MRC YDZ-50K User manual

SELF-PRESSURIZED SERIES FOR LN2 STORAGE AND SUPPLY
OPERATING MANUAL
YDZ-50/100K/200K
Pleasereadthis instruction carefully before us ·
The company reserves the right to explain the instructions
The appearance of the product is subject to the actual product
Please keep the invoice together after reading
No further notice in case of product technology or software upgrad
2-06-A

The liquid nitrogen supply and storage series products produced by our company are widely
applied to the sectors such as livestock, medical treatment, scientific research and industry,
and our company provides good containers for storage, transport and supply of liquid
nitrogen.
Our company is a specialized enterprise producing liquid nitrogen supply and storage
series. Our products are produced in strict accordance with Autoboosting Caliber Liquid
Nitrogen Container (GB/T 16774-2012).
PRODUCT FEATURES
1. It is convenient to fill liquid nitrogen: It is only required to unscrew the locking nut at the
liquid nitrogen filling port or the level meter to fill the drain port of the liquid nitrogen machine
fractionating tower or the pipe.
2. The container adopts the boosting method of applying a pressure to the liner after
vaporization of a little liquid nitrogen, which has the advantages of convenient operation and
rapid boosting and guarantees the purity of liquid nitrogen.
3. The container has high strength and it is suitable for short-distance transport.
4. The container has a very low drain pressure and it is installed with a pressure gauge, a
safety valve and a vacuum sealing joint. Therefore, the container is safe in use and highly
reliable.
5. The shell, the liner and the main parts and components are made of austenitic stainless
steel, without outstanding vacuum degree and cryopreservation property.
1

CONTENTS
Product Overview
Safety Precautions
Product Introduction
Product Use
Introduction and Use of Level Meter
Maintenance and Servicing
Common Problems
Packing List
1
3
4
9
13
17
19
20
32
Dear user of MRC
Hello! Thank you for choosing MRC Self-pressurized Series for LN2 Storage and
Supply (hereinafter referred to as “the Product”). Please read and follow the
Instructions strictly and keep it properly, to better understand the Instructions, well use
!the Product and avoid personal injuries or property losses
The Product is a cryogenic vessel. User is recommended to assign specific person to master
the Instructions and operate the Product as specified.
Organize safety education to relevant personnel regularly to avoid losses due to misoperation.
It is forbidden to overfill the Product. It should reach the lower edge of neck tube as the optimal
injection volume.
The pipeline connecting the liquid nitrogen container to the outside must be firm to prevent the
occurrence of liquid nitrogen leaking, dripping, splashing and other phenomena to ensure the
safety of the operator.
After use of the Self-pressurized Series tank, the inlet valve must be closed.
The bottom of the container is equipped with four high-strength casters, which is convenient for
short-distance movement of the container. When moving, care should be taken, and it must not
be pushed or moved violently to prevent collision. It is strictly forbidden to move on uneven
ground.
Transfer the Product with care to avoid overflow and splashing.
It is forbidden to contain any other low-temperature or high-temperature medium other than liquid
nitrogen; otherwise, quality warranty will expire!
Avoid skin exposure and take proper protection measures, such as low-temperature gloves and
goggles, while handling the Product due to its ultralow temperature (-195.8℃). Do not wear boots
to avoid cold injury when liquid nitrogen drops in the boots.
Do not touch the container opening of liquid nitrogen due to low temperature.
It is forbidden to block the container opening that has liquid nitrogen; otherwise, pressurization
and explosion may occur!
SAFETY PRECAUTIONS
WARNING
ATTENTION
Violation may lead to major casualties! Actions or operations which
must be prohibited
Actions or operations which
must be followed
Violation may lead to personal casualties,
container damage and property loss!

Avoid direct sunlight, but store the container at cool and ventilated place. Make sure to open the
doors and windows for ventilation during operation, to avoid suffocation due to oxygen deficit of
indoor space. Where necessary, an oxygen concentration monitor can be used.
