Some standard content:
UPC 629 : 534. 1. 08
National Standard of the People's Republic of China
GB/T 14696--93
Code for the measurement of ship vibration
Promulgated on November 9, 1993
State Administration of Technical Supervision
Applied on July 1, 1994
National Standard of the People's Republic of China
Code for the measurement of ship vibration
This standard refers to the international standard ISO 4867-84 "Code for measurement and reporting of ship vibration data". Subject content and scope of application
This standard specifies the conditions and methods for measuring ship vibration and the reporting form of the measured data. GB/T 14696-93
This standard is applicable to ships sailing at sea with hull beam vibration excited by propulsion equipment. Inland vessels can also refer to it. 2 Measuring instruments
2.1 An electronic measuring system with multiple channels and long-term record keeping should be selected. It is usually composed of sensors, amplifiers, filters and recorders.
2.2 It should have a wide frequency range and amplitude linearity. It should meet the frequency and amplitude requirements of the measured components and be able to adapt to environmental conditions such as temperature, brightness and noise on board.
2.3 The sensor installation should be reliable and accurate. The direction and layout of the wires should be reasonable. 2.4 The sensitivity, amplitude-frequency characteristics, amplitude linearity and phase-frequency characteristics of the instrument must be regularly verified or calibrated, and the certificate of conformity must be obtained before use.
2.5 When the pulse device is installed on the propeller shaft, the pulse signal should correspond to the upper dead center of the No. 1 cylinder of the upper engine or the position of a certain blade of the propeller.
3 Residual conditions
3. 1 The water depth should not be less than 5 times the draft of the ship (except for special circumstances). 3.2 The sea surface should be below sea state 3.
3.3 The ship should be fully loaded or ballasted. When ballasted, the stern draft should ensure that the propeller is completely immersed in water. 3.4 The ship should maintain a stable heading and the maneuvering angle should be limited to ±2\. 3.5 When conducting the excitation test, the ship should be in a free floating state and irrelevant mechanical and electrical equipment on board should stop working. 3.6 When the above conditions cannot be met, it should be noted in the report. 4 Measurement location
4.1 Stern
The intersection of the longitudinal mid-section of the upper (main) deck and the stern end or the front compartment of the stern peak tank is the main characteristic point of the hull beam vibration. The measurement base directions are vertical, transverse and longitudinal. When measuring the torsional vibration of the hull, a pair of vertical sensors should be installed on both sides of the stern and upper (main) deck. See Figure 1. Approved by the State Administration of Technical Supervision on November 9, 1993 and implemented on July 1, 1994
W4.2 Superstructure
GB/T14696-93
Figure 1 Schematic diagram of hull vibration measurement
The intersection of the centerline of the bridge deck and the front wall is the overall vibration characterization point of the superstructure. The measurement directions are vertical, transverse and longitudinal. See Figure I
4.3 Hull beam (optional measurement item)
4.3.1 The hull beam bending vibration measurement points are arranged on the upper (main) deck and the main transverse bulkheads along the length of the ship. The measurement directions are vertical and transverse. See Figure 1.
4.3.2 The ship's torsional vibration measurement points are arranged on the upper (main) deck and the main transverse bulkheads along the length of the ship. Pairs of vertical sensors are installed on both sides. See Figure 1.
4.4 Main engine and thrust bearing box
4.4.1 Gear drive
4.4.1.1 Top of thrust bearing box, measuring direction is vertical, transverse and longitudinal. See Figure 2. Vertical
Transmission
Figure 2 Schematic diagram of measuring points of thrust bearing box of gear drive main engine4.4.1.2 Thrust bearing box base, measuring direction is longitudinal. See Figure 2.4.4.2 Diesel engine direct drive
4.4.2-1 Top of the front end of the upper engine, measuring direction is vertical, transverse and longitudinal. See Figure 3.3
W Transducer position
GB/T 14696 --.93
Figure 3 Main engine (direct drive) dynamic measurement point diagram 4.4.2.2 Top of the rear end of the main engine, the measurement direction is vertical and horizontal. See Figure 3. 4.4.2.3 Front and rear ends of the main engine base. The measurement direction is vertical and horizontal. See Figure 3. 4.4-2.4 For the main engine with elastic support, the front and rear ends of the main engine bottom need to be measured, and the measurement direction is vertical and horizontal. 4.4.2.5 Thrust bearing box and its seat are in accordance with 4.4.1.1 and 4.4.1.2. 4.5 Shaft system
4.5.1 Shaft system vibration (optional measurement item) The measurement point is generally selected on the shaft section of the last intermediate bearing and the tail shaft tube, or arranged at the most vibrating place, and the measurement point is generally not less than 2. Measure the vertical and lateral vibration of the shaft relative to the tail shaft. 4. 5. 2 Shafting torsion vibration
Select a suitable torsional vibration measuring instrument. The measuring point for measuring angular displacement is generally selected at the free end of the propulsion device, and there should be no less than 2 measuring points. 4.6 Hull pulsation pressure measuring point (optional) Measure the pulsation pressure on the hull surface caused by the propeller. At least three measuring points should be arranged, two of which are installed roughly above the propeller disk, and the other sensor is installed about 0.1D in front of the propeller disk (D is the diameter of the propeller). In order to reduce the impact of the vibration of the bottom plate, all sensors should be installed as close to the auxiliary plate or half bulkhead as possible. On the bottom plate at the position of the ship. See Figure 1. WGB/T14696-93
Transducer location
Figure 4 Hull pulsation pressure sensor location
4.7 The above-mentioned measuring plate position can be selected according to the measurement purpose and requirements. 5 Quantity substitution
The measurement parameters should include:
Displacement, mml
Speed: mm/s+
Acceleration, mm/g°,
Pressure, MPa;
Frequency, Hzt
Phase, \).
