Machinery Protection Systems

API STANDARD 670

FOURTH EDITION, DECEMBER 2000

Machinery Protection Systems

Downstream Segment

API STANDARD 670

FOURTH EDITION, DECEMBER 2000

SPECIAL NOTES

API publications necessarily address problems of a general nature. With respect to partic- ular circumstances, local, state, and federal laws and regulations should be reviewed.

API is not undertaking to meet the duties of employers, manufacturers, or suppliers to warn and properly train and equip their employees, and others exposed, concerning health and safety risks and precautions, nor undertaking their obligations under local, state, or fed- eral laws.

Information concerning safety and health risks and proper precautions with respect to par- ticular materials and conditions should be obtained from the employer, the manufacturer or supplier of that material, or the material safety data sheet.

Nothing contained in any API publication is to be construed as granting any right, by implication or otherwise, for the manufacture, sale, or use of any method, apparatus, or prod- uct covered by letters patent. Neither should anything contained in the publication be con- strued as insuring anyone against liability for infringement of letters patent.

Generally, API standards are reviewed and revised, reaffirmed, or withdrawn at least every five years. Sometimes a one-time extension of up to two years will be added to this review cycle. This publication will no longer be in effect five years after its publication date as an operative API standard or, where an extension has been granted, upon republication. Status of the publication can be ascertained from the API Downstream Segment [telephone (202) 682-8000]. A catalog of API publications and materials is published annually and updated quarterly by API, 1220 L Street, N.W., Washington, D.C. 20005.

This document was produced under API standardization procedures that ensure appropri- ate notification and participation in the developmental process and is designated as an API standard. Questions concerning the interpretation of the content of this standard or com- ments and questions concerning the procedures under which this standard was developed should be directed in writing to the standardization manager, American Petroleum Institute, 1220 L Street, N.W., Washington, D.C. 20005. Requests for permission to reproduce or translate all or any part of the material published herein should also be addressed to the stan- dardization manager.

API standards are published to facilitate the broad availability of proven, sound engineer- ing and operating practices. These standards are not intended to obviate the need for apply- ing sound engineering judgment regarding when and where these standards should be utilized. The formulation and publication of API standards is not intended in any way to inhibit anyone from using any other practices.

Any manufacturer marking equipment or materials in conformance with the marking requirements of an API standard is solely responsible for complying with all the applicable requirements of that standard. API does not represent, warrant, or guarantee that such prod- ucts do in fact conform to the applicable API standard.

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API Publishing Services, 1220 L Street, N.W., Washington, D.C. 20005.

Copyright © 2000 American Petroleum Institute

FOREWORD

This standard is based on the accumulated knowledge and experience of manufacturers and users of monitoring systems. The objective of the publication is to provide a purchase specifi- cation to facilitate the manufacture, procurement, installation, and testing of vibration, axial position, and bearing temperature monitoring systems for petroleum, chemical, and gas industry services.

The primary purpose of this standard is to establish minimum electromechanical require- ments. This limitation in scope is one of charter as opposed to interest and concern. Energy conservation is of concern and has become increasingly important in all aspects of equipment design, application, and operation. Thus, innovative energy-conserving approaches should be aggressively pursued by the manufacturer and the user during these steps. Alternative approaches that may result in improved energy utilization should be thoroughly investigated and brought forth. This is especially true of new equipment proposals, since the evaluation of purchase options will be based increasingly on total life costs as opposed to acquisition cost alone. Equipment manufacturers, in particular, are encouraged to suggest alternatives to those specified when such approaches achieve improved energy effectiveness and reduced total life costs without sacrifice of safety or reliability.

This standard requires the purchaser to specify certain details and features. Although it is recognized that the purchaser may desire to modify, delete, or amplify sections of this stan- dard, it is strongly recommended that such modifications, deletions, and amplifications be made by supplementing this standard, rather than by rewriting or by incorporating sections thereof into another complete standard.

API standards are published as an aid to procurement of standardized equipment and mate- rials. These standards are not intended to inhibit purchasers or producers from purchasing or producing products made to specifications other than those of API.

API publications may be used by anyone desiring to do so. Every effort has been made by the Institute to assure the accuracy and reliability of the data contained in them; however, the Institute makes no representation, warranty, or guarantee in connection with this publication and hereby expressly disclaims any liability or responsibility for loss or damage resulting from its use or for the violation of any federal, state, or municipal regulation with which this publication may conflict.

Suggested revisions are invited and should be submitted to the standardization manager, American Petroleum Institute, 1220 L Street, N.W., Washington, D.C. 20005.

IMPORTANT INFORMATION CONCERNING USE OF ASBESTOS OR ALTERNATIVE MATERIALS

Asbestos is specified or referenced for certain components of the equipment described in some API standards. It has been of extreme usefulness in minimizing fire hazards associated with petroleum processing. It has also been a universal sealing material, compatible with most refining fluid services.

Certain serious adverse health effects are associated with asbestos, among them the serious and often fatal diseases of lung cancer, asbestosis, and mesothelioma (a cancer of the chest and abdominal linings). The degree of exposure to asbestos varies with the prod- uct and the work practices involved.