It is forbidden to measure the liquid level of liquid nitrogen by using hollow tube; otherwise, cold
injury may occur! It is recommended to use professional tools and instruments for measurement.
It is forbidden to open the vacuum sealing joint that is designed for ensuring vacuum degree of
container interlayer; otherwise, the container interlayer may have vacuum deterioration.
It is forbidden to dismantle any part without permission! Welding on container surface is not
allowed!
It is forbidden to have tilting, horizontal or inverted placement, stacking or collision; handle it with
care and keep the container vertical.
For any cold injury due to liquid nitrogen, see a doctor immediately.
Observe the Product continuously during use. For any condensation or frosting on tank surface,
transfer away the sample immediately; otherwise, the sample can be damaged. We bear liability
for product loss only and not bear the liability of the third party.
The container mainly comprises a shell, a liner, swivel casters, drain pipes, various valves,
pressure gauges, vacuum sealing joints, etc. (see Fig. 1, Fig. 2 and Fig. 3):
For any quality issue, please return the Product to the Company for inspection and mainte-
nance, as the Product covers multiple professional techniques.
2. Schematic diagram of product structure
1. Product model formulation method
PRODUCT INTRODUCTION
54
Product type: K series products
Effective volume of the container (L)
The first letter of the Chinese Pinyin "Zi"
The first letter of the Chinese Pinyin "Dan"
The first letter of the Chinese Pinyin "Ye"
YDZ K
Safety valve Liquid inlet/outlet
valve
Liquid inlet/outlet
valve
Pressure
increasing valve
Float level meter
Pressure
increasing valve
Exhaust valve
Safety valve *
Exhaust valve
Safety valve
Manometer
Safety valve
Manometer
Fig. 1 Schematic Diagram of Valve (Regular Model) for Tank below 100L
Fig. 2 Schematic Diagram of Valve (Regular Model) For Tank above 100L
The quantity of YDZ-100Ksafety valves is one, and the quantity of YDZ-200Kand above safety
valves is two
*

When the inner container is filled with liquid nitrogen, the exhaust valve, the liquid inlet/outlet
valve and the pressure increasing valve are closed and the lock nut is tight. Under above
conditions, in case of no leakage, due to heat transfer from the container shell to the boosting
pipe, partial liquid nitrogen entering into the pipe will be vaporized due to heat absorption. When
the pressure increasing valve is opened, the vaporized nitrogen will enter into the space above
the liquid level of the liner through the valve immediately and meanwhile the liquid nitrogen in the
container liner will enter into the boosting pipe continuously for heat absorption and vaporization.
Since the volume of the vaporized nitrogen is over 600 times that of liquid nitrogen, a large
amount of nitrogen obtained after vaporization of a little liquid nitrogen will enter into the liner
through the opened pressure increasing valve continuously. As the nitrogen intake increases,
nitrogen accumulated in the space above the liquid level of the inner container starts to generate
a pressure on the inner container wall and the liquid level gradually. When the value of the
pressure gauge reaches 0.02MPa, the liquid inlet/outlet valve will be opened and liquid nitrogen
will be discharged through the drain pipe.
①Liner: It is used to fill liquid nitrogen.
②Locking nut: The seal of the liquid nitrogen filling port is threaded and equipped with a low
temperature resistant PTFE seal ring to prevent nitrogen leakage and pressure reduction.
③Exhaust valve: It shall carry out venting and pressure reduction based on needs. When the
screw plug at the liquid nitrogen filling port is unscrewed, first the exhaust valve must be opened
for venting and pressure relief. When the container is out of use, this valve shall not be opened.
④ Pressure increasing valve: When it is opened, the pressure of the liner will rise. When it is out
of use, it shall be closed tightly.
⑤Pressure gauge: It is used to indicate the pressure of the liner.
⑥Liquid inlet/outlet valve: It shall be connected with the liquid hose to fill liquid nitrogen into the
tank body or it shall be used as the makeup tank to fill liquid nitrogen into other container.
