Reverse Engineering vertical cooling water pump

Customer Requirement:

3D design data is often unavailable for older cooling water pumps. This was precisely the problem faced by one of our customers, who wanted to optimize the pump, including the design of new components.

The assignment was to measure several pump components and create a parametric CAD model based on those measurements. The CAD model was to be fully parametric and editable by the customer to enable the manufacture of the upgraded pump components.

The cooling water pump is a vertical tube pump and is 6 meters long when installed. It is one of several pumps that ensure the cooling water supply for a power plant. The cooling water for the power plant is drawn from a nearby river. 

The vertical tube pump consists of eight major pump components that are to be further developed and optimized; therefore, given the required precision, the reverse engineering method was chosen for data generation. Furthermore, the 3D model allows for the design of the pump components to be optimally tailored to the required functionality.
 

“Our requirements for optimizing the vertical tubular pump call for a precise 3D model based on scan data. The solution provided by sigma3D GmbH has achieved this perfectly.”

- GVT - Gesellschaft für Vakuum-Technik mbH, Philipp Feld, Project Manager -

Measurement Task:

First, the tubular pump was disassembled into its individual parts. Since the 3D scan captures any contamination, the surfaces of the components are cleaned and prepared for the 3D scan. 

The pump components are measured using a combination of two measurement systems. First, a grid of measurement points is defined on the component. The measurement points are marked with measurement markers. A photogrammetry system from Hexagon AICON ETALON GmbH is used to coordinate the measurement markers. The measurement markers form the basis for the orientation of the individual images captured by the ATOS 5 scan camera from Carl Zeiss GOM Metrology GmbH.

During each individual measurement, the scan camera projects a stripe pattern onto the object’s surface using a digital projector. This stripe pattern is then captured by two cameras. Within seconds, the ATOS software calculates the 3D coordinates of up to 12 million object points per measurement. In this process, the measurement markers are automatically recognized from the photogrammetric measurement, and the individual image is transformed into the part coordinate system. The object points are then meshed into a polygonal model. The result is a 3D data set in STL format. 

Using a scan camera and the polygonal model—which serves as the basis for the reverse engineering process—a parametric 3D solid model was created for each pump component.

Result:

The 3D models generated based on the physical pump components constitute a fully-fledged design result. Thanks to the parametric structure of the CAD data, the component geometry can still be modified at a later stage, providing the customer with long-term modeling options.

Furthermore, using the created 3D model, the customer can optimally tailor the design of the pump components to the required functionality and subsequently derive 2D manufacturing drawings for new production.