①
The daily evaporation rate of the product is tested by the weighing method.
②
Test 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%;
③
The 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.
①
Sleeve 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;
②
The following diagram is the schematic diagram of installation of the float level meter;
①
Measuring method: visual inspection
②
Ambient temperature: -40~+60°C
③
Measuring range: 0~1200mm
④
Explosion 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
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