⑦Safety valve: The liner pressure shall be controlled below the maximum working pressure;
once the liner pressure exceeds the maximum working pressure, it will be opened automatically
to vent gas and release pressure. (The pressure shall not be too high frequently; otherwise it will
result in damages of the safety valve.)
⑧Vacuum sealing joint: It is the gas vent of the vacuum sandwich in the manufacturer of the
container, and it is an important part used to obtain vacuum; once the liner leaks and the
sandwich generates an internal pressure, it protects the liner and the shell from pressure release.
⑨Pressure maintaining valve: When the pressure in the container is lower than 0.07Mpa, the
pressure maintaining valve will be opened automatically for boosting. When the pressure in the
container is higher than 0.07Mpa, the pressure maintaining valve will be closed automatically to
stop boosting (configured for K series products).
3. Self-boosting Principle
4. Main Functions of Various Parts and Components
76
Fig. 3 Schematic Diagram of Valve (K series)
Fig. 3 Schematic Diagram of Valve (K series)
The quantity of YDZ-100K safety valves is one.
*
Pressure
maintaining valve
Digital display level
meter
Pressure
increasing valve
Liquid inlet/outlet
valve
Safety valve
Manometer
Exhaust valve
Safety valve *
Caster
Internal support
Liner
Thermal insulation layer
Adsorbent
Echaust port

5. Product Parameters
Please do not exceed the opening pressure of the safety valve frequently;
otherwise it will result in damages of the safety valve.
Model
5
329
510
15
19.1
40
0.15
2
0.05
0.09
0.099
0.15
Effective
capacity
（L）
Height
（MM）
Empty Weight
（kg）
Full weight
（kg）
Caliber
（MM）
Static
evaporation
(L/d)
LN2Output
（L/min）
Max. working
pressure
(MPa)
Standard working
pressure
(Mpa)
First stage safety
valve relief
pressure
(Mpa)
Pressure gauge
indicating range
(Mpa)
Second stage
safety valve
release pressure
(Mpa)
O.D
（MM）
15
404
750
23
35.3
40
0.38
2
0.05
0.09
0.099
0.15
YDZ-5 YDZ-15 YDZ-30 YDZ-50
YDZ-100K
YDZ-150
YDZ-200K
YDZ-300
/300K
YDZ-500
/500K
YDZ-240K
30
454
879
32
56.6
40
0.75
3
0.05
0.09
0.099
0.15
50
506
991
54
95
40
1
3
0.05
0.09
0.099
0.15
100
606
1185
75
157
40
1.3
4
0.05
0.09
0.099
0.15
0~0.25
150
706
1188
102
225
40
1.95
6
0.05
0.09
0.099
0.15
200
758
1265
130
296
40
2.4
8
0.05
0.09
0.099
0.15
240
758
1350
148
350
40
2.9
8
0.05
0.09
0.099
0.15
300
857
1459
202
448
40
3.3
8
0.05
0.09
0.099
0.15
500
1008
1576
255
665
40
5.5
10
0.05
0.09
0.099
0.15
The storage area for stainless steel liquid nitrogen biological containers shall have
sufficient space and shall be well-ventilated.
The temperature in the installation room shall be controlled at the normal temperature
level of 15°C-30°C.
The relative humidity in the installation room shall be controlled within the range of
40%-70%.
The indoor floor for placement of stainless steel liquid nitrogen biological containers
shall be flat.
The positions for placement of stainless steel liquid nitrogen biological containers
must be far away from the places with heat sources, combustibles, corrosion, intense
magnetic field, dust and serious oil stains.
①The vacuum sealing joints have been sealed before the products are delivered out of the
factory and protected by vacuum sealing joint hoods, and it is strictly prohibited to remove the
vacuum sealing joint hoods privately.
②The container is installed with a safety valve. The set pressure of the safety valve has been
adjusted before delivery out of the factory. The user shall not disassemble it in use. If it is
disassembled, the Company has the right and reason not to implement the three-guarantee
policy specified by the state any more.
