The Precision and Technology behind Conrod Multi-Gauging!

After our last post on the multi-gauging of a cylinder block and head, we take you through the multi-gauging of one of the most important components inside a cylinder block. The amount of precision that goes into the manufacturing of these parts can be understood when we study the precise measures used to achieve the quality standards required.

The Conrod Multigauging Station is a high speed performing machine made of a robust structure with its entire X & Y axis Precision Movements controlled by high definition FLC/PLC Controllers, Hydraulic Cylinders, Precision Slides and in- house customized software to suit the shop floor condition and environment for 100% inspection of all the manufactured components having Repeatability and Reproducibility (R&R) within 10% of the total tolerance.

The assembly inside a cylinder block is one of the most critical and precise piece of engineering. The quality desired can only be achieved with multi-gauging stations that precisely gauge the parameters with R&R within 10% of the total tolerance.

Parameters measured by a Conrod Multigauging System

Some of the Parameters inspected are Big End (Crank Bore) Diameter, Ovality and Taper, Small End (Piston Bore) Diameter, Ovality and Taper, Centre Distance, Bend, Twist, Big End Squareness, Width of both ends, Stem thickness.


The actual gauging is done by precise LVDT probes which make numerous readings during the process. These readings taken from the machined surfaces of the Conrod become the basis of measurement of all parameters of the Conrod.

The Critical Job done by the Software in the System

Parameters such as bend and twist are determined by the in built software after crunching the numbers received from the LVDT probes. Each program is designed according to the needs of the client and the SPC analysis desired.

Thousands of readings and reports generated by the software are saved and used whenever needed by the manufacturer, which in turn increases the productivity and gives a quality-conscious client a complete database that can be used as a blueprint for future design and manufacturing alterations.

conrod parameters

System Integrated weighing and Quality Marking

A marking machine which may be a laser, dot pin etc can be used to mark the Conrod after measurement engraving the particular grade of the conrod along with its weight for unique identification.

A weight machine is often integrated with the system in order to grade the conrod according to its weight. The weight machine is a high accuracy machine which has a least count of 0.1 grams.

Automated or Manual Grading

The system has automated/manual grading bins in order to place the different conrod’s as per the grades indentified by the gauging station.

This makes the entire process totally operator friendly and error free.

In automated grading bins, only the flap of a particular bin is opened with the help of pneumatics depending upon the feedback received from the gauging station after gauging of the conrod has been done, so the operator can place the conrod only in that bin, since all the other bins are closed.

Sneak Peak into a Conrod Multigauging Station

The video below takes you through the complete process on the TASK Conrod Multi-gauging System!

In manual grading bins, led indicators are present above different bins. Only the led light above the correct bin flashes depending upon the feedback received from the gauging station after gauging of the conrod has been done.

If the operator places the conrod in the wrong bin, an alarm is sounded and further gauging cannot be done unless the conrod is placed in the right grade bin.

grading bins in a conrod gauging station

Acceptance of the System

The automated system will confirm R&R norms for acceptance by total component variation method covering full range of tolerance. If components covering full range of tolerance  are not available then appropriate masters covering full range are used as components. R&R study has to be within 10% for acceptance of the system.