In a nutshell: Contract measurement is an external measurement service in which a specialized service provider performs dimensional inspections of components and workpieces on behalf of the customer and documents the measurement results in a traceable report. Typical methods include tactile coordinate measurement, optical scanning, and industrial computed tomography (CT).
Companies that do not have their own in-house measurement technology or whose capacities are reaching their limits often face the question: How can components be inspected reliably and with full traceability? This is exactly where our 3D contract measurement service comes in. We handle the dimensional measurement of your components on your behalf from quick dimensional checks of individual parts to complete initial sampling of complex assemblies and provide you with reliable, documented measurement results for your quality assurance. Instead of investing in expensive equipment yourself, you can rely on our facilities, our expertise, and in particular industrial computed tomography, which allows even complex geometries to be measured non-destructively.
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What is a wage survey, and when is it worthwhile?
Contract measurement is an external measurement service in which a specialized service provider performs dimensional inspections of your components. Instead of setting up their own measurement laboratory, companies send their workpieces to a partner who has the necessary equipment, expertise, and appropriate measurement methods. The scope ranges from the simple measurement of a single part to the complete initial sampling of entire assemblies from the receipt of the parts through the measurement process to the final, documented report.
Contract measurement is particularly useful when measurement tasks are complex, in-house measurement equipment is at full capacity, or a short-term bottleneck needs to be bridged. Many companies also use contract measurement as an external, documented second opinion, for example, in the case of complaints or disputed tolerances. Precise contract measurement thus provides certainty without disrupting ongoing production.
Small and medium-sized enterprises, in particular, benefit from receiving high-quality measurement results without having to maintain a permanent staff or expensive equipment. Outsourced measurement therefore means not only purchasing capacity but also gaining access to expert knowledge and established testing processes documented in accordance with recognized standards.
What measurement technology is used in 3D contract measurement?
Modern measurement technology is at the heart of every professional measurement service. Depending on the requirements, different systems are used: tactile coordinate measuring machines for high-precision individual measurements, optical scanners for the rapid capture of large surfaces, and industrial computed tomography for viewing the interior of enclosed components. The choice of measuring device depends on the material, geometry, and inspection objective.
For simple, easily accessible measurements, a tactile method in which a probe scans the surface point by point is often sufficient. However, as soon as free-form surfaces, thin-walled plastic parts, or internal structures come into play, optical and tomographic measurement methods demonstrate their strengths. An experienced service provider selects the most reliable method for each specific application, rather than attempting to solve every task with a single device.
The range of measurement tasks is broad: it extends from the rapid verification of a single dimension to the complete capture of a geometry and the inspection of safety-critical components. A good partner will therefore advise you in advance on which approach reliably meets the required measurement uncertainty and which measurement data you actually need for subsequent processing.
How does industrial computed tomography work in contract measurement?
Industrial computed tomography (CT) uses X-rays to scan a component from multiple angles and, depending on the material, wall thickness, resolution, and measurement strategy, reconstructs a three-dimensional volume dataset that can reveal both internal and external structures. Unlike tactile or optical methods, CT can thus also detect undercuts, cavities, and assembled components without disassembling or destroying the part. In the context of dimensional metrology, this does not refer to just any CT, but rather to CT used as a sensing technology in coordinate measuring machines. Of particular relevance here are the DIN EN ISO 10360 series of standards and the application guidelines with identical content VDI/VDE 2617 Part 13 and VDI/VDE 2630 Part 1.3 for CMMs with CT sensors. Part 11, which is specifically tailored to CT, is currently available only as a draft (ISO/DIS 10360-11 or DIN EN ISO 10360-11:2021-04) and should not be cited as a valid final standard.
Essentially, the measurement process consists of three steps: volume acquisition, surface reconstruction, and evaluation against the target values. The software automatically evaluates radii, chamfers, bores, and complex contours and generates traceable reports. This creates a precise digital representation of a physical workpiece that can be used for further analysis, such as wall thickness analyses or porosity assessment of castings.
