1. Title and functionality

1.1. MRK-01ST Container-based Mobile Rail-welding System (hereinafter referred to as the System) is designed for continuous or pulsatile fusion rail-welding on a railway track. Cross-sectional area of welded rails from 6500 mm² to 10000 mm². Automated deburring is performed immediately after welding.
Rail-welding system operating conditions:

• temperature range from - 20°С to + 40°С
• ambient air humidity up to 80% at +20°C and up to 100% at +25°C.

2. Technical specifications.

2.1. The Welding System is constructed on a rigid frame base with standard mountings for placement on a railway platform and is equipped with a hydraulic manipulator, a suspended rail-welding machine, an induction heating unit for a welded joint heat treatment, and a set of grinding machines for a rail joint treatment.

2.2. System components:

• Container unit
• Hydraulic manipulator
• Suspended flash butt rail-welding machine MSR-120.02 U1 with a control system and closed loop cooling system
• Induction heating machine UIN 001-100/RT-P for post-weld heat treatment
• VOLVO PENTA 550 kVA diesel genset
• Electric hoists for the lifting and loading of production equipment
• Spare parts kit

2.2.1. Container unit design.

The container unit (hereinafter referred to as the “container”) is used for the installation of the system equipment to ensure its safe operation and protection against environmental exposure.

The container ensures the possibility of its mounting on a railway flat car at any time of the year and in all weather and climatic conditions as well as its frequent relocation without any loss of its operating efficiency.

The container has a rectangular body 8042 х 2438 х 2900 mm (L x W x H). An external electric hoist adds 200 mm of length. The container base is a rigid welded metal frame equipped with standard fittings for installation on a flat car. The roof is made of a laminated sandwich panel, and the walls are made of shaped steel sheets. The roof of the manipulator compartment is equipped with an upward-opening hood. The interior paneling of the walls is made of shaped aluminum sheets. The floor is 4 mm shaped steel sheet. The container is equipped with side and front doors for fast access to the installed equipment. The doors are equipped with locks. Protective shutters ensure the protection of the diesel genset cooling system radiator from mechanical damage as well as guide the vented air down. The container has 24 V primary lighting, 24 V emergency lighting, and 220 V exterior lighting of the working area. The container is equipped with three-phase and single-phase 220 V electrical receptacles for powering electric tools. The container is equipped with dry powder and carbon dioxide fire extinguishers (4 pcs).

2.2.2. Hydraulic manipulator.

The hydraulic manipulator is used for the smooth positioning of the welding head on the rail joint. The manipulator is operated using controls located on the right and left sides of the manipulator as well as directly on the welding head. The hydraulic manipulator specifications are shown in Table 1 below.

Table 1

Manipulator hydraulic cylinder rods are protected with weld spatter resistant housings.
In case of power interruption, the manipulator stops automatically if its operating elements are not in a zero position. It is also possible to manually raise, lower, and retract the boom into a safe position.

2.2.3. Specifications of the MSR-120.02.U1 welding machine with control system and closed loop cooling system.
Machine specifications and dimensions are listed in Table 2 below.

Table 2

                
After welding, the machine performs automatic deburring with the subsequent return of the equipment into the initial position.
The control system is built using the Omron NX series industrial controller and ensures the following:

• Set up, adjustment, and monitoring of the quality-relevant process parameters of the welded joints
• Welding process control
• Actuators status monitoring
• Power system status monitoring
• Real-time updates on the welding process progress
• Registration and storage of welding process data for each welded joint
• Issue of certificates for each welded joint
• Self-monitoring and diagnostics

The control system automatically compares the actual and target parameters and visualizes the welding process status using diagrams and tables. Each welded joint certificate (welding report) contains the following information:

• Operator name
• Foreman name
• Welding date
• Joint number
• Rail type
• Welding conditions
• Welding duration
• Welding process oscilloscope record
• Primary welded joint conformance data based on the tolerancing results

Closed loop self-contained cooling system ensures the reliable and efficient heat removal from the welding machine electrodes and transformers. Coolant – G12 antifreeze or similar.

2.2.4. Induction heating machine UIN001-100/RT-P for post-weld heat treatment.
High frequency induction heating machine UIN 001-100/RT-P is used for post-weld heat treatment directly in track. Post-weld heat treatment is performed by the uniform heating of the entire rail cross-section in the welded joint area to a specified temperature with subsequent rail head hardening by forced cooling with compressed air.

