This regulation applies to the initial verification, subsequent verification and in-use inspection of pipettes. JJG 646-2006 Pipette Verification Regulation JJG646-2006 Standard download decompression password: www.bzxz.net
This regulation applies to the initial verification, subsequent verification and in-use inspection of pipettes.

National Metrology Verification Regulation of the People's Republic of China JJG646-2006
Pipette
Locomotive Pipette
Issued on 2006-12-08
Implementation on 2007-06-08
Issued by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China JJG646-2006
Verification Regulation of
Locomotive Pipette
JJG646—2006
Replaces JJG646—1990
This regulation was approved by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China on December 8, 2006, and came into effect on June 8, 2007.
Responsible unit: National Technical Committee on Flow and Capacity Metrology Main drafting unit: China National Institute of Metrology Participating unit: Shanghai Institute of Metrology and Testing Technology This regulation entrusts the National Technical Committee on Flow and Capacity Metrology to be responsible for interpreting this regulation Main drafters:
Participating drafters:
Jian Ka,
Blood Snow Song
Zhang Hongya
JJG646—2006
Caibao Qixin
(China National Institute of Metrology)
( China National Institute of Metrology)
(China National Institute of Metrology)
gvbouoo
ammonia garden full of fragrance and power
日8真a年o0
(Shanghai Testing and Metrology Technology Research Institute) all is more than good quantity capacity new comprehensive inspection single day day south celebration service type # quantity dry same industry single grass ball to be raw and ripe filling Yang Mishi Shi Shi city jade car child single melon network construction broadcast capital danger combined people foreign unreasonable shooting type training research country full open type plan 1
scope·
2 cited literature·
3 Terms and measurement units
Overview·
Metrological performance requirements
6 General technical requirements
6.1 Appearance requirements
6.2 Piston·
6.3 Regulator
6.4 Liquid suction nozzle·
6.5 Sealing·
7 Control of measuring instruments·
Verification conditions
Verification items·
7.3 Verification method
7.4 Processing of verification results:
7 .5 Verification cycle
Appendix A Schematic diagram of various types of pipettes
Appendix B K) value table.
Appendix C Pipette verification record format
Appendix D
Verification certificate inner page format
JJG646—2006
（8）)
1 Scope
JJG646—2006
Pipette verification procedure
This procedure applies to the initial verification, subsequent verification and in-use inspection of pipettes. 2 References
This procedure references the following documents:
GB6682-1992 Specifications and test methods for water for analytical laboratories. When using this procedure, attention should be paid to the use of the current valid versions of the above-mentioned references. 3 Terms and units of measurement
3.1 Pipette
A measuring instrument with a certain measuring range that can suck liquid out of a container and transfer it to another container. (Pipette, pipette gun, pipette, etc. are collectively referred to as pipettes). 3.2 Adjustable pipette
A pipette with adjustable capacity value.
3.3 Quantitative pipette
A pipette with a single capacity value.
3.4 ​​Suction nozzle
A component installed at the lower end of the pipette body, used to suck in and discharge liquid. 3.5 Display window
A window on the pipette that displays the capacity value. 3.6 Suction tube
A component connecting the pipette and the suction nozzle.
3.7 Volume regulator
A knob to adjust the volume digital display.
3.8 Unit of measurement
The unit of measurement of the pipette is L or mL.
4 Overview
The pipette is mainly used in scientific research departments such as environmental protection, medicine, and food hygiene, and is used for sampling or adding liquids in biochemical analysis and testing. It is a piston-type pipette that works on the principle of air discharge, and the capacity of the pipette is determined by the distance the piston moves in the piston sleeve.
The pipette is a measuring device, which is divided into two categories: quantitative pipette and adjustable pipette. Its type is divided into single-head type and multi-head type. Its structure consists of a display window, a capacity adjustment component, a piston, a piston sleeve, a suction tube, and a liquid suction nozzle (see Figure A.1~10).
5 Measuring performance requirements
JJG6462006
When the pipette is at a standard temperature of 20℃, its capacity allowable error and measurement repeatability should meet the requirements of Table 1. Table 1 Allowable error of capacity and measurement repeatability of pipette Nominal capacity/μL
Calibration point/nL
Allowable error of capacity
±（%)
Measurement repeatability
Nominal capacity/m
JJG646—2006
Table 1 (continued)
Calibration point/L
6 General technical requirements
6.1 Appearance requirements
Allowable error of capacity
Main (%)
Measurement repeatability
（%)
METROLOGY
The surface of the plastic shell of the pipette should be flat and smooth, without obvious shrinkage marks, scrap edges, cracks, bubbles and deformation; the surface coating of metal parts should be free of shedding, rust and delamination. 6.1.2 The main body of the pipette should have the following markings: product name, manufacturer or trademark, nominal capacity (L or mL), model specification, and factory number.
