dimensions of each size. - **Strength class:** Choose the property class (e.g. 8.8, 10.9, 12.9 or A2/A4 stainless) for the load and environment, and tighten to the matching torque so the joint relies on preload, not friction. - **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 GB/T 901 / DIN 939. Quoting the standard on your order guarantees interchangeable dimensions between suppliers. ## Installation & Assembly Practice - Tighten to the torque for the size and property class with a calibrated wrench — the joint is held by preload, not by the thread friction alone. - Ensure at least one full thread projects beyond the nut after tightening, and never re-use a bolt that has been tightened into yield. - Under slotted or oversized holes, fit a hardened washer so the preload does not relax into the hole edge. ## Common Selection Mistakes with Equal-End Stud Bolt — GB/T 901 / DIN 939 (Series 093) - Specifying class 12.9 "to be safe" in a corrosive environment — high classes are more sensitive to hydrogen embrittlement and stress corrosion; 8.8 hot-dip galvanized often outlasts them outdoors. - Choosing a length that puts the shear plane through the threaded portion when a plain shank (partially threaded bolt) was available. - Mixing stainless bolts with plated-steel nuts: the joint loses its corrosion logic and can gall or seize. ## Where Equal-End Stud Bolt — GB/T 901 / DIN 939 (Series 093) Are Not the Right Choice Not for permanent joints that will never be opened (a rivet or weld is cheaper), and not where the head must sit flush — use a countersunk screw instead. Custom manufacturing · Made to drawing ## Need a equal-end stud bolt outside the standard range? Dimensions, material, finish and form are specified from the drawing — a bolt outside the standard range is a variation on existing tooling rather than a new design. Made by cold heading or hot forging. Minimum order from 2,000 pieces; samples within 7 days of drawing approval. [Custom bolt manufacturing](https://engineeringhardware.com/custom/bolts/)[Send a drawing](https://engineeringhardware.com/custom/bolts/#rfq) ## Technical Drawing Dimensioned line drawing of M6 Equal-End Stud Bolt — GB/T 901 / DIN 939 (Series 093) to GB/T 901 / DIN 939. Side view and top view, drawn to the dimensions in the table below and redrawn for any size selected. - **Pitch (mm):** 1.0 - **Length L (mm):** 50 - **Engagement depth bm (mm):** 8 - **Material:** Cl. 8.8 alloy steel ## Dimensions & Specifications (GB/T 901 / DIN 939) | Thread size | Pitch (mm) | Length L (mm) | Engagement depth bm (mm) | Material | Reference standard | | --- | --- | --- | --- | --- | --- | | M6 | 1.0 | 50 | 8 | Cl. 8.8 alloy steel | DIN 939 / GB/T 901 | | M8 | 1.25 | 60 | 10 | Cl. 8.8 alloy steel | DIN 939 / GB/T 901 | | M10 | 1.5 | 80 | 15 | Cl. 8.8 alloy steel | DIN 939 / GB/T 901 | | M12 | 1.75 | 100 | 18 | Cl. 8.8 alloy steel | DIN 939 / GB/T 901 | | M14 | 2.0 | 120 | 21 | Cl. 8.8 alloy steel | DIN 939 / GB/T 901 | | M16 | 2.0 | 150 | 24 | Cl. 8.8 alloy steel | DIN 939 / GB/T 901 | | M20 | 2.5 | 180 | 30 | Cl. 8.8 alloy steel | DIN 939 / GB/T 901 | | M24 | 3.0 | 200 | 36 | Cl. 8.8 alloy steel | DIN 939 / GB/T 901 | | M30 | 3.5 | 240 | 45 | Cl. 8.8 alloy steel | DIN 939 / GB/T 901 | | M36 | 4.0 | 280 | 54 | Cl. 8.8 alloy steel | DIN 939 / GB/T 901 | 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 ### How tight should Equal-End Stud Bolt — GB/T 901 / DIN 939 (Series 093) be torqued? Tighten to the torque for the size and property class so the joint is held by bolt preload. The size pages and torque reference table give recommended values; use a calibrated torque wrench for anything structural. ### What material should Equal-End Stud Bolt — GB/T 901 / DIN 939 (Series 093) 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 Equal-End Stud Bolt — GB/T 901 / DIN 939 (Series 093) made to a recognized standard? Yes — they are manufactured to GB/T 901 / DIN 939, so dimensions are interchangeable between suppliers when you quote the standard on your order. ### What are Equal-End Stud Bolt — GB/T 901 / DIN 939 (Series 093) used for? Clamping a joint from both ends where a headed bolt cannot be used, tightened by the nuts rather than by the fastener itself. They are supplied to GB/T 901 / DIN 939. ### Can I get a quote for Equal-End Stud Bolt — GB/T 901 / DIN 939 (Series 093) 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: [Equal-End Stud Bolt — GB/T 901 / DIN 939 (Series 093) — specifications & sizes](https://engineeringhardware.com/fastener/cad-svg-093-stud/) ### Equal-End Stud Bolt — GB/T 901 / DIN 939 (Series 093) Specification Guides ### Related Fastener Applications