Mixers and agitators give a personal matter for mechanical seals because some mixers or agitators are accelerated on top or on the side of a vessel the long shaft being used to meld or agitate has an effect with running out. The longer the shaft the larger the runout.

Overview of Mixer Seals

Why Mixer and Agitator Seals?

Mixer and agitator seals are comparable to pump seals with one major exception, they are noted prone to shaft runout. The reason is the typically long shaft elongation that offers the shaft leverage against bearings and seals. One result is to accelerate the seal faces in a fashion the allow run out. Type 19 seal is personal in the dual seal rotary seal faces fun next to each other against a single station. This a very personal design that allows for more runout than traditional single cartridge or double cartridge seals. If the shaft is short or very well supported by numerous bearings restricting runout, a type 19 may not be compulsory.

Another effect with the agitators and mixer seals is they frequently do not admit lubrication. In the right conditions, a mechanical seal can operate dry but other important issues have to be considered

The heat generated by the seal faces? The shaft speed and the materials of the erection of the mechanical seal are even greater significance than a flushed/lubricated seal. The best connection of seal faces is carbon Vs. Silicon carbide due to low friction generated between these two faces. Glass filled PTFFE faces are another capability result.

Chemical congruent of the product being sealed must, of course, be calculated

If conventional double seal with environmental govern are utilized caution must be taken to be implicit enough lubrication is given without contamination of the product being mixed.

Mixer and agitators seals

Mixer seal style 19 features

• Can withstand extravagant shaft runout;
• Stationary seal face and spring design decease vibration and harmonic issues;
• Preassembled, preset double cartridge seal for simple installation;
• No bottom stuffing box requirements;
• Pressures tested at the factory before shipment;
• Non-fretting static 0-ring eliminates shaft wear;
• Closed-loop flush system prevents contamination of product;

The determination if a seal like a type 19 mixer seal required depends on many factors. You must consider the run out of course which should be measured with a dial indicator. If the runout is greater than 0.005" a seal designed for higher run out should be considered.

Mixer applications are similar to process pump applications, there are only few differences:

• Dual seals are generally required because the seal is often located above the fluid resulting in the dryness of a single seal.
• Many mixers run under vacuum conditions depending use of balanced seals.
• Minimum entering designs generally have a lot of solid in the seal area.
• Advantage of mixer seals

Mixer seals are specially designed for mixer, agitators and reactor applications, to combat the ineligible radial or axial shaft motion that occurs in this application. Mixer seals can be configured to run wet, dry or with a gas barrier.