6.2 Piston
When pressing the piston of the pipette, the up and down movement should be flexible, and the division boundary should be obvious. 3
6.3 Regulator
JJG646-2006
The display window of the pipette should rotate flexibly during the capacity adjustment action, and the digital indication should be clear and complete. 6.4 Liquid suction nozzle
6.4.1 The liquid suction nozzle should be made of polypropylene material. 6.4.2 The liquid suction nozzle should not have obvious bending. The inner wall should be smooth and smooth, and there should be no residual liquid after discharging.
6.4.3 Pipettes of different specifications and models should use corresponding matching liquid suction nozzles. 6.5 Tightness
The pipette shall not have any leakage within 5s under a pressure of 0.04MPa. 7 Control of measuring instruments
Control of measuring instruments includes initial calibration, subsequent calibration and in-use inspection. 7.1 Calibration conditions
7.1.1 Calibration environment
The pipette shall be calibrated at a room temperature of (20±5)℃, and the room temperature change shall not exceed 1C/h. 7.1.2 Calibration medium
The calibration medium shall comply with the requirements of GB6682-1992 "Specifications and Test Methods for Water for Analytical Experiments" for distilled water or deionized water, and shall be placed in the laboratory 24h in advance, so that the temperature difference between it and the room temperature shall not exceed 2℃. 7.1.3 The pipette to be tested shall be placed in the laboratory 4h before calibration. 7.1.4 Calibration equipment
The main equipment must be qualified by the statutory technical organization and within the calibration cycle. The calibration equipment is shown in Table 2. Table 2 Calibration equipment
Instrument name
Electronic balance
Electronic balance
Vacuum gauge
Thermometer
Vacuum auxiliary equipment
Reagent wide-mouth bottle
Reading magnifier
Measuring range
40g/210g
(0-0.1)MPa
(0-30)℃| |tt||1X10 times
Verification stand, weighing cup with cover, etc.
Technical requirements
Graduation value 0.001mg
Graduation value 0.01mg/0.1mg
Resolution 0.01MPa
Graduation value 0.1℃
Resolution 0.1s
7.2 Verification items
Verification items are shown in Table 3.
Verification items
Fitness
JJG646—2006
Table 3 Verification items
First verification
Note: "+" indicates items to be inspected; "_" indicates items that may not be inspected. 7.3 Verification method
7.3.1 Appearance inspection
Subsequent verification
In-use inspection
Observe the pipette under inspection by visual inspection, touch or magnifying glass. The appearance should meet the requirements of Article 6.1. 7.3.2 Tightness inspection
7.3.2.1 Use a transparent wide-mouth reagent bottle filled with clean water, with three holes on the bottle stopper, and install the vacuum gauge, test glass tube and suction equipment (glass syringe can be used) on the bottle stopper respectively. 7.3.2.2 Connect the pipette to be tested with the liquid suction nozzle installed to the upper end of the test glass tube that is immersed in the liquid for 5 cm, start the suction equipment, and make the vacuum gauge pointer indicate 0.04MPa. After reaching equilibrium, it lasts for 5s. At this time, no bubbles should be generated at the lower end of the test glass tube. (See Figure 1) 06
Vacuum gauge
Test wax
Reagent bottle,
Vacuum area
Figure 1 Tightness test device
Suction port
Yan distilled water
7.3.3 Capacity verification
Use the weighing method to verify the pipette. 7.3.3.1 Preparation before calibration
JJG646—2006
The selected suction nozzle should match the suction rod of the pipette to be tested. At the lower end of the suction rod of the pipette, gently turn the suction nozzle to ensure the tightness of the pipette: and there should be no hanging water phenomenon during the process of completing several suction and discharge. Each suction nozzle of the multi-head pipette should be confirmed to be firmly installed before calibration. 7.3.3.2 Verification steps
(1) Place the weighing cup on the electronic balance. When the balance display stabilizes, press the joystick to reset the electronic balance to zero. (2) Adjust the capacity of the pipette to the volume of the test tube. (3) Hold the pipette vertically and move the needle to the verification position. Now insert the pipette nozzle into the container filled with distilled water and keep it 20~3mm below the liquid surface. Slowly release the button and leave the liquid surface after 2s. Wipe off the liquid outside the pipette nozzle (do not let the liquid flow out at this time! To avoid running away the liquid in the pipette nozzle). (4) Take out the weighing cup from the electronic balance and stop. Wait for 1 minute. Slowly push the button to the inner wall of the cup and move it upward. Slightly place the liquid outlet in the weighing cup at an angle of 45° to it. Slowly push the button down and then pipette the liquid along the weighing cup. (5) Place the weighing cup on the balance pan and record the specific value of the distilled water in the container at this time. , measure and record at the same time. The error of each measurement shall not exceed the specification in Table 1 (6). Repeat six rows (1) to (5). 7.3.4 Data processing 7.3.4.1 Pipetting capacity calculation Substitute the mass values ​​measured in 7.3 (1) to (5) into the following formula, temperature value and air density to obtain the actual capacity value of the pipette under test at the standard temperature of 20°C. UBLISHING
(20-t)
Wherein: V207
actual capacity of the transducer at standard temperature 20℃, mL;
apparent mass of the distilled water discharged by the transducer under test,
density of the air in the experiment during calibration, take 0.0012g/crPA
temperature of the distilled water at tC, g/cm2:
temperature of the distilled water during calibration, ℃.