③In order to make the indicated pressure of the pressure gauge accurate, the accuracy shall be
calibrated regularly. Meanwhile, the dial shall not be impacted by any external force, so as to
prevent deformations from causing errors of indicated values.
④The pressure increasing valve and the exhaust valve can control the internal pressure of the
container, and the liquid inlet/outlet valve can control the discharge flow of liquid nitrogen. In use,
the handle shall not close the valve excessively, so as to avoid damages; meanwhile, attention
shall be paid to the rotating direction of the valve handle; and the handle shall be rotated
anticlockwise to open the valve and shall be rotated clockwise to close the valve. When the
container is out of use for a long time, the pressure increasing valve must be closed and
meanwhile the exhaust valve must be opened.
⑤When the pressure gauge indicates a pressure reading, it is prohibited to unscrew the lock nut
or the liquid level meter at the top of the valve seat. First the exhaust valve shall be opened for
pressure relief. When no gas is discharged from the exhaust valve and the indicated value of the
pressure gauge is 0Mpa, the lock nut or the liquid level meter shall be unscrewed from the valve
seat;
1. Operating Environment Requirements
2. Precautions for Operation and Use of Products
Environmental
Requirements
PRODUCT USE
98
WARNING

⑥The locking nut at the top of the valve seat is a sealing part during boosting, and the thread is
very easy to freeze and difficult to screw after completion of drain. At this time, the method of
natural thawing or heating by an electric blower can be adopted for thawing before removal.
⑦The threaded hole of the locking nut shall be prevented from foreign matters. If the locking nut
is lost, the user shall contact our company to purchase a new one and shall not use any other
part to substitute it.
⑧In use, the bending radius of the drain metal hose shall not be too small; otherwise it may
result in leakage and breakage risks.
①Liquid nitrogen filling
Close all valves and connect the infusion pipeline of the drain valve. First the exhaust valves shall
be opened (all in open state) to reduce the pressure in the container and observe the pressure
gauge on the tank body. When the indicated value of the pressure gauge is 0 MPa, open the inlet
and drain valves (all open state) to fill liquid nitrogen. When a little liquid nitrogen ejects from the
exhaust valve, liquid nitrogen is fully filled into the tank body, the liquid inlet/outlet valve shall be
closed immediately and the exhaust valves shall be closed in turn;
Alternatively, use the pipe to fill liquid nitrogen into the container or use the liquid nitrogen
machine to fill liquid nitrogen into the container;
②Boosting
When liquid nitrogen is discharged, the liner pressure shall be increased. During boosting, the
exhaust valve and the liquid inlet/outlet valve shall be closed, the pressure increasing valve shall
be opened, and the indicated value of the pressure gauge shall be observed for gradual rise.
The maximum working pressure gauge value of the container is 0.09 MPa. However, in order to
minimize the liquid nitrogen losses, the pressure is generally increased to 0.05 MPa to meet the
drain needs. Under this value, the liquid nitrogen consumption is low and the use needs can be
met, so it is an economic use and operation mode.
When the pressure is increased to 0.02 MPa, liquid can be drained. When only a little liquid
nitrogen is needed, it is unnecessary to open the pressure increasing value; while when
continuous drain is needed, the pressure increasing valve shall be opened at the same time.
When the container is filled with liquid nitrogen, for the reason of safety, the
container shall not be fully filled and must be reserved with a certain gas-phase
space accounting for about 10% of the geometric volume of the container. The filling pressure of
the product shall not exceed 0.8MPa; otherwise it will cause irreversible damages to the safety
valve; when liquid nitrogen is stored in the container and it is required to convey liquid nitrogen,
all exhaust valves must be open.
