The quest for leak-free chemical pumps has always been a top priority in the field of chemical equipment. This demand has significantly boosted the growing popularity of magnetic pumps and canned motor pumps. However, despite these advancements, achieving complete zero-leak performance remains a challenge. Issues such as the lifespan of the magnetic pump's isolation sleeve and the canned motor pump's shielding sleeve, material corrosion, and the reliability of static seals continue to require further attention. Below is a brief overview of some fundamental aspects of sealing technology:
1. Static Seals: In terms of static sealing, there are primarily two forms—O-rings being the most commonly used. The viscosity of the conveyed medium plays a crucial role in the pump’s performance. As viscosity increases, the pump’s head decreases, leading to reduced optimal flow rates and head, while power consumption rises, ultimately diminishing overall efficiency. Specifications provided in catalogs are typically based on water transport and may need adjustment when dealing with viscous media. For handling highly viscous fluids like pulp, pastes, or other thick liquids, a screw pump is often recommended.
2. Sealing Materials: Static seals in chemical pumps generally utilize fluorine rubber, with PTFE material reserved for special cases. For the mechanical seal rings, selecting the appropriate static material is vital. While tungsten carbide offers excellent durability, its high cost and unreasonable hardness differences compared to other materials make it less ideal for certain applications. It’s best to match the sealing material to the specific medium properties.
For dynamic sealing, chemical pumps rarely use packing seals; instead, mechanical seals are predominantly employed. Mechanical seals come in various types such as single-ended and double-ended, balanced and unbalanced. Balanced seals are better suited for high-pressure environments (typically pressures above 1.0 MPa). Double-end mechanical seals are particularly useful for applications involving high temperatures, crystallization-prone media, viscous substances, particle-containing fluids, and those with toxic or volatile components. These double-seal systems often require an isolation fluid injected into the sealed chamber, with the pressure typically set 0.07 to 0.1 MPa higher than that of the medium.
Despite these advancements, continuous research and innovation are essential to address lingering challenges and improve the reliability and longevity of chemical pump sealing technologies.
Chemical Industry Mass Flow Meter
Sealand is a professional supplier of Chemical Mass Flow Meter, Chemical Mass Flowmeter, Chemical Flowmeter, Chemical Flow Meter, Chemical Coriolis Meter, ATEX, IECEx & CE approved.
The meter can work with a pulse receiver(Count). The connection is as follows. The
resistance value is up to the cable length & the max. input pulse frequency of receiver.
Current 10mA is suitable for most receivers; however, you can reduce the resistance value
when the cable is long. The max. current could be 50mA. Please use the fixed frequency
output function to check if the cable length & resistance value is suitable.
Please check following items before operation, and operate according to relevant rules.
a) If the meter is damaged during shipment and installation;
b) If the voltage is same as marked on nameplate;
c) If the fuse is correct;
d) If the meter is grounded properly.
e) If the Meter SN on the nameplate of sensor and transmitter are the same.
If everything is fine, please open all valves, make the pipeline full of liquid and then power on
the meter for warm-up for 20min before operation. Finally, conduct zero calibration after first
start, and shall do it again if the meter is moved to another site.
Preparation for zero calibration:
a) Power on the meter for approximately 20min for warm-up;
b) Run the process fluid through the sensor until the sensor temperature reaches the normal
process operating temperature.
c) Close the shutoff valve downstream from the sensor.
d) Ensure that the sensor is filled with fluid and the process flow has completely stopped.
Chemical Mass Flow Meter, Chemical Mass Flowmeter, Chemical Flowmeter, Chemical Flow Meter, Chemical Coriolis Meter
Zhejiang Sealand Technology Co., Ltd. , https://www.sealandflowmeter.com