Consult the most recent edition of the Occupational Safety and Health Administration (OSHA), U.S. Department of Labor, Occupational Safety and Health Standard for Asbestos, Tremolite, Anthophyllite, and Actinolite, 29 Code of Federal Regulations Section 1910.1001; the U.S. Environmental Protection Agency, National Emission Standard for Asbestos, 40 Code of Federal Regulations Sections 61.140 through 61.156; and the U.S. Environmental Protection Agency (EPA) rule on labeling requirements and phased banning of asbestos products (Sections 763.160-179).

There are currently in use and under development a number of substitute materials to replace asbestos in certain applications. Manufacturers and users are encouraged to develop and use effective substitute materials that can meet the specifications for, and operating requirements of, the equipment to which they would apply.

SAFETY AND HEALTH INFORMATION WITH RESPECT TO PARTICULAR PRODUCTS OR MATERIALS CAN BE OBTAINED FROM THE EMPLOYER, THE MANUFACTURER OR SUPPLIER OF THAT PRODUCT OR MATERIAL, OR THE MATERIAL SAFETY DATA SHEET.

1. Component Temperature Ranges 6

2. Humidity 6

3. Shock 7

4. Chemical Resistance 7

5. Accuracy 7

6. Interchangeability 9

7. Scope of Supply and Responsibility 9

1. CONVENTIONAL HARDWARE 9

   1. Radial Shaft Vibration, Axial Position, Phase Reference, Speed Sensing,

      and Piston Rod Drop Transducers 9

   2. Accelerometer-Based Casing Transducers 14

   3. Temperature Sensors 14

   4. Monitor Systems 15

   5. Wiring and Conduits 23

   6. Grounding 26

   7. Field-Installed Instruments 26

2. TRANSDUCER AND SENSOR ARRANGEMENTS 28

   1. Location and Orientation 28

   2. Mounting 34

   3. Identification of Transducers and Temperature Sensors 36

3. INSPECTION, TESTING, AND PREPARATION FOR SHIPMENT 36

   1. General 36

   2. Inspection 37

   3. Testing 37

   4. Preparation for Shipment 37

   5. Mechanical Running Test 37

   6. Field Testing 38

4. VENDOR’S DATA 38

   1. General 38

   2. Proposals 42

   3. Contract Data 43

APPENDIX A MACHINERY PROTECTION SYSTEM DATA SHEETS 45

APPENDIX B TYPICAL RESPONSIBILITY MATRIX WORKSHEET 53

APPENDIX C ACCELEROMETER APPLICATION CONSIDERATIONS 55

APPENDIX D SIGNAL CABLE 59

APPENDIX E GEARBOX CASING VIBRATION CONSIDERATIONS 61

APPENDIX F FIELD TESTING AND DOCUMENTATION REQUIREMENTS . . . 63 APPENDIX G CONTRACT DRAWING AND DATA REQUIREMENTS 67

APPENDIX H TYPICAL SYSTEM ARRANGEMENT PLANS 71

APPENDIX I SETPOINT MULTIPLIER CONSIDERATIONS 79

APPENDIX J ELECTRONIC OVERSPEED DETECTION SYSTEM CONSIDERATIONS 83

Tables

1. Machinery Protection System Accuracy Requirements 8

2. Minimum Separation Between Installed Signal and Power Cables 24

3A Accelerometer Test Points (SI) 42

3B Accelerometer Test Points (Customary Units) 42

D-1 Color Coding for Single-Circuit Thermocouple Signal Cable 60

1. Tools and Instruments Needed to Calibrate and Test Machinery

   Protection Systems 63

2. Data, Drawing, and Test Worksheet 64

1. Typical Milestone Timeline 67

2. Sample Distribution Record (Schedule) 68

1. Recommended Dimensions for Speed Sensing Surface

   When Magnetic Speed Sensors are Used 85

2. Recommended Dimensions for Non-Precision Speed Sensing Surface

   When Proximity Probe Speed Sensors are Used 85

3. Recommended Dimensions for Precision-Machined Speed Sensing Surface

When Proximity Probe Speed Sensors are Used 85

Figures

1. Machinery Protection System 4

2. Standard Monitor System Nomenclature 5

3. Transducer System Nomenclature 7

4. Typical Curves Showing Accuracy of Proximity Probe Channels 10

5. Standard Probe and Extension Cable 11

6. Standard Options for Proximity Probes and Extension Cables 12

7. Standard Magnetic Speed Sensor With Removable (Non-Integral)

   Cable and Connector 13

8. Piston Rod Drop Calculations 19

9. Piston Rod Drop Measurement Using Phase Reference Transducer

   For Triggered Mode 20

10. Typical Standard Conduit Arrangement 24

11. Typical Standard Armored Cable Arrangement 25

12. Inverted Gooseneck Trap Conduit Arrangement 26

13. System Grounding (Typical) 27

14. Standard Axial Position Probe Arrangement 29

15. Typical Piston Rod Drop Probe Arrangement 31

16. Typical Installations of Radial Bearing Temperature Sensors 33

17. Typical Installations of Radial Bearing Temperature Sensors 34

18. Typical Installation of Thrust Bearing Temperature Sensors 35

19. Calibration of Radial Monitor and Setpoints for Alarm and Shutdown 39

20. Calibration of Axial Position (Thrust) Monitor 40

21. Typical Field Calibration Graph for Radial Vibration and Axial Position 41

1. Typical Flush Mounted Accelerometer Details 56