At Microvista, this process is designed for throughput and reproducibility: Once a part’s volume data set has been captured, numerous features, cross-sections, and target-actual comparisons can be analyzed retrospectively without having to measure the part again, all within the limits of resolution, material, radiopacity, and measurement strategy.
How are complex geometries and free-form surfaces measured?
Complex geometries pose the greatest challenge in metrology. Enclosures with undercuts, additively manufactured structures, or organically shaped design components can hardly be fully captured using individual point measurements. This is where surface- and volume-based 3D measurement methods come into play, combining millions of points into a complete model.
Free-form surfaces are measured optically or via computed tomography and then aligned with the CAD model. The result is a color-coded target-actual comparison that displays every deviation across the entire surface. This allows designers to see at a glance where a component deviates from specifications and whether the manufacturing process needs to be readjusted.
For nested assemblies or components with internal structures, industrial CT provides results that would be impossible to achieve with traditional methods. Component geometries that previously required destructive testing such as sawing and cross-sectional analysis can now be analyzed completely and non-destructively. The component generally remains mechanically intact and, depending on the application, can be reused after contract measurement.
What happens during the analysis and CAD comparison?
Simply collecting data is only the first step. The true value of a dimensional inspection lies in the analysis and comparison with the CAD data. In this process, the measured points are superimposed on the digital design template, so that any deviation ranging from micrometers to millimeters (mm) is visible and documented.
CAD comparisons not only show whether a dimension is within tolerance, but also in which direction and to what extent deviations occur. This detailed representation helps identify systematic errors in manufacturing early on and take targeted corrective action. In addition, reports for initial sampling or ongoing quality control can be generated from the measurement data.
Another application is reverse engineering: If no model is available, the scan data can be used to derive a dimensionally accurate, processable CAD model, the accuracy of which depends on resolution, data quality, and surface reconstruction. Especially for older components without digital documentation, this is often the only way to reproduce a replacement part with dimensional accuracy.
What role does wage measurement play in quality assurance?
In quality assurance, contract measurement is a key component for verifying dimensional accuracy throughout the entire value chain. Whether during incoming inspection, initial sampling, or the release of production runs, documented measurement results form the basis for decision-making and for communication with customers and suppliers.
Many industries today require traceably documented inspections conducted in accordance with recognized rules, such as relevant standards and guidelines like VDI/VDE 2630. A service provider with a quality management system certified to DIN EN ISO 9001 demonstrates defined and regularly audited processes. Furthermore, the reliability of individual results stems from measurements conducted in accordance with standards and a traceably documented report that can withstand a customer audit.
Precisely because an external partner performs the testing and documents the results, the measurement results gain additional credibility. An external, documented test report often resolves disputes between suppliers and customers more quickly, as both parties can rely on the same documented values.
How does wage measurement support mass production and high-volume production?
Not every measurement task involves a single prototype part. As soon as a larger number of parts needs to be inspected, internal capacities quickly reach their limits. Mass-production measurements tie up personnel and machines for days on end and can thus become a bottleneck in day-to-day operations.
This is where external measurement services excel in terms of scalability. Specialized service providers have multiple systems and well-established, partially automated processes that allow even large volumes to be handled with short turnaround times. CT, in particular, is well-suited for series testing because once a test program is created, it can be applied to every subsequent part—even across large batches—using the same test strategy and reproducible evaluation conditions.
Outsourcing such measurements frees up in-house resources for core tasks. This shortens turnaround times in-house and makes planning more predictable, as inspection capacity can be flexibly procured.
What equipment and testing instruments are needed to ensure reliable results?
Reliable measurement results require more than just a single measuring instrument. What is needed is a coordinated set of equipment comprising coordinate measuring machines, optical systems, and high-performance CT systems for a variety of component sizes and materials—from delicate plastic parts to dense metal components. Only this combination can cover the entire spectrum of measurement tasks.
An expert knows how to perform a measurement procedure for a specific material and which approach yields the best results. This metrological expertise distinguishes a high-performance service provider from a mere machine operator.
