Choosing the right split cartridge mechanical seal

Split seals are an innovative sealing solution for environments where it may be difficult to install or replace conventional mechanical seals, such as hard to access equipment. They are also ideal for minimising costly downtime for assets critical to production by overcoming the assembly and disassembly difficulties associated with rotating equipment. Several semi and fully split mechanical seals have been designed by various manufacturers, however, with so many options available on the market how do you know what is really the best choice for your application?

Challenges

While many designs may achieve the goal of reducing the amount of time required to change out a mechanical seal, they have introduced other issues. These inherent design problems can be attributed to a few factors:

• Some component-style split seal designs have several loose parts which must be handled with extreme care

• Installation may require precise measurements or the use of various shims or special tooling to accurately align and set the mechanical seal assembly on the rotating shaft

• Some seals utilise an internal clamping method, limiting the torsional and axial holding power to positively locate the seal on the equipment

Another potential concern arises when the shaft position must be adjusted after the seal has been set. In certain designs, the set screws lock the rotary seal ring assembly to the shaft and cannot be reached after the two stationary gland assemblies have been bolted together.

This means total disassembly of the seal once it has been installed, leaving the end user responsible for verifying that a complicated seal with precision lapped faces is correctly reassembled on the pump.

Flexaseal solution

Flexaseal addresses these disadvantages and limitations with the Style 85 two-piece split cartridge mechanical seal assembly. The Style 85 split seal consists of only two unitised, self-contained assemblies which fit together over a shaft to form a self-setting and self-aligning cartridge seal design.

This fully split cartridge mechanical seal design eliminates the handling of a lot of loose, delicate, precision manufactured components
and allows for a very simple, easy and time-saving installation with no measurements or guesswork. The critical primary sealing faces are held together and safely contained within the two split gland and sleeve assemblies, well protected from any mishandling, dirt or contaminants.

Advantages

• The easiest installation of any split seal in the world: simply attach the two cartridge halves over the shaft and mount to the pump like any other cartridge seal

• The first split cartridge mechanical seal in the world in which just two pieces are handled: the lapped faces are secured safely in cartridge halves and cannot be cocked or chipped

• Only split cartridge mechanical seal in which the impeller can be adjusted without removing the seal: simply reinstall setting clips, release set screws and adjust impeller position then re-tighten set screws and remove the clips

• Only split cartridge mechanical seal that is fully assembled, and pressure tested at the factory: sealing integrity is confirmed before being sent to the field, thereby ensuring a high success rate for each installation

• No measurements, no shims, no special tools, and no glue: cartridge setting clips assures proper axial and radial alignment to make installation even easier

The design of the Style 85 is like no other on the market. While most split mechanical seals are mounted outside the stuffing box and are designed to function like an outside seal, the Style 85 was engineered as a true, fully split cartridge mechanical seal. It is a hydraulically balanced, stationary multi-spring design that is primarily mounted outside the stuffing box.

These features allow the centrifugal force to keep the solids away from the seal faces while maintaining the ability to handle higher speeds, internal pressures and misalignment. No need to worry about solids, as the springs are protected and out of the product to eliminate clogging.

The static shaft sleeve “o” ring is positioned outside of the stuffing box to assure a good sealing surface, even on worn packing sleeves. The Flexaseal Style 85 Split Cartridge Mechanical Seal… Fast, Simple and Reliable!

This Sponsored Editorial is brought to you by IndustriTech. For more information contact the Australian distributor at [email protected] or visit www.industritech.com.au.

Find Seals Related Companies In The Pump Industry Capability Guide

John Crane

Sykes Group Pty Ltd

Assett Mechanical Engineering

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