3. Product Operation and Use
ATTENTION
After the pressure increasing valve is opened, usually the lower part of the shell is frosted, which
is the normal phenomenon when the container is working. When the container is fully filled with
liquid nitrogen (but a gas-phase space equal to 10% of the geometric volume of the container is
still reserved), the time required to increase the pressure to 0.05 MPa is about 20s; when the
liquid nitrogen storage is ¾, the time required to increase the pressure to 0.05 MPa is about
1min; and when the liquid nitrogen storage is ¼, the time required to increase the pressure to
0.05 MPa is about 8min. As the liquid nitrogen in the container is reduced, the time required to
increase the pressure will be increased.
③Drain
First the metal hose (supporting component) shall be screwed into the joint of the liquid inlet/out-
let valve, the exhaust valve shall be closed, and the pressure increasing valve shall be opened.
When the pressure of the inner container rises to the pressure gauge value of 0.05MPa, the liquid
inlet/outlet valve shall be opened and liquid nitrogen will be discharged; when the pressure gauge
value is 0.05MPa, it is an economic operating method; when the pressure gauge value of the
inner container is larger than 0.05MPa, liquid will be discharged and the discharge amount of
liquid nitrogen will increase accordingly.
④Pressure relief
After completion of discharge of liquid nitrogen, the pressure increasing valve and the liquid
inlet/outlet valve shall be closed, and then the exhaust valve shall be opened. If the container is
out of use for a long time, the pressure in the container shall be released.
⑤Container standing and storage
In order to prevent moist air from entering into the container, forming ice particles and blocking
the boosting pipe, the lock nut, the pressure increasing valve and the liquid inlet/outlet valve can
be closed and a small part of the exhaust valve shall be opened to prevent the pressure in the
container from being too high and causing frequent jumping of the safety valve.
⑥ Handling of drain container
Ⅰ. Indoor movement. The container is equipped with four high-strength swivel casters for
convenient indoor movement. Since the product belongs to a high vacuum container, the
movement shall be as slow as possible, so as to avoid impact or collision; otherwise, it will not
only cause depression of the container shell and performance degradation, but also cause
damages of the internal structure of the container, so special attention shall be paid to movement
of the container.
Ⅱ. Lifting. The product belongs to a high vacuum container. Before lifting, the wire rope shall be
sleeved on the hand ring; during lifting, the wire rope shall be vertical and stable and shall not be
pulled hard, placed hard or lifted obliquely.
1110

①The daily evaporation rate of the product is tested by the weighing method.
②Test environment conditions:
a. The test environment shall be clean and well-ventilated and taken with anti-static and fireproof
measures;
b. The test site shall be set up with warning areas and red signal signs;
c. The test site shall be prevented from strong electromagnetic interference and strong vibration
and impact;
d. The ambient pressure is the local atmospheric pressure, the temperature range is 0°C~40°C,
and the relative humidity is lower than 85%;
③The daily evaporation rate α of the product is calculated according to the following formula:
Wherein, -- daily evaporation rate, in percent per day (%/d);
——evaporated gas mass within 24h, in kilogram per day (Kg/d);
——density of saturated liquid nitrogen under standard atmospheric pressure, in kilogram per
cubic meter (kg/m³);
——effective volume of the tested part, in cubic meter (m³).
During operation and use of the product, the open/closed state of each valve is shown in Table 1:
Valve Name
Operation and Use Liquid Inlet/
Outlet Valve
Open
Close
Open
Close
Close
Close
Close
Open
Close
Close
Open
Open
Open
Close
Close
Open
Open
Close
Close
Close
Close
Exhaust Valve Pressure Increasing Valve
Liquid nitrogen filling
Intensification
Fluid discharge
Pressure release
Container standing and storage
Medium and long distance transport
No liquid nitrogen is stored.
4. Test and Calculation Method of Daily Evaporation Rate of Product
Note: The daily evaporation rate of the product shall be tested according to GB/T 18443.5-2010.
When the ambient temperature and the atmospheric pressure are not tested according to the
above regulations or the minimum division value of the measuring instrument is different from the
standard requirement, there may be a deviation between the calculated value and the actual daily
evaporation rate of the product.