2. Typical Non-Flush Mounted Arrangement Details for Integral-Stud

   Accelerometer 57

3. Typical Non-Flush Mounting Arrangement for Integral-Stud

Accelerometer and Armored Extension Cable 57

1. Typical System Arrangement for a Turbine With Hydrodynamic Bearings 72

2. Typical System Arrangement for a Double-Helical Gear 73

3. Typical System Arrangement for a Centrifugal Compressor

   or a Pump With Hydrodynamic Bearings 74

4. Typical System Arrangement for an Electric Motor With Sleeve Bearings 75

5. Typical System Arrangement for a Pump or Motor With Rolling

   Element Bearings 76

6. Typical System Arrangement for a Reciprocating Compressor 77

I-1 Setpoint Multiplication Example 80

1. Overspeed Protection System 83

2. Relevant Dimensions for Overspeed Sensor and Multi-Tooth Speed

Sensing Surface Application Considerations 84

J-4 Precision-Machined Overspeed Sensing Surface 86

vii

Machinery Protection Systems

1. General

   1. SCOPE

      This standard covers the minimum requirements for a machinery protection system measuring radial shaft vibra- tion, casing vibration, shaft axial position, shaft rotational speed, piston rod drop, phase reference, overspeed, and crit- ical machinery temperatures (such as bearing metal and motor windings). It covers requirements for hardware (transducer and monitor systems), installation, documenta- tion, and testing.

      Note: A bullet () at the beginning of a paragraph indicates that either a decision is required or further information is to be provided by the purchaser. This information should be indicated on the datasheets (see Appendix A); otherwise, it should be stated in the quotation request or in the order.

      
      

   2. ALTERNATIVE DESIGNS

      The machinery protection system vendor may offer alter- native designs. Equivalent metric dimensions and fasteners may be substituted as mutually agreed upon by the purchaser and the vendor.

      
      

   3. CONFLICTING REQUIREMENTS

      In case of conflict between this standard and the inquiry or order, the information included in the order shall govern.

      
      

2. References

   1. The editions of the following standards, codes, and specifications that are in effect at the time of publication of this standard shall, to the extent specified herein, form a part of this standard. The applicability of changes in standards, codes, and specifications that occur after the inquiry shall be mutually agreed upon by the purchaser and the machinery protection system vendor.

API

RP 552 Signal Transmission Systems

RP 554 Process Instrumentation and Control, Sec- tion 3, Alarm and Protective Devices

Std 610 Centrifugal Pumps for Petroleum, Heavy Duty Chemical and Gas Industry Services

Std 612 Special Purpose Steam Turbines for Petro- leum, Chemical, and Gas Industry Services

ANSI1

MC96.1 Temperature Measurement Thermocouples

1American National Standards Institute, 11 West 42nd Street, New York, New York 10036.

1

ASME2

Y14.2M Line Conventions and Lettering

PTC 20.2-1965 Overspeed Trip Systems for Steam Tur- bine-Generator Units

CENELEC3

EN50082-2 Electromagnetic Compatibility Generic

Immunity Standard. Part 2: Industrial Environment

DIN4

EN 50022 Low voltage switchgear and con-

trolgear for industrial use; mounting rails, top hat rails, 35 mm wide for snap-on mounting of equipment.

IEC5

584-1 Thermocouples, Part I: Reference Tables

IPCEA6

S-61-402 Thermoplastic-Insulated Wire and Cable

for the Transmission and Distribution of Electrical Energy

ISA7

S12.1 Definitions and Information Pertaining to Electrical Instruments in Hazardous (Classified) Locations

S12.4 Instrument Purging for Reduction of Hazardous Area Classification

S84.01 Application of Safety Instrumented Sys- tems for the Process Industries

Military Specifications8

MIL-C-39012-C Connectors, Coaxial, Radio Frequency,

General Specification for

MIL-C-39012/5F Connectors, Plug, Electrical, Coaxial,

Radio Frequency, [Series N (Cabled) Right Angle, Pin Contact, Class 2]

2American Society of Mechanical Engineers, 22 Law Drive, Box 2300, Fairfield, New Jersey 07007-2300.

3European Committee for Electrotechnical Standardization, Rue de Stassart, 35, B - 1050 Brussels.

4Deutsches Institut Fuer Normung e.V., Burggrafenstrasse 6, Post- fach 11 07, 10787 Berlin, Germany.

5International Electrotechnical Commission, 1 Rue de Varembe, Geneva, Switzerland.

6Insulated Power Cable Engineers Association, 283 Valley Road, Montclair, New Jersey 07042.

7Instrument Society of America, P.O. Box 12277, Research Triangle Park, North Carolina 27709.

8Available from Naval Publications and Forms Center, 5801 Tabor Avenue, Philadelphia, Pennsylvania 19120.