Torsion Testing Machine: Types, Specifications and How to Choose

Every shaft, bolt, spring and cable in a machine carries a twisting load at some point in its working life. A torsion testing machine puts a controlled twist on a sample and records how it responds: how much torque it takes to reach a given angle, where the material starts to yield, and at what point it finally fractures. That information feeds directly into design calculations, production quality checks and failure investigations.

Explore the wider metal testing machines we offer, including metal torsion testing.

If you are comparing torsion testing machines for the first time, this guide covers the main machine types, the specifications that actually matter, and the questions to ask before you buy.

What a Torsion Test Measures

A torsion test applies a twisting moment to a specimen while measuring the resulting angle of twist. From the torque–angle curve you can read the shear modulus, the torsional yield point and the ultimate shear strength of the material. For finished parts, torsion testing verifies that a component stays inside its design envelope — that a spring develops the right torque at the right deflection, or that a bolted joint tightens consistently.

Types of Torsion Testing Machines

Torsion testers fall into a few broad families. The right one depends on what you test and how often you test it.

Mechanical torsion testing machines

Simple machines with manual or motor-driven twisting and a dial or gauge readout. They are inexpensive and robust, but speed control is limited and results depend heavily on the operator. They suit occasional checks on small samples where high repeatability is not required.

Microcomputer-controlled electronic torsion testers

The workhorse of most laboratories. A servo drive twists the specimen, a torque sensor measures the reaction, and software plots the torque–angle curve and calculates shear modulus, yield strength and shear strength automatically. Typical series cover torque ranges from about 10 N·m up to 1000 N·m and above, often with several interchangeable sensors on one frame so that both small and large samples can be tested at good accuracy. The CJD-1000 torsion testing machine is an example of this class, while the TNS-W100P 100 N·m technical solution packages a compact microcomputer-controlled tester for smaller workloads. Our JWD-1000 microcomputer torsion tester measures torque from 10 N·m with a resolution of about 0.001 N·m and a 1 kW drive.

Torsional fatigue testers

For parts that see repeated twisting in service — shafts, couplings, torsion bars, springs — a torsional fatigue tester applies cyclic torque and counts cycles to failure. These machines combine a torsion drive with a fatigue control system, and they are used to validate components rather than raw materials.

Bolt and fastener torsion testers

Dedicated machines for torque coefficient, friction coefficient and clamp force testing of threaded fasteners, usually following ISO 16047. They measure the relationship between applied torque and the resulting axial clamp force, which is critical for controlled tightening in structural and automotive assembly.

Key Specifications to Compare

Spec sheets look similar at a glance, but a few numbers decide whether a machine will fit your work.

• Torque range. The usable range of the machine, or of the sensors that can be fitted to it. Choose a range that covers your samples with margin, and remember that accuracy is usually quoted against the rated capacity of the sensor — a 1000 N·m machine is the wrong tool for a 1 N·m sample.
• Torsional speed and angle control. How fast the machine can twist and how precisely it holds a target angle. Standard tests run at a constant rate of twist; some applications need angle-positioning or torque-hold modes.
• Measurement accuracy. Torsion-machine force/torque measurement is verified to ISO 7500-1 (ASTM E4 equivalent), with sensors commonly supplied as class 0.5 or class 1 (±0.5 % / ±1 %) and calibration certificates normally issued for 12 months. Ask for the accuracy statement in writing rather than taking the brochure at face value.
• Standards support. The machine and its software should implement the standards you work to — ISO 7800 (simple torsion of metallic wire), ISO 9649 (reverse torsion), GB/T 10128 for room-temperature torsion testing of metallic materials, ISO 16047 for fastener torque/clamp force testing, and the corresponding national standards for other materials.
• Software and data traceability. Look for torque–angle curves, automatic calculation of shear modulus and shear strength, and clean export to Excel, CSV or PDF. If customers or certification bodies ask for test records, you need reports that are easy to reproduce and audit.

Common Applications

• Metal materials — shafts, rods, wires and tubes: shear properties, torsional yield and fracture behaviour, as tested on machines like the 100 N·m computerized metal material torsion testing machine.
• Fasteners — torque coefficient, friction coefficient and clamp force, plus breakaway torque checks.
• Springs — torsion springs and torque–deflection verification.
• Cables and wire ropes — twist behaviour and quality control of stranded products.
• Plastics and composites — torsional stiffness and shear response where a brittle tension test does not reflect real service loading.

How to Choose a Torsion Testing Machine

• Start with the specimen. Material, size and the parameter you actually need — shear strength, torque coefficient, fatigue life — determine the machine family.
• Size the torque with margin. The maximum torque you expect, plus a working margin of roughly 20–30%, sets the machine capacity. Multiple sensor ranges extend usable accuracy across different sample sizes.
• Match the standard. If you quote tests to ISO 16047 or GB/T 10128, make sure the machine and software implement those methods, including the report formats they define. Test results are only comparable when quoted with the standard, the specimen geometry, the test speed and the force-measurement class.
• Check the extras. Grips and fixtures for your sample geometry, a temperature chamber if you need one, and software your operators will actually use. A machine that is awkward to run tends to get used less than it should.
• Ask about lead time and support. A testing machine is a long-term purchase. Calibration service, spare parts and response time matter as much as the initial price.

Still unsure which configuration fits your samples? Send your test requirements to annie@chenjitester.com or call +86 158 5311 1612 — we usually reply within 24 hours with a recommendation and a quotation. You can also browse the torsion testing machine series, look through the full product range, or reach us through the contact page.

Free tool: not sure what capacity you need? Use our UTM capacity selector — enter specimen size and material to get the recommended machine.

Frequently Asked Questions

Which standards do your torsion testing machines support?

ISO 7800 (simple torsion of metallic wire), ISO 9649 (reverse torsion), GB/T 10128 (room-temperature torsion of metallic materials) and ISO 16047 (fastener torque/clamp force testing).

How do I choose the right torque range?

Start from the maximum torque your samples will see and choose a machine that covers it with a comfortable working margin; interchangeable sensors let one frame cover both small and large samples with good accuracy.

What torque resolution can I expect?

On a microcomputer-controlled unit such as the JWD-1000, torque is measured from 10 N·m with a resolution of about 0.001 N·m and a 1 kW drive.

Can your machines test fasteners and bolts, not just raw material?

Yes — dedicated fastener torsion testers measure tightening torque and clamp (axial) force per ISO 16047 for bolt–nut combinations.

Do you offer torsional fatigue testing?

Yes. For parts under repeated twisting in service (shafts, couplings, torsion bars, springs), a torsional fatigue tester applies cyclic torque and counts cycles to failure.

What about calibration and data traceability?

Measurement follows ISO 7500-1 / ASTM E4, sensors are typically class 0.5 or class 1, calibration certificates are normally issued for 12 months, and the software plots the torque–angle curve and exports to Excel, CSV or PDF.

What is the MOQ and lead time?

Machines are built to order — MOQ is one unit, and lead time depends on the configuration. Send your specimen and standard, and we usually reply within 24 hours with a recommendation and quotation.

Do you export, and what certifications do you hold?

CHENJI is ISO 9001 certified (626024QH073R1), has manufactured since 2014, and has served 1,000+ customers in 27 countries.