The float level meter is a direct reading level meter manufactured according to the force balance
principle. The liquid level changes in the sealed container can be directly indicated and
determined by observing the indicator ring sign or the pointer in the transparent display. The
structure is simple and reliable, the indication is flexible and conspicuous, and the visual reading
is convenient and accurate.
①Sleeve the PTFE flat seal gasket into the float level meter, then wrap M18 with Teflon tape,
connect the thread at the top of the tank body and screw into the container;
②The following diagram is the schematic diagram of installation of the float level meter;
①Measuring method: visual inspection
②Ambient temperature: -40~+60°C
③ Measuring range: 0~1200mm
④Explosion prevention: safety type explosion prevention
1. Product Overview:
2. Technical Performance Parameters
3. Installation
Base
Tank
Measuring rod
INTRODUCTION AND USE OF LEVEL METER
FLOAT LEVEL METER
1312

4. Schematic Diagram of Structure of Float Level Meter
DLZ-300 DIGITAL DISPLAY LEVEL METER (K SERIES)
1. Product Overview
The DLZ-300 digital display level meter developed by our company doesn't need any external
power, and the built-in lithium battery can supply power for more than three years. It is applicable
to accurate continuous level measurement of liquid nitrogen stored in 0-0.6MPa low-temperature
container and it has the incomparable technical performance. The data of the digital display level
meter can be collected and uploaded by radio to 800N and uploaded to MRC big data cloud
platform via GPRS or WiFI. It has the advantages such as simple use, wide applicability, high
intelligence, stable measurement without drift, high stability, high reliability, tight and waterproof
structure and not requiring regular maintenance and recalibration.
Display unit
Base
Extension spring
Upper ring connecting rod
Lower ring connecting rod
Measuring rod
①Power supply: 3.6V lithium battery power supply, average working current: about 15uA
②Effective liquid level measuring range of sensor: 200mm-1000mm
③ Diameter of sensor rod: Φ12mm
④Operating humidity range: relative humidity: 0~80%
⑤ Measuring accuracy: ±1%
⑥ Working pressure: 0-0.6MPa
⑦ Measuring medium: liquid nitrogen
①Sleeve the PTFE flat seal gasket into the sensor and then wrap M18 connecting thread with
Teflon tape and screw it into the container.
②In installation and use of the sensor, if dust, scrap iron, water and other foreign matters enter
into the inner and outer stages of the sensor, they will influence the normal work of the sensor.
③ There is cabling in the sensor and the level meter shall not be disassembled or assembled
privately.
④Fig. 1 is the schematic diagram of structure of DLZ-300 digital display level meter, and Fig. 2 is
the schematic diagram of installation of DLZ-300 digital display level meter;
2. Technical Performance Parameters
3. Installation and Instructions
Fig. 1
M18X2
60
58
M18X/M22X1.5
Effective measuring area
Effective measuring area
1514

Note: The digital display level meter is set up with a timing long press setting key. When the
following letter is displayed, release the setting button and then enter into the corresponding
setting state. After one item is set, wait for 10s to complete the setting!
①Long press S to display and then release the key: It indicates and displays the
capacitance value measured by the current sensor.
②Long press S to display and then release the key: Enter the correct password and wait
for 10s to set the parameter. If the password is wrong, wait for 2min to enter a new password.
The default initial password is 0, and the password setting can be modified.
After entering the correct password, return to the home interface and long press S key again to
enter the setting interface.
③Long press S to display : Setting is not required. Settable range: 0-990mm.
④Long press S to display : Setting is not required and the unit is mm.
4. Settings of DLZ-300 Digital Display Level Meter
Base
Tank
Measuring rod
⑤Long press S to display : It indicates setting the measuring range of the current sensor.
That is to say, the above diagram displays the distance between two holes of the level meter;
settable range: 0-999mm.
