Koepe type 4-rope hoisting machine with direct AC synchronous drive at KGHM PM S.A. “Rudna” Mining Plant

The main objective of the project was to replace the worn-out hoisting machine with a modern, more functional, energy-efficient one using a synchronous electric motor.

Scope of the project

  • replacement of the hoisting machine,
  • replacement of the shaft signalling and communication system,
  • replacement of shaft machinery components,
  • replacement of shaft equipment components,
  • development of technical documentation for the entire task,
  • supply and installation of the machinery and equipment,
  • cooperation with mining supervisory authorities,
  • commissioning and servicing of supplied equipment.

4L-4000/AC-12m/s hoisting machine

The 4L-4000/AC-12m/s hoisting machine is the first in Poland to be driven by a gearless low-speed synchronous motor powered by an AC frequency converter.

The main components of the mechanical part are:

  • drive drum,
  • main shaft with bearings,
  • bearing lubrication unit,
  • mounting elements,
  • braking system including power supply, control and gravity overload lowering system.

The shaft and bearing housings were adapted to accommodate split roller bearings. If the positioning bearing needs to be replaced, the applied solution allows to reduce the time for bearing replacement several-fold.

A forced flow of lubricant from an external lubricating unit along with control sensors system ensures proper lubrication of spherical roller bearings and monitoring of bearing parameters.

The bearing assemblies are galvanically isolated and provided with a shaft current dissipation system.

The electrohydraulic brake control and supply unit comprises two hydraulic units: primary and backup. The redundancy of units ensures continuous operation of the hoisting machine brake.

The hydraulic units enable the selection of two values of braking force during emergency braking which has a positive effect on the components of the shaft hoist (cables, vessel guidance, suspensions).

The main components of the electrical part of the hoisting machine and the shaft signalling and communication system are:

  • synchronous, low-speed electric motor,
  • frequency converters supply transformers,
  • main circuit frequency converters,
  • main circuit configuration change switch,
  • complete cooling system for the drive motor and frequency converters,
  • 400/230 VAC switchgear,
  • control and safety system for the hoisting machine,
  • digital drive controller and speed control system,
  • shaft signalling and communication system,
  • visualisation system,
  • video surveillance system for all levels of the shaft entry and shaft top infrastructure,
  • ECHO-S type control signalling and communication system,
  • recording device,
  • optical fibre cables for control, signalling and telecommunications,
  • system for measuring and dissipation of bearing currents,
  • shaft signalling telephone exchange including receivers at all stations and in the signalling cabin.

The use of a synchronous, low-speed motor as a drive motor enabled reducing reactive power and higher harmonics.

The use of a double drive consisting of two SINAMICS S120CM frequency converters in the main circuit and two SINAMICS DCM frequency converters in the excitation circuit increased the operational reliability of the hoisting machine.

The digital drive controller and speed control system enables the control of hoisting machine’s travel diagram according to the requirements of the user, taking the character of the mine shaft hoist into account.

The control system, protection equipment, digital drive controller of the hoisting machine and the control and signalling system are based on a redundant logic controller system. The system of redundant logic controllers allows for a high level of safety and reliability in the operation of the aforementioned systems.

Visualisation of all elements of the hoisting machine and the control and signalling system on the touch screen monitor of an industrial computer provides parameters display and gives enables the control of the status of the equipment in real time.

The modular design of the control and signalling system enables quick replacement of damaged components.

As part of the modernisation of shaft equipment, automatically controlled air-operated shaft gates were used.

A state-of-the-art RA1 automatic shaft gate lock, developed and manufactured by MWM Elektro Sp. z o.o., was used to open and close the shaft gates. The RA1 automatic lock enables control of the shaft gates, while keeping them securely and safely locked.

Catalogue chart – RA1 shaft gate lock

As part of the modernisation of the mining shaft hoist, MWM Elektro sp. z o.o. provided the following:

  • adjustment of the guiding pulley support structure to replace the hoisting cables at the skip compartment entry level,
  • upgrading the rigid cage conveyance guidance with additional supports below the shaft entry level,
  • installation of front guides.

Additional equipment included in the comprehensive modernisation:

  • complete CCTV system with monitored stations,
  • vibration and temperature monitoring system for the bearings of the hoisting machine and guiding pulleys,
  • set of equipment for replacement and inspection of main bearings,
  • engineering stations with software,
  • hoisting machine operating cabin.

Technical specifications of the 4L-4000/AC-12m/s type hoisting machine:

number of hoisting cables 4
winding diameter of the hoisting cables on the winder 4000 mm
maximum speed 12 m/s
diameter of hoisting cables 44 mm
personnel transport 10,8 Mg
materials transport 23,6 Mg
power supply parameters:
hoisting machine 6 kV, 500 VAC
auxiliary circuits 500 VAC, 230 VAC, 24 VDC
primary parameters of the drive motor:
power Pn = 2500 kW
RPM nn = 57 rpm

Photo gallery

Photo 1 - Type 4L-4000/AC-12m/s hoisting machine

Photo 2 – Column with two pairs of brake cylinders

Photo 3 - Brake control and power supply unit

Photo 4 – Cooling system for the main motor

Photo 5 - Frequency converters supply transformers

Photo 6 - Main circuit busbars

Photo 7 - View of the main circuit frequency converter cabinet

Photo 8 - View of the cabinets for the control and protection system of the hoisting machine and the shaft signalling system

Photo 9 - Example screen view of the interactive visualisation system

Photo 10 – Hoisting machine operator’s station

Photo 11 - Signalling station

Photo 12 - Automatic shaft gate lock