As a service provider specializing in industrial computed tomography, we at Microvista operate several CT systems across different performance classes and assess, even before a project is commissioned, whether a component is suitable for the process. For many customers, this preliminary feasibility assessment is the most important consideration of all—even more so than price.
When does it make more sense to rent measurement equipment rather than use your own?
The decision between in-house measurement technology and external contract measurement depends on the volume, variety, and complexity of the inspection tasks. For those who inspect similar parts on a daily basis, an in-house system is often more cost-effective. However, as soon as the tasks vary, occur infrequently, or become particularly demanding, the cost-benefit analysis shifts in favor of contract measurement.
An in-house measurement lab incurs high fixed costs for equipment, maintenance, software, and personnel. Outsourced measurement, on the other hand, is a variable cost that is incurred only when measurements are actually taken. For complex geometries that require specialized methods such as CT, access to external specialized equipment is usually the more economical and faster solution, especially since CT systems are among the most expensive investments in dimensional metrology.
Request a Quote for Your 3D Contract Measurement
Do you have a component that needs to be measured, but aren’t sure if industrial computed tomography is the right method? Send us your request, including the material, approximate dimensions, and testing objective. We’ll assess the feasibility, recommend the appropriate measurement method, and provide you with the turnaround time and terms all with no obligation and in a transparent manner. This way, you’ll know what measurement results to expect before placing an order.
Frequently Asked Questions About 3D Contract Measurement
Generally, components made of plastic, metals, and many other materials, ranging from a few millimeters to medium-sized assemblies. How well a part can be imaged depends primarily on the material and wall thickness. That is why we assess feasibility before every order and let you know whether computed tomography is likely to be the appropriate method for your measurement task.
The price depends on the procedure, component size, quantity, and scope of the analysis. A single CT scan with standard analysis is priced differently than a documented initial sampling or a production run measurement. Send us your request, and you’ll receive a transparent, no-obligation quote.
No, generally not. Industrial computed tomography is a non-destructive process: The part is scanned with radiation—it is not disassembled or cut open—and remains mechanically unchanged afterward, unlike with traditional cross-sectional images. For radiation-sensitive materials, electronics, or specific material combinations, we assess suitability in advance.
That depends on the complexity and quantity. Individual parts can often be measured on very short notice, while documented series measurements may require a bit more lead time. We’ll provide you with a binding lead time in our quote, especially if you need to bridge a bottleneck.
To perform a target-actual comparison, we need your CAD data as well as the dimensions and tolerances to be checked. If no model is available, we can also perform a simple measurement or use reverse engineering, in which we derive a new CAD model from the scan data.
You will receive a clearly documented measurement report via our secure InspectHub portal.
Sources and Related Standards
DIN EN ISO 10360-1: Terms Used in Acceptance and Verification Testing for Coordinate Measuring Machines
DIN EN ISO 10360-2: Acceptance and Verification Testing for CMMs in Length Measurements
DIN EN ISO 10360-7: CMMs with image processing systems, for distinguishing between optical sensors
VDI/VDE 2630 Blatt 1.1: Fundamentals and Terminology of CT in Dimensional Measurement Technology
VDI/VDE 2630 Blatt 1.2: Factors Affecting CT Measurement Results and Recommendations
VDI/VDE 2617 Blatt 13 / VDI/VDE 2630 Blatt 1.3: Application Guide to DIN EN ISO 10360 for CMMs with CT Sensors
VDI/VDE 2630 Blatt 1.4: Classification and Comparison of Various Dimensional Measurement Methods
VDI/VDE 2630 Blatt 2.1: Determination of Task-Specific Measurement Uncertainty and Test Process Suitability of CMMs with CT Sensors
DIN EN ISO 15530-3: Determination of Measurement Uncertainty Using Calibrated Workpieces or Standards
DIN EN ISO 14253-1: Decision Rules for Conformity and Nonconformity, Taking Measurement Uncertainty into Account
DIN EN ISO 9001: Requirements for Quality Management Systems