Generic selectors
Exact matches only
Search in title
Search in content
Post Type Selectors

New Technology Answers to old Sealing Problems

Industry Topics
Picture of two bearing isolator seals

New Technology Answers to old Sealing Problems

Seal failures are a way of life to the mechanical world. There are vast reasons why seals fail. There are many types of seals in the market place. My focus with this article is why I would select a bearing isolator over a rotating lip seal.

First things first, if we are assuming installation are correct, why are the lip seals failing? Generally speaking the lip seals fail due to; hardening, scarring, swelling, cracking, or grooving. What causes these failures? Insufficient lubrication, heat, contaminants, or movement are some of the causes but not all. You will want to select bearing isolators that are made out of blended materials consisting of a PTFE. This will handle chemicals, temperature, and fluid absorption enabling seals to run dry. Second, you want a design that handles movement and is bi- directional. Third, select a two piece seal that is unitized thus enabling the seal to rotate with the shaft preventing grooving of the shaft. These above components when combined will address your sealing concerns.

In choosing bearing isolators you first need to know if the system needs to breathe or be hermetically sealed. The answers to the two questions will determine the flow chart in selecting the isolator. With the breathable seal you have a non-contacting design with virtually no torque consumption. Also, this will not cause wear on the shaft. The breathable seal design has fewer components and offers ease of installation. This design is the seal of choice when axial movement is a concern. Unlike lip seals, when speed and lack of lubrication are an issue, this design is the solution to embrace. When application requires the system to be totally enclosed or is sensitive to atmospheric surroundings you should be using a contacting seal. This design will enable you to close loop within the system. You may want to choose a check valve breathing system (desiccant filter) along with contacting bearing isolators. These total packages enable the moisture to be pulled from the system and do not allow atmospheric conditions to attack the internal mechanics.

When selecting a contacting bearing isolator you need to select a material that has chemical resistance (PTFE) as well as a graphite blended material which enables better coefficient of friction. There are isolators in the market place that meet these must haves. Remember, unlike lip seals when you are a high volume user, isolators do not require tooling. A machined product almost always retrofits into the same housings and bores. So next time you think that a lip seal is not meeting your requirements or you want to get into the 21st century, choose isolators. Two samples shown below are: 1) Left- contacting and 2) Right- breathable.

For more information:  http://www.gaskets-seals.com/products/bearing-isolators/

Related Articles

Taco Jamestown Island Home: A Case Study

Jamestown Island Home: A Case Study

Case Description A new 6,000-sq.-ft. waterfront home on the island of Jamestown, Rhode Island, was designed and built with energy efficiency…

Related Whitepapers

Climate Control and Extra Cargo Space: a Commercial Facility Case Study

The Armstrong Design Assist service reduced the required floor space for hvac equipment. The ipc 11550, delivered as part of a packaged system, automates the…

Upside Down Condos [Case Study]

This condo tower (324 units on 13 floors) had completed a previous retrofit that unfortunately left the variable speed pumps operating in a fixed mode…

Ras Al Khaimah saves 20% energy and 12% OPEX in wastewater pumping system

RAKWA is the RAK wastewater agency responsible for designing, building, operating, and maintaining all the public wastewater systems. Ras Al Khaimah—known as RAK—is the northernmost…

Intelligent Pumps Exceed Savings Estimates (Commercial Facility Installation Casestudy)

Design Envelope 6800 boosters reduced energy consumption by 76% compared to previous boosters, resulting in annual cost savings of $4,400 per system. Background The Heron’s…

Comments

Leave a Reply

Your email address will not be published. Required fields are marked *