Chemical pumps are
widely used in chemical, petroleum, metallurgy, light industry, synthetic fiber,
environmental protection, food, medicine and other sectors. Compared with other
types of pumps, chemical pumps have the advantages of stable and reliable
performance, good sealing performance, beautiful appearance, convenient use and
maintenance, etc. It plays a great role in improving product quality, reducing
leakage, emission, dripping and leakage, preventing pollution and improving the
environment. What are the main sealing forms of chemical pumps?
1. Oil
seal:
It is a self tightening lip seal with simple structure, small size, low
cost, convenient maintenance and small resistance torque. It can not only
prevent medium leakage, but also prevent external dust and other harmful
substances from invading. It also has a certain compensation ability for wear,
but it is not resistant to high pressure. It is generally used in chemical pumps
in low-pressure occasions.
2. Gasket seal:
The gasket is the basic element
of the static seal of centrifugal pump, which is widely used. The selection of
gaskets is mainly determined by the factors such as the medium conveyed by the
chemical pump, temperature, pressure and corrosivity.
3. Thread
seal:
Generally, there are two types of chemical pumps, one is screw
connection gasket seal, and the other is thread plus filling seal, both of which
are used for small diameter thread connection sealing occasions. The sealing
element of the gasket seal of the threaded electric diaphragm pump is the
gasket, and the thread only provides the compression force.
4. Labyrinth
seal:
When the design is reasonable, the processing is excellent, the
assembly is complete, and the speed is high, the labyrinth seal effect is good.
However, in practical applications, there are many chemical pump leaks, so they
are not commonly used in chemical pump seals.
5. Packing seal:
It is to
put the packing with compressibility and resilience into the stuffing box, and
convert the axial compression force of the gland into the radial sealing force,
so as to play a sealing role.
This sealing method is called packing seal, and
this packing is called sealing packing. The packing seal is widely used in the
design of chemical pumps because of its simple structure, convenient
replacement, low price, and wide adaptability to speed, pressure and
medium.
6. Power seal:
When the chemical pump is running with, the
pressure head generated by the auxiliary impeller balances the high-pressure
liquid at the outlet of the main impeller, thus realizing the sealing. The
auxiliary impeller does not work during shutdown, so the shutdown sealing device
must be equipped at the same time to solve the possible leakage of chemical pump
during shutdown.
The auxiliary impeller seal is simple in structure, reliable
in sealing and long in service life. The chemical pump can achieve no leakage
during operation, so it is often used in the chemical pump to transport media
containing impurities.
No comments:
Post a Comment