Real-Time Release Testing in medical injection molding

RTRT is a quality assurance approach in which product quality is determined within the manufacturing process rather than through physical sample inspection. For medical plastic injection molding, RTRT enables in-process quality assurance of every part produced and the creation of auditable per-part quality evidence to support immediate release decisions.

Statistical Process Control (SPC) uses physical measurements from a defined and limited sample of manufactured parts to statistically assess the quality of a larger production batch. RTRT goes beyond this by assessing every part during production, using validated in-process quality data. This reduces statistical blind spots and can progressively reduce reliance on SPC, increasing release confidence while reducing quality-control bottlenecks, effort, and costs.

Kistler supports OEMs and CMOs in transitioning from SPC to RTRT.

Cavity pressure is measured directly inside the mold, where the part is formed, making it the most accurate quality-relevant signal in plastic injection molding. It captures how the main process conditions affect the part itself and is closely linked to its final quality. Once this relationship has been established and validated for the specific application, cavity pressure provides the foundation for reliable in-process quality determination.

Not automatically. Initially, the relationship between the cavity pressure signal and the relevant, specific quality characteristics of the part needs to be established and validated. Depending on the application, defined process limits or a specific quality model can then be used to determine whether the manufactured part meets the established acceptance criteria.

Kistler combines measurement technology with application expertise to help you establish, understand, and validate this relationship for your specific medical plastic injection molding application.

The Kistler MedRelease Suite is a complete suite of technologies and services for implementing RTRT in medical plastic injection molding. It combines high-precision cavity pressure measurement, real-time process monitoring and quality determination, data management and analysis with application expertise, training, and implementation support.

Together, these elements provide OEMs and CMOs with a structured path toward RTRT and auditable per-part release confidence.

No. The transition to RTRT is deliberately step by step. You begin by establishing reliable cavity pressure measurement and process monitoring, then build process understanding, introduce quality determination and data management, qualify the measurement equipment, validate the approach, and progressively move toward RTRT.

This allows confidence and internal expertise to grow alongside the technology. Kistler accompanies OEMs and CMOs throughout this journey, from establishing the measurement foundation and on to validation, implementation, and scaling.

No. In practice, existing physical measurements initially run alongside the new in-process approach. Comparing the results over time helps demonstrate that the quality determination is reliable and builds confidence among production and quality teams.

Once consistent results and a validated foundation have been established, physical measurement effort can be progressively reduced in line with your approved quality and release process.

The transition should be evidence-based and gradual. Physical measurements can initially continue alongside in-process quality determination, allowing results to be compared directly with established measurement methods over a meaningful amount of production data.

This parallel approach helps demonstrate equivalence and consistency, validate the measurement and quality-determination system, and build confidence within the quality teams. Once the required evidence has been established, physical measurement intervals can be reduced progressively in accordance with your approved quality and release process.

A quality model relies on its relationship with the defined physical part-quality characteristics and must be established and validated for each application. This includes comparing the quality model’s results with physical measurements and demonstrating that the model performs reliably within its defined operating range.

Kistler supports you in establishing and validating the quality model, assessing its accuracy and validity, and building the documented evidence needed to use it with confidence in production.

Implementation typically starts by establishing a reliable measurement foundation: selecting and positioning sensors, integrating them into the mold, installing and commissioning the monitoring system, and verifying correct signal acquisition.

The process and relevant quality characteristics are then investigated, acceptance criteria or quality models are established and validated, and the resulting approach is integrated into the customer’s quality and release process. During this, it is crucial to qualify the complete system as a measuring chain. From there, the validated approach can be transferred into series production and replicated across additional products, machines, lines, and locations.

Kistler supports OEMs and CMOs throughout this journey, from initial readiness and pilot definition to implementation, qualification, validation, production, and scaling.

For CMOs, RTRT can reduce physical measurement effort and restricted warehouses, detect deviations earlier, improve process control and reproducibility, and support faster batch-release decisions. Auditable per-part quality evidence can also strengthen confidence and transparency with OEM customers.

Once validated, the approach can be replicated across molds, machines, production lines, and locations. The ability to offer OEMs this level of auditable per-part release confidence can ultimately become a competitive advantage for CMOs.

Kistler supports you not only with the required technology but also with the application expertise, implementation support, validation guidance, and training needed to put it into practice.

OEMs gain a stronger evidence basis for supplier release decisions. Per-part process and quality information can improve visibility into production quality, support audits and investigations, and help establish more consistent quality expectations across the supplier network.

This is particularly relevant when components are produced across multiple molds, suppliers, production lines, or locations. Kistler works with you to define the implementation approach while supporting your CMO network in putting the technology into practice.

No. No single technology automatically ensures regulatory compliance. The measurement system, quality determination, validation approach, documentation, and release process must be integrated into the manufacturer’s approved quality management system and assessed against the respective requirements.

The Kistler MedRelease Suite provides the measurement, quality data, documentation, and implementation foundation to support you in this process.

Yes. Once the measurement and quality-determination concept has been successfully established, it can provide the foundation for consistent implementation across additional products, molds, machines, production lines, and locations.

Kistler supports you in replicating the validated RTRT approach consistently across your production and supplier networks.

A validated quality model is valid within defined operating conditions. Changes to the process, equipment, material, mold, sensor setup, or other relevant conditions, therefore, need to be assessed to determine whether they could affect the measurement or quality-determination approach.

If a change moves the process outside the validated range or affects model performance, verification or revalidation is required before the model continues to be relied on for quality determination. Kistler supports you in assessing these changes and maintaining a reliable foundation for RTRT.

Not automatically. The suitability and value of RTRT depend on the specific application, its quality and risk requirements, production volumes, current inspection effort, process stability, and the existence of a reliable relationship between cavity pressure and the relevant part quality.

A readiness assessment and pilot can help determine whether RTRT is appropriate, what level of implementation makes sense, and what needs to be validated before moving toward production use. Please contact us to set up an initial meeting.

Relevant part characteristics, current inspection effort, process stability, measurement requirements, production infrastructure, and the desired release approach all need to be considered.

A pilot provides a practical way to establish the relationship between cavity pressure and relevant part-quality characteristics and determine the appropriate path forward.

OEMs and CMOs ready to explore their potential for RTRT can talk to our experts to assess their current situation, identify opportunities and requirements, and define meaningful next steps. Contact us today.

Start with a clearly defined application and a shared objective between the relevant OEM, CMO, quality, process, and toolmakers. Kistler can help assess RTRT readiness, define the measurement concept, identify implementation and validation requirements, deliver training for team certification to establish necessary knowledge in-house, and establish a realistic path toward a first pilot.

The goal is not to replace an established quality process overnight, but to build a validated foundation for auditable per-part release confidence step by step. Contact us to identify your next step.