⑥Long press S to display : The communication address is set. Settable range: 0-255 min
(the communication address with 800N is set. When it is consistent with 800N address, DLZ-300
liquid level data can be transmitted by radio to 800N).
⑦Long press S to display : It indicates setting the new password of the current level meter.
⑧Long press S to display : It indicates setting the capacitor value when the current level
meter doesn't contact liquid nitrogen.
⑨Long press S to display : It indicates setting the capacitance value when the test range
length of the current level meter (the upper hole of the level meter) is completely soaked in liquid
nitrogen.
Alarm and faults of liquid level detection alarm:
①Display EOL: It indicates disconnection between the sensor and the transmitter.
②Display EIH: It indicates short circuit of inner and outer stages of the sensor and
MAINTENANCE AND SERVICING
Note: All parameters have been set when the level meter is delivered out of the factory and the
user is not required to set the parameters.
In long-term use of the container, the liner will accumulate wet air slowly and the moisture in the
wet air will form tiny ice grains at a low temperature. If these tiny ice grains are attached to the
pipe wall, they will block the boosting pipe and the drain pipe. If the corresponding ice melting
measures are not taken at this time, the following adverse consequences will be caused:
①Boosting is very slow or completely impossible;
②Although there is an internal pressure, liquid nitrogen is drained slowly or not drained.
In order to extend the interval of ice melting, attention must be paid to the following items:
①In the liquid filling process, the liquid filling time shall be minimized to reduce the accumulation
of the wet air entering into the container;
②When there is no liquid nitrogen stored in the container, all valves must be closed to prevent
wet air from entering into the container.
1. Technical Operation of Ice Melting and Thawing
1716

4. Regularly check and regularly calibrate the safety valve. When the pressure in the tank body is
higher than 0.1MPa, check whether the safety valve jumps normally;
5. Regularly observe whether the locking nut is tight. If not, use a wrench to screw it tightly and
then re-observe whether it is tight. If the locking nut is still untight after it is screwed, replace the
seal gasket and then screw it;
COMMON PROBLEMS
The handles of the pressure
increasing valve, the exhaust
valve and the liquid
inlet/outlet valve are too
tight.
The connection between
the liquid inlet/outlet valve
or the exhaust valve and
the valve seat leaks.
The boosting time is long
or boosting is completely
impossible.
Although there is an internal
pressure, the drain rate is
slow or it is completely
impossible to drain liquid.
The internal pressure of the
container has reached
above 0.09MPa for once.
The safety valve is still not
opened.
After the safety valve is
opened, the pressure in the
container drops to below
the set pressure, the spring
can't be reset and the valve
continues to eject gas.
1. The safety valve is frozen;
2. The set pressure of the
safety valve is offset.
1. The safety valve is frozen;
2. There are foreign matters
on the sealing surface of
the safety valve;
3. The set pressure of the
safety valve is offset.
1. Conduct ice melting and water
removal;
2. Remove the foreign matters on
the sealing surface;
3. Return to depot
1. Conduct ice melting and water
removal;
2. Remove the foreign matters on
the sealing surface;
3. Return to depot
1. The drain pipe or the
drain valve is frozen;
2. There is no liquid nitrogen
in the container or not all
liquid inlet/outlet valves are
opened.
1. Carry out ice melting and water
removal.
2. Open all liquid inlet/outlet
valves.
1. The boosting pipe or the
pressure increasing valve is
frozen;
2. Air leaks.
3. The safety valve cannot
return normally after
jumping and it causes air
leakage;
4. There is no liquid
nitrogen in the container or
there is a little liquid
nitrogen in the container;
1. Conduct ice melting and water
removal;
2. Mix soap with water, check the
suspected air leakage part and
eliminate leakage.
3. Check whether the safety valve
can jump and return normally.
4. Check the capacity of liquid
nitrogen in the container.
The connection between
the valve stem and the
valve body leaks, and the
gasket or the sealing
material is damaged.
Replace the PTFE seal ring at the
connection or the thread sealing
material.