Parameters a. to d. are all expressed as single peak values. 6 Measurement procedure
6.1 Calibration
6. 7. 1 After all the measuring instruments are installed and connected on site, each channel must be debugged and the appropriate range must be selected to ensure normal operation. 6.1.2 Before and after the measurement, conduct on-site calibration for each channel to repeat the system calibration status in the laboratory and make on-site records. 6.2 Test continuation
6.2. 1 In the stable speed range of the main engine, scan the stable speed rate or deceleration rate at about 3% of the rated speed of the main engine and record it in a book to determine the critical speed.
6-2.2 During the test, the main engine speed starts from half of the rated speed, and increases by 5~10r/min for low-speed engines, 10~50r/min for medium-speed engines, and 50~100r/min for high-speed engines until the rated speed. The speed level should be appropriately increased near the resonance speed and operating speed. The measurement record should be carried out after each speed level is stable: 6.2.3 Perform a sharp left turn or sharp right turn test at the maximum speed (optional test item). 6.2.4 Perform a rapid reverse test from full speed forward to full speed reverse (optional test item). 6.2.5 Excitation test
.6.2.5.1 Anchor test
GB/T 14696-93
The ship is floating on the sea surface, and the anchor is freely dropped. The anchor brake is used to brake rapidly before the anchor touches the bottom. The signal should be continuously recorded from the time the anchor is loosened until the vibration stops. The measurement point arrangement is shown in Figure 1.6.2.5.2 Microvibrator test
Different grades of exciters are selected according to the different tonnages of the ship and installed on the tail strength member. The upper exciter starts from the lowest speed and increases slowly and steadily. The speed of the exciter is preferably 5 to 10 T/mm. The speed can be appropriately increased near the resonance frequency. The speed of each speed is recorded synchronously. The natural frequency, vibration damping and resonance curve of each order of the hull depth are obtained. 7 Data collection, analysis and provision
7.1 Data collection
7.1.1 The continuous time of signal recording shall not be less than 60 s. 7.1.2 When recording measurement data, the pulse signal and vibration response signal must be recorded step by step. 7.2 Data analysis
7.2.1 Random truncation or full cycle truncation method can be used for computer analysis. 7.2.-2 The sampling time △T of fast Fourier transform (FFI) is generally 4 s. The frequency resolution is calculated as follows: Where; F
: frequency resolution. IIz
Sampling time, s,
7.3 Data provision
7.3.1 Provide the vibration amplitudes of shaft frequency, blade frequency and blade frequency caused by the propeller and the vibration amplitudes of the main frequency components caused by the main engine. 7.3.2 Provide the natural frequencies, vibration modes, damping and resonance curves of the hull. 7.3.3 Provide the phase-frequency relationship between the hull girder vibration and the whirling vibration and torsional vibration of the shafting. 7.3.4 Provide the machine-frequency relationship between the main engine and the whirling vibration and torsional vibration of the shafting. 7.3.5 When the hull girder is seriously affected by the main engine or propeller excitation, the response amplitude of the measuring points in 4.1 and 4.2 is to be provided. 7.3.6 When there is "beat vibration", provide the "beat" frequency and maximum and minimum amplitudes. 8 Data report
8.1 Main design parameters of the ship
8.1.1 Fill in the main parameters of the ship and propulsion device according to Table A1 and Table A2 of Appendix A (reference). 8.1.2 Provide a longitudinal plane diagram of the hull and superstructure. 8.1.3 Provide a stern line diagram
8.2 Measurement point distribution diagram.
8.3 Fill in the test conditions according to Table A3 of Appendix A (reference). 8.4 Fill in the vibration measurement results according to Table A4 and Table A5 of Appendix A (reference). 8.5 Provide the frequency, vibration mode, damping and resonance curves of each value of the general beam. 8. 6 Fill in the report required for other selected items according to Table A6 in Appendix A (reference work). 8.7 Provide the analysis method of test data.
