The Cost Saving service is one of the key services that the Came Research and Development Department offers its customers.
As its name suggests, this service is aimed at finding a solution to reduce the cost of a product while meeting its performance requirements (wound stator in the casing and shaft-rotor).
With higher raw material prices significantly affecting sales prices, never before has this service been so strategic.
In this article I will present a case study, a project that started in mid-2020 in collaboration and agreement with a major customer in the pump sector. It resulted in Came being asked to re-think the widely used motor component kit (wound stator in the casing and shaft-rotor designed by the customer) with a view to making savings.
In particular, I’m referring to a Mec 63 4-pole single-phase 0.15 kW 230/50 motor in continuous service.
The project was divided into the following four stages:
- Standard motor characterisation on the bench
- Alternative proposal study with a view to making savings
- Building a sample and testing it on the bench
- Sample approval testing at the customer site
1. Standard motor characterisation on the bench
The first stage consisted of a full test performed on the brake bench to verify the characteristic curve (left), measure the motor input and output parameters, and verify the thermal curve (right).
The heating test at the rated load showed a significant imbalance between the two phases (main and auxiliary). This was a sign that the design was not optimised in terms of performance and maximum efficiency, but above all confirmed that performance could be improved (for the same sheet metal and copper volume) or, as in this case, that similar performance could be achieved while reducing the sheet metal and copper volume, and therefore also the motor cost.
The optimisation tests at thermal equilibrium made it possible to collect useful data for the new motor study and the proposal to the customer with a view to making savings.
2. Alternative proposal study with a view to making savings
In this second stage, we looked at dimensioning the new motor, based on the data collected and the simulation performed during the first stage.
The study resulted in a theoretical reduction of 30% in sheet metal volume and 10% reduction in copper weight. This meant a significant saving could be offered to the customer, and that the project could proceed to the next stage.
3. Building a sample and testing it on the bench
In the third stage of the project we produced drawings and data sheets, purchased the necessary material and made the alternative sample.
Once we had assembled the sample motor in our laboratory with components provided by the customer, we started the full test on the brake bench to verify, under the same load conditions, the new characteristic curve (left), measure the motor input and output parameters, and verify the new thermal curve (right).
The optimisation tests at thermal equilibrium confirmed that the proposed solution was good (full heating balance of the two phases), and allowed the motor to be tested under overload conditions up to the limit of its thermal class.
- Effective 30% reduction in sheet metal volume
- Effective 5% reduction in copper weight
- Same motor performance at the rated load
- 10% decrease in maximum torque, not significant for approval
- 15% increase in starting torque, significant for approval
- 10% reduction in input current for the same rated load
- 7% reduction in list price for the same raw material purchasing conditions
4. Sample approval testing at the customer site
In this fourth and last stage, the customer carried out the necessary approval tests (bench tests, pump test under different load conditions, life tests).
About a year after its launch, the project ended successfully with approval of the sample and launch of the first production lot.
Teamwork, available expertise and knowledge, professionalism, choice of the most qualified suppliers, and attention to the customer’s needs; these were the key points that made it possible to achieve the goal to the great satisfaction of the customer and the Came team.
Came Research and Development Expert
+39 0444 488282