IEC TS 60034-34:2020

Rotating electrical machines - Part 34: AC adjustable speed rolling mill motors

IEC TS 60034-34:2020 is applicable to AC adjustable speed rolling mill motors and identifies specific requirements for AC adjustable speed rolling mill motors, where those performance characteristics are different from those for conventional AC motors.
Various types of overload capacity conditions and overloads are defined. The possible effect on motor insulation life due to operating the motor beyond its design capability is discussed.
Requirements for confirmation of motor under specified variable speed operational conditions are introduced.

General Information

• Status: Published
• Publication Date: 18-Nov-2020
• ICS: 29.160.01 - Rotating machinery in general
• Technical Committee: TC 2 - Rotating machinery
• Drafting Committee: MT 15 - TC 2/MT 15
• Current Stage: PPUB - Publication issued
• Start Date: 11-Dec-2020
• Completion Date: 19-Nov-2020

Standards Content (Sample)

IEC TS 60034-34 ®
Edition 1.0 2020-11
TECHNICAL
SPECIFICATION
colour
inside
Rotating electrical machines –
Part 34: AC adjustable speed rolling mill motors

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IEC TS 60034-34 ®
Edition 1.0 2020-11
TECHNICAL
SPECIFICATION
colour
inside
Rotating electrical machines –

Part 34: AC adjustable speed rolling mill motors

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.160.01 ISBN 978-2-8322-9046-0

– 2 – IEC TS 60034-34:2020 © IEC 2020
CONTENTS
FOREWORD . 6
INTRODUCTION . 8
1 Scope . 9
2 Normative references . 9
3 Terms and definitions . 9
3.1 Terms and definitions . 9
3.2 Terms and definitions for adjustable speed control and rolling operation . 13
3.3 Terms and definitions for adjustable speed drive system . 14
3.4 Terms and definitions for monitoring and protection sequence . 15
3.5 Terms and definitions for motor installation and site trial operation . 15
3.6 Terms and definitions for test . 16
4 Terminal voltage determination . 17
5 Duty type and temperature class . 19
5.1 General . 19
5.2 Selection of rolling operation pattern . 19
5.3 Evaluation of winding temperature deviation during one rolling cycle . 20
5.4 Duty type S1 or S9 selection . 20
5.5 Class B rise or Class F rise selection . 21
5.6 Overload current duration time limit based on winding temperature deviation
in one rolling cycle for RMS current of 100 % . 21
6 Continuous overload capability . 22
6.1 General . 22
6.2 Relative thermal life index of TL value estimation by simplified method . 23
6.3 Relative thermal life estimation by precise method . 24
6.4 Relative thermal life index of TL value determination by precise method . 25
7 Mechanical requirements . 25
7.1 General . 25
7.2 Mechanical strength for shaft and other transmission parts considering
torsional vibration . 25
7.3 Vibration transmitted through the motor base . 25
7.4 Tangential forces applied to rotor and stator . 25
7.5 Thrust load . 25
7.5.1 General . 25
7.5.2 Frequently applied thrust load . 25
7.5.3 Occasionally applied maximum thrust load . 26
7.5.4 Emergency maximum thrust load . 26
7.6 Radial load for bearings . 26
7.7 Overspeed . 26
7.8 Stator coil end fixation . 26
7.9 Stator shift construction for maintenance inspection. 26
7.10 Mounting code application . 26
8 Withstand voltage capability . 26
8.1 Rotor bars or damper bars and short-circuit rings . 26
8.2 General . 27
8.3 Withstand voltage test . 27
8.4 Withstand voltage capability . 27

8.4.1 General . 27
8.4.2 Ground insulation . 27
8.4.3 Turn-to-turn insulation . 29
9 Factory tests and recommended site operation tests . 29
9.1 General . 29
9.1.1 General scope for the tests . 29
9.1.2 Requirements of the site operation test where vector control is applied . 29
9.2 Factory test . 30
9.3 Preparation before trial operation at site . 30
9.3.1 General . 30
9.3.2 Calibration of feedback signals for the converter . 31
9.3.3 Insulation resistance tests for motor . 31
9.3.4 Insulation resistance tests for bearings . 31
9.3.5 Performance test for bearing lubrication oil supply unit . 31
9.3.6 Confirmation of lubrication oil surface level for bearings . 31
9.3.7 Performance test for cooling systems . 31
9.3.8 Confirmation of alarm issue levels for motor protection . 31
9.3.9 Synchronous motor pole position confirmation test . 32
9.4 Site uncoupled trial operation . 32
9.4.1 General . 32
9.4.2 Rotational speed build-up test . 32
9.4.3 Bearing temperature rise test . 32
9.5 Site no-load characteristic test . 32
9.5.1 Induction motor no-load characteristics test . 32
9.5.2 Synchronous motor no-load characteristics test . 33
9.5.3 No-load characteristics test record. 33
9.6 Site acceleration and deceleration test . 33
10 Grounding . 34
10.1 General . 34
10.2 Protection against bearing currents . 34
10.3 Protective earthing (PE) . 34
10.4 Functional earthing (FE) . 34
11 Rating plate . 35
Annex A (normative) Short-time overload capability . 36
A.1 General . 36
A.2 Frequently applied Art-1 short-time overload capability specification . 36
A.3 Frequently applied Art-2 short-time overload capability specification . 39
Annex B (normative) Rolling operation pattern designation . 42
B.1 General . 42
B.2 Rolling operation pattern for hot reversing rolling . 42
B.3 Rolling operation pattern for hot continuous rolling of sheet strip . 43
B.4 Rolling operation pattern for continuous caster directly connected hot
continuous rolling mills . 44
B.5 Rolling operation pattern for hot continuous rolling for wire and rod mills . 45
B.6 Rolling operation pattern for cold reversing rolling mills . 46
B.7 Rolling operation pattern for cold continuous rolling . 47
B.8 Operation pattern for coilers and reels . 48
Annex C (informative) Determination of winding temperature deviation in one rolling
cycle . 50

– 4 – IEC TS 60034-34:2020 © IEC 2020
C.1 General . 50
C.2 Simplified method for estimation of the winding temperature deviation
between maximum and mean values in one rolling cycle . 50
C.3 Precise method for estimation of the winding temperature deviation between
maximum and mean in one rolling cycle .
...