8.8 Evaluate the measurement results according to the corresponding evaluation standards and Figure 5. Wumn
GB/T 14696—93
Figure 5 Plotting diagram of ship vibration data
W General name
Manufacturer/year of construction
Ship type and model
Formula
According to line length Imm
Breadth Rm
Deepth H+m
Draft (full load) fm
Select to (full load) 4.1
Square coefficient C
Load Dt
Medium moment, nt*
Medium section shear area.㎡
Medium surface diagram:
GB/T14696-93
Appendix A
Example of ship perturbation measurement data table||tt ||(Test material)
Main parameters of the test ship
Months, engine type and model
Year of construction
Diameter and stroke, mm
Power kW
Speed, r/min
Unbalanced torque
Screw type
Diameter D, n
Speed, r/min
Propeller blade tilt angle, (\)
Pitch ratio
Space ratio C/D
Energy type and number
Simple diagram of propeller hull clearance,
W6
Main parameters of propulsion shaft system
Rotating part
GB/T 14696 -. 93
Diameter, mn
Length+mm
First intermediate shaft
Second intermediate shaft
Third intermediate shaft
Fourth intermediate shaft
Drive shaft
Second reduction
Gear box
First reduction
Gear box
Assisted by the Ministry of Civil Affairs
Your propeller mass (e> and density (kg/m\)
Propeller mass moment of inertia tm
Distance between propeller center of gravity and tail shaft
Rear support
Between two shaft supports
Intermediate bearing
Mass polar moment of inertia
Main parameters of propulsion shaft system
Maximum speed and belt speed-/inin
Village sleeve material model
Shaft alignment (direct or theoretical alignment)
Stationary part
Diameter, mm, mm
Rear bearing of tube
Front bearing of tube|| tt||First intermediate bearing
Second intermediate bearing
Third intermediate bearing
Fourth intermediate bearing
Fifth intermediate bearing
Sixth intermediate bearing
Seventh intermediate bearing
Eighth intermediate auxiliary bearing
Ninth intermediate bearing
Thrust bearing
Main gear assembly, rear bearing
Main gear assembly bearing
Relay shaft ratio change its basic diagram (marking the main dimensions) distance height|| tt||Simple diagram of the shaft system indicating the relative position of the rotating part and the stationary part, 8
W. Point
Number of points:
Test conditions
Sea conditions (full wind force)
Relative angle, (\)
Draught + m
Draught + m
Average draft, m
Water level during the test, t
Submerged depth of propeller, t
Frequency
Propeller
GB/T 14696-93
丧A3 Conditions for vibration measurement
Instrument model:
TableA4 Vibration measurement results
Measurement date:
|Person filling out the form,
Amplitude and frequency
TableA5 Results of shaft torsional vibration measurement
Tangku terminal
Frequency harmonic
fnMemD
Frequency harmonic
Inspector,
Instrument=
W Maneuvering condition
Full left rudder
Emergency reverse
Remarks:
Ship name:
Additional instructions:
Shaft speed
GB/T 14696-93
Table A6 Vibration measurement results during ship maneuvering (optional items) Maximum amplitude loss and frequency
Frequency component
TimeWww.bzxZ.net
Time
Time
Time
Term:
Form filler:
This standard is proposed by the National Technical Committee for Standardization of Mechanical Vibration and Shock. Longitudinal
Others
Shuttle Tester:
This standard is under the jurisdiction of the National Technical Committee for Standardization of Ocean-going Vessels and the National Technical Committee for Standardization of Mechanical Vibration and Shock. This standard was drafted by the 702 Institute of the Seventh Research Institute of China State Shipbuilding Corporation. The drafters of this standard are Hu Jing and You Qixiang.
