NKMZ – for “General Electric”

Novokramatorsky Mashinostroitelny Zavod plans to ship three 15-ton rotor shafts to General Electric (USA) in the second quarter of 2021.

“NKMZ has been working with the GE Oil&Gas division of General Electric since 2013. At that time, our company was certified as a supplier of full-cycle finished machined parts for GE Oil&Gas, a global manufacturer of generators and electric motors for pumping gas and oil.

During this time, NKMZ has manufactured more than 3 thousand tons of products for GE Oil&Gas. Today, our strategy is aimed at further increasing the number of supplies – says Mr. Stanislav Zakharchuk, head of the rolls and power generating equipment laboratory.

The rotor shaft is a critical part, to which very high requirements are imposed on processing accuracy – value of the total mechanical runout, reflecting all the defects of its shape, should not exceed 9 microns.

Specialists of “General Electric” have developed a special technique for measuring the defect in the shape of the shaft bearing necks – runout, out-of-roundness, triangulation – with several sensors in several planes. Specialists from the rolls and power generating equipment division developed tooling and purchased the necessary equipment for this technique to ensure high accuracy of measurements.

Prior to machining, the rotor shaft blank had been subjected to a special heat treatment cycle to obtain fine and uniform grain in the metal structure, which will subsequently provide low electrical runout values, which means a low vibration when the rotor rotates in the electric motor.

The representative of the French branch of General Electric, David Thomas, carried out an expert assessment of the implementation by our specialists of the measuring technique for mechanical and electrical runouts of the rotor shaft bearing necks and gave a high assessment to the quality of machining at NKMZ”.