Pump dry gas seal technology and application

First, an overview of dry gas seal

Dry gas seal is a new type of non-contact seal developed from the foundation of gas dynamic pressure bearings in the late 1960s. The seal utilizes the principle of fluid dynamics to realize the non-contact operation of the sealing end surface by providing the dynamic pressure groove on the sealing end surface. After years of research, the British company John Crane took the lead in the late seventies to apply dry gas seals to gas delivery equipment on offshore platforms and achieved success. Dry gas seal was originally developed to solve the shaft seal problem of high-speed centrifugal compressors. Due to the non-contact operation of the seal, the friction material of the seal is basically not limited by the PV value and is particularly suitable as a shaft seal for high-speed and high-pressure equipment. With the increasingly mature dry gas sealing technology, its application is also more and more broad, at present, dry gas seal is gradually being applied in centrifugal pumps and blenders. In short, where the use of mechanical seals can be used dry gas seal occasions. Compared with the mechanical seal, dry gas seal has the following advantages:
1, long sealing life, stable and reliable operation;

2, the sealing power consumption is small, only about 5% of the contact mechanical seal;

3, compared with other non-contact seals, dry gas seal gas leakage is small;

4, can achieve zero escape of the medium, is an environmentally friendly seal;

5, seal auxiliary system is simple, reliable, use does not require maintenance;

Second, the centrifugal pump with dry gas seal

Centrifugal pump transport medium is liquid. According to different working conditions, the following types of seals can be used:

1, double-sided dry gas seal

Double-sided dry gas seal can be used in the vast majority of centrifugal pump shaft seal, it has the following characteristics:

1) Replace the traditional "liquid blockage" principle with "gas blockage", that is, replace the pressured sealing liquid with pressurized sealing gas to ensure "zero escape" of the process medium;

2) The entire seal non-contact operation, the power consumption is only 5% of the traditional double-sided seal, the service life of more than 5 times longer than the traditional seal;

3) A simple auxiliary system to ensure that the process medium is not contaminated and the process medium does not leak to the atmosphere, completely get rid of the traditional dual-end mechanical seal on the oil system. Sealed gas using industrial nitrogen or industrial instrumentation, the pressure is higher than the medium 0.15-0.2MPa.

Pump double-sided dry gas seal is inadequate is:

1) gas source that requires a certain pressure, gas pressure at least higher than the medium pressure 0.2MPa;

2) a trace of gas into the process.

2, series dry gas seal

Pump series dry gas seal has the following characteristics:

1) dry gas seal and contact type mechanical seal used in tandem, the mechanical seal is the main seal, the dry gas seal is the secondary seal;

2) Dry gas seal and the main seal between the access to nitrogen, to ensure that the main seal has a certain back pressure, greatly extending the life of the main seal;

3) Leakage of the main seal of the process medium with sealing gas into the torch to ensure that the process medium does not leak to the atmosphere, is an environmentally friendly seal;

4) After the failure of the main seal, the dry gas seal plays a main role of sealing for a short period of time to prevent a large amount of leakage of the process medium to the atmosphere.

5) The life of this type of seal depends on the service life of the mechanical seal, which is usually about 2-3 years.

6) The seal is mainly used for volatile media occasions, such as liquid hydrocarbon media; less demanding on the seal gas pressure.

The inadequacies of the seal are:

1) The seal is not yet a perfect dry gas seal, its overall performance is between the mechanical seal and dry gas seal.

2) The seal is suitable for volatile media occasions, the use of a narrow range.

1. Concrete Spun Pile Mould:

Concrete Spun Pile Mould is a kind of Steel Mould, it is mainly apply to Concrete Spun Pile Plant to produce the Centrifugal Reinforced Technology (PHC ) Concrete Spun Pile, In order to meet customer's requirement to produce high strength PHC concrete pile, Jiangsu Haiheng Company have long term cooperation relationship with Japan spun pile factories for improve the design and technology of mould and use advanced processing equipment, HH's Spun Pile Mould has got the leader market share in the countries like Japan, Vietnam, Indonesia, Malaysia, Thailand, Myanmar, Cambodia etc.


Our Mould Advantages:

1. Mould's tongue-and-groove is designed by the dislocation of upper and lower shell boards, matchboard is plane surface. Slurry does not leak and it is easy to clean mould.

Centrigual Reinforced Spun Pile Mould

2. The tyre is "T" type forgings. Tyre and its support plate are as whole.

3. Self-developed six-meter press machine of mould inside shell. The inside shell seam extends from two meters to six meters, to minimize welds and mould strength and improve the external appearance of the products

6meter Moulding Machine


4. Welding process uses CO2 arc shield weld which makes its appearance simple and weld seam neat. Our company cooperated with colleges to introduce [robot welding project".

5. Long lathe, manufacture the whole set mould under fifteen-meter length, greatly increases concentricity of the tyre and flange.


Spun pile Mould Specification:

Inside diameter(mm)

Wheel base(mm)

 Wheel Diameter(mm)







































 If you have any questions, please contact with us directly. Concrete Pile Moulds are produced by High Quality and Esay transportation, quick assembling, good rigidity and smooth working. Welcome you can visit our Factory.For inqury,Please send mail directly to us.

Concrete Spun Pile Mould

Concrete Spun Pile,Reinforced Concrete Spun Pile Mould,Phc Spun Pile Mould,Pretensioned Concrete Spun Pile Mould

Jiangsu Haiheng Building-Materials Machinery Co.,Ltd , https://www.jshaiheng.com