Most CNC machining companies will claim high-quality services and parts, but not all of these will actually deliver on their promises. Make sure CNC companies you use have ISO certification. This will usually be a sure sign that they have a high level of quality testing and provide a great service.

PT Engineers Ltd know a lot about quality and have always been keen to gain the highest level of approval. Therefore, ensuring the work we produce for our clients will not require re-work or adjustment for when these parts arrive at the next stage of manufacture.

So, what is QA and how does it compare to QC?

Quality assurance and quality control, normally known just by the initials QA & QC are often used to describe the same thing, but although they are similar, several distinct differences can be seen.

Quality Management System

The concept of QA and QC are two aspects of a quality management control system. Although QA & QC are interrelated any observer can see 2 prime differences.

Typically, QA has a range of activities. For instance: testing, recording and responsibilities covering virtually all of the operations within a work place. Whereas, QC is a partial QA activity.


Quality Assurance (QA)

Quality Assurance is defined as an integral part of a Quality System. It provides confidence that all requirements of a defined quality plan are adhered to.

Furthermore, this adherence which follows a documented set of standards and is approved by an outside agency, forms the working process within a company. External companies, agencies and government organisations normally will accept this approved system, or may still wish to do a QA Audit. Consequently, providing confidence that the parts produced are as desired.

Quality Control (QC)

Quality control is often described as part of a quality management system.

QC is normally more of an inspection, (all parts, batch, one-off or random). Therefore, ensuring that the process used in the manufacture is in-line with the data and desires of the client.

You could say that QC is ensuring that the technical and manufacturing aspects of control are adhered too.

Quality and Inspection

Quality and Inspection are prime roles for the QA team, or engineers working on each project. Inspection is the way which one measures and examines parts by means of a range of equipment.

The test equipment must be tested and approved to ensure accuracy. Moreover, it tends to be held within a defined area and include such instruments as micro-metres. These test instruments along with the supplied data, normally in the form of 2D or and 3D drawings / models check that the machined parts are within conformity.

Part of these examinations will also include checking results for suppliers, be it C of C’s from steel and other metal suppliers, to heat treatment and other out-sourced services.

PT Engineers Have Advanced Measuring Systems

Our CMM large bed machine is housed within its own controlled room (photos below). Also, our FARO arm with other types of inspection equipment are in a dedicated department, where granite tables and calibration records are allocated.

Workshop measuring equipment is at hand in the manufacturing area. This range of equipment & instruments are all assigned codes to ensure regular calibration checks & reports can be tracked.

Speak to a Specialist

PTE have a fully approved process which is documented with approval to ISO 9001. Additionally, we use a selection of handheld, Granite table based and coordinated measuring systems.

With the many CNC machining companies to choose from, it can be difficult to know who to trust. So, if you wish to have any future information on both our QA system, the work we do, or just discuss how we could aid with your production, we are always happy to help. Call us on 01788 543 661.