In use, use an electric blower to
heat the valve as the temporary
measures. After liquid nitrogen
in the container is emptied,
disassemble the valve to
remove moisture or ice.
There is moisture or ice in
the valves.
1
2
3
S/N Fault Reason Troubleshooting Method
4
5
6
Once the boosting pipe is blocked by ice and can't increase the pressure, the following ice
melting measures can be taken:
①Adopt the air pressure method to eliminate the residual liquid nitrogen in the container. The
method is as follows: Screw the lock nut at the top of the valve seat tightly, close the pressure
increasing valve, open the liquid inlet/outlet valve and the exhaust valve, and use nitrogen or dry
gas (do not use oxygen or any other combustible gas) to increase the pressure from the exhaust
valve to the container, so as to empty the residual liquid nitrogen in the container via the liquid
inlet/outlet valve. If it is found that the liquid inlet/outlet valve is blocked, remove the liquid
inlet/outlet valve, and observe the valve seat screw hole corner and the liquid inlet/outlet valve
body for blockage of ice particles. In case of blockage, use hard wires to remove ice particles or
use an electric blower or a hot blast dryer for ice melting (at a temperature not higher than 40°C)
and then liquid drainage.
②Under the condition of emptying the residual liquid nitrogen in the container, close the liquid
inlet/outlet valve, remove the external connecting pipe of the pressure increasing valve, and
continuously fill the hot air at normal temperature or at a temperature not higher than 40°C and at
a pressure of about 0.05MPa from the exhaust valve for several hours. When it is observed that
the gas without beads ejected from Place A increases gradually, it indicates that the boosting pipe
is smooth and the ice melting and water removal work is completed.
Note: Since the humidity at each place, the use frequency of the container and the liquid nitrogen
filling method are different, the interval of the ice melting measures can be decided by the user
according to the circumstances.
①Liquid level ruler estimation method. In use, insert the liquid level ruler into the container until
the liquid level ruler contacts the bottom of the liner, stand for 15s and then take out the liquid
level ruler to expose it to the air. Since the part soaked by liquid nitrogen above the liquid level
ruler will form a layer of white frost in the air, roughly estimate the liquid nitrogen storage from the
boundary of the white frost.
②Weighing method. Use a weighing machine to measure the mass of the container filled with
liquid nitrogen, subtracted by the empty weight of the container in Table 1 of the Instructions to
obtain the mass of liquid nitrogen in the container, and thereby calculate the volume of liquid
nitrogen (the density of liquid nitrogen is about 0.808 kg/L). The accuracy of this method is higher
than that of the liquid level ruler estimation method.
3. Regularly check and regularly calibrate the pressure gauge, observe the indicated readings for
abnormalities, and observe whether the reading of the pressure gauge is zero when there is no
liquid nitrogen and no pressure in the tank body;
2. Measuring Method for Liquid Nitrogen Amount in the Liner
1918

PACKING LIST
Including locking nuts*
Standard configuration above 100L (included)
Standard
Standard
One piece is equipped and one piece is standby
*
Set
Set
Pc.
Pc.
Pcs.
Set
Set
Pc.
Pc.
Pcs.
1
1
1
1
2
Main tank body
Float level meter
Single-layer infusion hose
Product Instructions
PTFE sealing gasket
Main tank body
Digital display level meter
Single-layer infusion hose
Product Instructions
PTFE sealing gasket
Item Type
Item Type
Regular Model
Qty.
Qty.
Unit
Unit
Remarks
Remarks
Including locking nuts and pressure stabilizers
Standard
Standard
Standard
One piece is equipped and one piece is standby
1
1
1
1
2
K Series Products
YDZ-5/15/30/50 are equipped with lock nuts, while the regular models
YDZ-100K/150/200K/240/300/500 are equipped with float level meters and not equipped
with lock nuts any more
20
Hagavish st. Israel 58817 Tel: [phone], Fax: [phone] ,3
[email protected]
MRC. 8.22