Advantages of the YOKOTA Non-External-Flushing Mechanical Seal

Reduction of equipment costs

Piping for external sealing water and electrical instrumentation are not required.

Reduction of running costs

The sealing water cost is not required. (For example, you can save 0.3 litre minute of water which amounts to as much as 150 tons a year.)

The cost for maintaining sealing water in the case of a double mechanical seal or the cost for adjusting leakage in the case of gland packing is eliminated.

Power consumption can be reduced because of the low friction on the sliding surface.

The water imbalance in a plant process due to mixture of sealing water into pumping water can be prevented, and treatment of leaked sealing water is not required.

A comparison of running costs

The cumulative totals of running costs for continuous operation of pumps with a shaft diameter of 48mm and a 30kW motor equipped with a Non-External-Flushing Mechanical Seal, double mechanical seal, or gland packing, are as shown below:

Features

Stable seal performance for a variety of purposes because of the stationary balance type structure.

Easy installation without remodeling a pump casing even when installing to a pump that previously used gland packing.

Malfunctions due to adhesion of slurry, corrosion, or abrasion are not possible because the pins and springs do not contact liquids.

Due to the self-alignment mechanism between its loose ring and rotary ring, the sliding surface of the loose ring floats and efficiently follows the sliding surface of the rotary ring.

Excellent wear resistance to high density slurry liquid because the SiC of the sliding surface has excellent hardness, sliding performance, and corrosion resistance.

YST130N is used for the parts that contact liquids. This is the duplex type stainless steel YOKOTA has developed, and can be used for various liquids because of its remarkable corrosion resistance, wear resistance, and mechanical strength.
(For details of YST130N, please refer to this page.)

Supply of sealing water, such as industrial water, from the outside is not required.
(Please use self-flushing method in order to prevent sliding parts from possible dry-operation caused by a cavity generated within the stuffing box due to generation of negative pressure in the case of self-priming operation, or mixture of air in the case of force pumping operation.)

Performance

As you can see, there are no problems despite slurry adhesion.

Applications

The YOKOTA Non-External-Flushing Mechanical Seal can be used for almost all kinds of liquid. It proves excellent performance especially when used in pumps dealing with the following liquids:

Electricity:

Smoke discharging desulfurizer, Seawater drawing, Waste water treatment, other

Electronics:

Ultra-pure water production, Waste liquid treatment, other

Chemical:

Acid liquid, Alkaline liquid, Solvent, other

Sewage:

Polluted water, Sludge, Liquid containing earth and sand

Others:

Seawater, Condensed seawater, Liquid containing slurry, other

There is detailed information about applications to seawater-related facilities. Please refer to "Current Topics: Aquarium".

∗ is shown in the table of dimensions.

We can also manufacture seals with dimensions other than those listed above.

We can also manufacture cartridge type seals upon request.

The above combinations of materials are standard. We can also manufacture these seals using other materials upon request.

Please use self-flushing method in order to prevent sliding parts from possible dry-operation caused by a cavity generated within the stuffing box due to generation of negative pressure in the case of self-priming operation, or mixture of air in the case of force pumping operation.