W..n
Speed, r/min
Blade tilt angle, (\)
Pitch ratio
Space ratio C/D
Energy type and number
Simplified diagram of propeller hull clearance,
W6
Main parameters of propulsion shaft system
Rotating part
GB/T 14696 -. 93
Diameter, mn
Length+mm
First intermediate shaft
Second intermediate shaft
Third intermediate shaft
Fourth intermediate shaft
Drive shaft
Second reduction
Gear box
First reduction
Gear box
Assisted by the Ministry of Civil Affairs
Your propeller mass (e> and density (kg/m\)
Propeller mass moment of inertia tm
Distance between propeller center of gravity and tail shaft
Rear support
Between two shaft supports
Intermediate bearing
Mass polar moment of inertia
Main parameters of propulsion shaft system
Maximum speed and belt speed-/inin
Village sleeve material model
Shaft alignment (direct or theoretical alignment)
Stationary part
Diameter, mm, mm
Rear bearing of tube
Front bearing of tube|| tt||First intermediate bearing
Second intermediate bearing
Third intermediate bearing
Fourth intermediate bearing
Fifth intermediate bearing
Sixth intermediate bearing
Seventh intermediate bearing
Eighth intermediate auxiliary bearing
Ninth intermediate bearing
Thrust bearing
Main gear assembly, rear bearing
Main gear assembly bearing
Relay shaft ratio change its basic diagram (marking the main dimensions) distance height|| tt||Simple diagram of the shaft system indicating the relative position of the rotating part and the stationary part, 8
W. Point
Number of points:
Test conditions
Sea conditions (full wind force)
Relative angle, (\)
Draught + m
Draught + m
Average draft, m
Water level during the test, t
Submerged depth of propeller, t
Frequency
Propeller
GB/T 14696-93
丧A3 Conditions for vibration measurement
Instrument model:
TableA4 Vibration measurement results
Measurement date:
|Person filling out the form,
Amplitude and frequency
TableA5 Results of shaft torsional vibration measurement
Tangku terminal
Frequency harmonic
fnMemD
Frequency harmonic
Inspector,
Instrument=
W Maneuvering condition
Full left rudder
Emergency reverse
Remarks:
Ship name:
Additional instructions:
Shaft speed
GB/T 14696-93
Table A6 Vibration measurement results during ship maneuvering (optional items) Maximum amplitude loss and frequency
Frequency component
Time
Time
Time
Time
Term:
Form filler:
This standard is proposed by the National Technical Committee for Standardization of Mechanical Vibration and Shock. Longitudinal
Others
Shuttle Tester:
This standard is under the jurisdiction of the National Technical Committee for Standardization of Ocean-going Vessels and the National Technical Committee for Standardization of Mechanical Vibration and Shock. This standard was drafted by the 702 Institute of the Seventh Research Institute of China State Shipbuilding Corporation. The drafters of this standard are Hu Jing and You Qixiang.
W..n
Speed, r/min
Blade tilt angle, (\)
Pitch ratio
Space ratio C/D
Energy type and number
Simplified diagram of propeller hull clearance,
W6
Main parameters of propulsion shaft system
Rotating part
GB/T 14696 -. 93
Diameter, mn
Length+mm
First intermediate shaft
Second intermediate shaft
Third intermediate shaft
Fourth intermediate shaft
Drive shaft
Second reduction
Gear box
First reduction
Gear box
Assisted by the Ministry of Civil Affairs
Your propeller mass (e> and density (kg/m\)
Propeller mass moment of inertia tm
Distance between propeller center of gravity and tail shaft
Rear support
Between two shaft supports
Intermediate bearing
Mass polar moment of inertia
Main parameters of propulsion shaft system
Maximum speed and belt speed-/inin
Village sleeve material model
Shaft alignment (direct or theoretical alignment)
Stationary part
Diameter, mm, mm
Rear bearing of tube
Front bearing of tube|| tt||First intermediate bearing
Second intermediate bearing
Third intermediate bearing
Fourth intermediate bearing
Fifth intermediate bearing
Sixth intermediate bearing
Seventh intermediate bearing
Eighth intermediate auxiliary bearing
Ninth intermediate bearing
Thrust bearing
Main gear assembly, rear bearing
Main gear assembly bearing
Relay shaft ratio change its basic diagram (marking the main dimensions) distance height|| tt||Simple diagram of the shaft system indicating the relative position of the rotating part and the stationary part, 8
W. Point
Number of points:
Test conditions
Sea conditions (full wind force)
Relative angle, (\)
Draught + m
Draught + m
Average draft, m
Water level during the test, t
Submerged depth of propeller, t
Frequency
Propeller
GB/T 14696-93
丧A3 Conditions for vibration measurement
Instrument model:
TableA4 Vibration measurement results
Measurement date:
|Person filling out the form,
Amplitude and frequency
TableA5 Results of shaft torsional vibration measurement
Tangku terminal
Frequency harmonic
fnMemD
Frequency harmonic
Inspector,
Instrument=
W Maneuvering condition
Full left rudder
Emergency reverse
Remarks:
Ship name:
Additional instructions:
Shaft speed
GB/T 14696-93
Table A6 Vibration measurement results during ship maneuvering (optional items) Maximum amplitude loss and frequency
Frequency component
Time
Time
Time
Time
Term:
Form filler:
This standard is proposed by the National Technical Committee for Standardization of Mechanical Vibration and Shock. Longitudinal
Others
Shuttle Tester:
This standard is under the jurisdiction of the National Technical Committee for Standardization of Ocean-going Vessels and the National Technical Committee for Standardization of Mechanical Vibration and Shock. This standard was drafted by the 702 Institute of the Seventh Research Institute of China State Shipbuilding Corporation. The drafters of this standard are Hu Jing and You Qixiang.
W..
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