Quality control of medical pipettes

Very high speed dimensional and appearance checks
Medical industry
The quality control and sorting system for medical pipettes
A qmt measuring station

Pipettes are used in the medical industry to perform small volume assays. To guarantee the accuracy of this dosage, the pipette tips must have perfect geometry and surface finish.

The production process by plastic injection of pipettes does not allow complete control of the quality. 100% automatic control is therefore necessary

qmt has developed the qmtsort-tip measuring station for the control of plastic pipettes. This checks the dimensions as well as the surface condition of the products leaving the injection machine at a rate of 20 pipettes per second.

qmtsort-tip pipette measuring station

qmt has developed and industrializes the qmtsort-tip station for 100% quality control of medical pipettes. To guarantee the precision of this dosage, the pipette tips must have a geometry as well as a perfect surface finish.

The product and the controls

qmtsort-tip controls the following 7 parameters for each tip:

  • Mes04: Surface homogeneity
  • Mes06: Presence of injection burrs inside the tip
  • Mes07: Presence of a filter

Typical dimensions of a pipette tip are an inner diameter of 0.5mm (tolerances +0.050 / 0) and an outer diameter of 0.9mm (tolerances +0.025 / -0.025).

The measuring station

The pipettes are packaged in racks, a motorized system comprising two servomotors performs the movements in order to allow scanning. In order to guarantee an optimal cycle time, qmtsort-tip includes six optical assemblies which work in parallel and are synchronized with the movement of the two axes (see diagram below). The control of a rack of 120 tips therefore represents the acquisition and processing of 120 images involving 840 results (7 controls per tip).

The system includes a standard LED transmitted light and 6 incident lights developed specifically for this application in order to guarantee a very high power and a small footprint.

The integrated computer system communicates with the entire machine through opto-isolated 24VDC digital lines and an OPC server for reference selection and traceability management.

Qmtsort-tip software

The control and supervision software has been developed so that it can be used by operators without specific IT skills. It is multi-lingual and the user interface is graphical only.

The qmtsort-tip software includes a very easy to use control program creation (reference) mode so that customers can create custom programs. The control programs are memorized and can therefore be recalled during subsequent productions.

The qmtsort-tip software allows the saving of the results as well as the images in order to allow a follow-up of the production history as well as an understanding of the detected defects.

qmtsort-tip was born from a collaboration with Zubler

qmtsort-tip is a product developed with Zubler Handling AG under. It is standardized for installation on Zubler automatic lines. qmtsort-tip is a measuring station , therefore a subset which is integrated into a complete machine. It includes hardware, software and hardware.


qmtsort-tip is a product which meets a very strong demand. It has been successfully deployed for more than 10 years with installations in Switzerland, Germany and the United States.

Manufacture of pipettes incorporating qmtsort-tip

Presentation of a Zubler pipette manufacturing machine.

qmtsort-tip is integrated into this machine

Product manager
All the components of the requirement are present: robustness for the medical industry, precision of controls and speed
Arnaud Rollin
Software developer
Fit For You (F4U)
some products

some products

F4U program
Solution on

Solution according to notebook

M4U program
OEM program

Custom product
industrialized by QMT

OEM program