To simplify the calculation process, formula (1) can also be transformed into the following form: V20=m·K(t)
Wherein:
K(0)=-
s[1+β(20 -t)]
P(PwA)
The K(t) value is listed in Appendix B. In this way, according to the measured value m and the K(t) value corresponding to the temperature of the distilled water during the calibration, the actual capacity value of the pipette under test at the standard temperature of 20C can be calculated. 7.3.4.2 Calculation of relative error of pipette capacity 6
JJG646-—2006
Wherein: V——nominal capacity, uL;
——arithmetic mean of six measurements, μ. 7.3.4.3 Calculation of the volume repeatability of the pipette Gm-1
Where: o-1
Standard deviation:
One calibration test
The average value of a single measurement and the measured value
7.4 Verification result
A verification certificate shall be issued to the qualified pipette (the format of the inner page of the certificate is shown in Appendix D), and a verification result notice shall be issued to the unqualified pipette (the format of the inner page of the verification result notice is the same as Appendix D), indicating the unqualified items. The verification period is 1 year.
Pipette
METROL
UBLISHING HOUSE
Appendix A
Display window 1
Pipette
JJG646-2006
Schematic diagram of various types of pipettes
Adjustment knob
Display window
Pipette nozzle
Volume regulator,
Pipette nozzle return button
Pipette control key
Suction tube
Suction nozzle
Adjustment knob
Volume regulator
Pipette nozzle return button
Pipette control key
Suction tube
Pipette nozzle0012g/crPA
The capacity of the pipette to be transferred is OLOG
The density of distilled water at tC, g/cm:
The temperature of distilled water during calibration, ℃.
To simplify the calculation process, formula (1) can also be transformed into the following form: V20=m·K(t)
Wherein:
K(0)=-
s[1+β(20 -t)]
P(PwA)
The K(t) value is listed in Appendix B. In this way, according to the measured value m and the K(t) value corresponding to the temperature of distilled water during calibration, the actual capacity value of the pipette under test at the standard temperature of 20C can be obtained. 7.3.4.2 Calculation of relative error of pipette capacity 6
JJG646-—2006
Where: V——nominal capacity, uL;
——arithmetic mean of six measurements, μ. 7.3.4.3 Calculation of repeatability of pipette capacity Gm-1
Where: o-1
Standard deviation:
One calibration test
The average value of a single measurement and the measured value
7.4 Verification result
A verification certificate shall be issued to qualified pipettes (the format of the inner page of the certificate is shown in Appendix D), and a verification result notice shall be issued to unqualified pipettes (the format of the inner page of the verification result notice is the same as Appendix D), indicating the unqualified items. The verification period is 1 year.
Pipette
METROL
UBLISHING HOUSE
Appendix A
Display window 1
Pipette
JJG646-2006
Schematic diagram of various types of pipettes
Adjustment knob
Display windowbZxz.net
Pipette nozzle
Volume regulator,
Pipette nozzle return button
Pipette control key
Suction tube
Suction nozzle
Adjustment knob
Volume regulator
Pipette nozzle return button
Pipette control key
Suction tube
Pipette nozzle0012g/crPA
The capacity of the pipette to be transferred is OLOG
The density of distilled water at tC, g/cm:
The temperature of distilled water during calibration, ℃.
To simplify the calculation process, formula (1) can also be transformed into the following form: V20=m·K(t)
Wherein:
K(0)=-
s[1+β(20 -t)]
P(PwA)
The K(t) value is listed in Appendix B. In this way, according to the measured value m and the K(t) value corresponding to the temperature of distilled water during calibration, the actual capacity value of the pipette under test at the standard temperature of 20C can be obtained. 7.3.4.2 Calculation of relative error of pipette capacity 6
JJG646-—2006
Where: V——nominal capacity, uL;
——arithmetic mean of six measurements, μ. 7.3.4.3 Calculation of repeatability of pipette capacity Gm-1
Where: o-1
Standard deviation:
One calibration test
The average value of a single measurement and the measured value
7.4 Verification result
A verification certificate shall be issued to qualified pipettes (the format of the inner page of the certificate is shown in Appendix D), and a verification result notice shall be issued to unqualified pipettes (the format of the inner page of the verification result notice is the same as Appendix D), indicating the unqualified items. The verification period is 1 year.
Pipette
METROL
UBLISHING HOUSE
Appendix A
Display window 1
Pipette
JJG646-2006
Schematic diagram of various types of pipettes
Adjustment knob
Display window
Pipette nozzle
Volume regulator,
Pipette nozzle return button
Pipette control key
Suction tube
Suction nozzle
Adjustment knob
Volume regulator
Pipette nozzle return button
Pipette control key
Suction tube
Pipette nozzle
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