Machine components:

• Frequency converter
• Heat treatment unit consisting of a heater, a hardening device and a heat treatment control unit.
• Compressor with receiver
• Water cooling unit
• Switching units

The UIN 001-100/RT-P machine specifications are listed in the Table 3.

Table 3

Heat treatment mode for welded joints of R65 type rails (for reference).

Heating:

• power consumption 25-75 kVA;
• heating temperature 850-900 °C;
• conversion frequency 8-15 kHz;
• post-heat interval 12±3 s;
• heating time, max. 180-245 s.

Cooling (head hardening):

• cooling time, min. 180 s;
• operating air pressure 0.5-0.8 MPa;
• air flow rate, min. 3 600 l/min.

The heat treatment process control unit provides fully automated process with minimal operator involvement and implements the following functions:

heat treatment parameters setting and monitoring (heating temperature, heating time, frequency converter power, hardening time, hardening unit air pressure);

• System equipment tech status monitoring based on signals from sensors and limit switches;
• heating treatment tech process visualization;
• data certificate creation, accumulation and storage (information about the process of the heat treatment) for each welded joint with the possibility of printing them on the built-in printer;
• shift report based on the results of the System shift work creation with the issuance of a report for each joint (valid / invalid) with the possibility of printing them on the built-in printer at the end of the shift.

To provide the required air flow a compressor with a capacity of at least 3,600 l/min (at 8 bar) with a 250-liter receiver is used.

2.2.5. Diesel generator set VOLVO-PENTA*.
The diesel generator set specifications are listed in the Table 3.

Table 3

2.2.6. Electric hoist for lifting the load onto the platform or inside the System.
Stationary electric hoist type RA is used for lifting, holding, and lowering loads as well as for moving loads horizontally.

Table 5

2.2.7. Manual grinding and rail cutting tools.

3. MRK-01ST mobile container-based rail-welding system includes1:

• Container unit;<
• Hydraulic manipulator;
• Suspended rail-welding machine MSR-120.02U1 with a control system and closed loop cooling system;
• Induction heating machine UIN 001-100/RT-P for post-weld heat treatment;
• VOLVO PENTA 550 kVA diesel genset;
• Electric hoist - 2 pcs.;
• Spare parts kit;
• Operating documentation including:
• Certificate;
• Circuit diagram;
• Hydraulic diagram;
• Control system software;
• Spare parts kit manual.

The manufacturer keeps the right to make changes to the design and configuration that do not impair the technical characteristics of the System.

4. Safety requirements.

4.1 Climatic design U, location category 1 (according to GOST 15150).
4.2. Safety requirements for the components of the System are listed in the respective component operating manuals..
4.3. Protection class of energized components is IР 20 (except for welding machine electrodes, which is IР 00) according to GOST 14254-96.
4.4. Electric shock protection class - 01 according to GOST 12.2.007.0-75.

5. Acceptance procedures.

5.1.The System acceptance procedures are carried out by the representatives of the Customer at the Manufacturer’s facility.

6. Delivery Terms and Conditions

6.1. Delivery Terms and Conditions for the MRK-01ST mobile container-based rail-welding system is carried out on the terms of ЕХW Pskov, Russia according to INCOTERMS-2010.

7. Delivery time

7.1. Delivery time for the MRK-01ST mobile container-based rail-welding system is 180 days.

8. Pre-commissioning works.

8.1. The Manufacturer performs the start-up and pre-commissioning works for the MRK-01 ST mobile container-based rail-welding system at the Customer's facility.

9. Training

9.1. The Manufacturer performs the training of the Customer’s personnel on the operation and maintenance of the System.

10. Warranty

10.1. The warranty period for the MRK-01 ST mobile container-based rail-welding system is twelve months after the commissioning date.

11. Post-warranty service and maintenance

11.1. Upon the expiration of the warranty period, the Manufacturer, if agreed with the Customer, can provide post-warranty service and carry out the maintenance of the MRK-01 ST mobile container-based rail-welding system, including maintenance schedules and supply of required spare parts.

The layout diagram of the MRK-01 ST mobile container-based rail-welding system

 

 

 

Container unit

 

VOLVO PENTA diesel genset with Stamford alternator

 

Hydraulic drive station

 

Hydraulic manipulator with rail-welding machine

 

Induction heating unit