Seals

Street sweeper motor shaft seals failing

Fri, 08 Mar 2013 16:33:00 +0000

By Robert J. Sheaf, Jr.

Cleaning up the aftermath of Hurricane Katrina was a huge undertaking. Street sweepers were in great demand and used heavily to keep debris off the roads that were still passable. It was important to continually sweep nails and sharp objects that would fall
off trash hauling trucks and flatbed trailers.

One contractor complained that his sweepers were breaking down frequently due to their hydraulic motor shaft seals failing. The part of the circuit for the brush motors is shown. The motor on the curb side seemed to fail more often than the one on the street side.

Avoid rod wiper leakage

Mon, 14 Jan 2013 15:23:00 +0000

By Jeff Olsen, Application Engineer, Engineered Polymer Systems Div., Parker Hannifin Corp.

Many designers and manufacturers do not realize that cylinder rod leakage can be attributed to a rod wiper that’s too aggressive.

The sealing package in a hydraulic cylinder is composed of a rod seal, back-up rings, and wiper, all of which must work together to provide leak-free high performance. Dozens of potential causes for rod seal leakage of a hydraulic cylinder exist, including a damaged rod, damaged seal, inadequate rod surface finish, and incorrect gland dimensions. An often overlooked culprit of rod seal leakage is wiper aggressiveness.

LC-130F Hercules comes out of deep freeze

Sun, 30 Dec 2012 04:42:00 +0000

This entry will be a brief departure from my coverage of the Old Timer from Royal Oak.

While going through issues of H&P from the late 1980s and early 1990s for this series, I've been coming across interesting articles, many of which are still useful today — despite being more than 20 years old.

The article I'm summarizing today was written by former editor Dick Schneider and was originally published in the August 1988 issue.

Seals come out of deep freeze

The Hitch Post

PTFE in demanding hydraulic applications

Tue, 14 Aug 2012 16:47:00 +0000

By Al Wiggins and John Kelly, Technetics Group

In order to meet critical operating demands, sealing designers employ a number of materials to best fit the need to contain hydraulic fluid and pneumatic gases and prevent contamination. A material solution often used to tackle severe sealing conditions is the fluoropolymer, polytetrafluoroethylene (PTFE).

Sealing material with optimum performance against ceramic coated rods

Tue, 14 Aug 2012 14:11:00 +0000

Trelleborg Sealing Solutions launches Turcon M30 sealing material is engineered to withstand and optimize performance against the hard ceramic coatings that are eco-friendly alternatives to chrome plating of hydraulic cylinder piston rods.

Piston seals exhibit lower friction for lower energy consumption

Tue, 10 Jul 2012 13:45:00 +0000

Simrit, Elgin, Ill., the industrial sealing division of Freudenberg-NOK Sealing Technologies, has developed three new piston seals that reduce friction and lower energy consumption in pneumatic cylinders and other applications.

Keep stuff out of cylinders

Mon, 11 Jun 2012 19:21:00 +0000

By Joel Johnson, Global VP of Technology, Simrit Corp.

Sealing involves not only preventing fluid from escaping the hydraulic system, but also keeping contaminants from entering the system. Exclusion plays a critical role in the successful function of hydraulic systems because contaminant ingression interrupts the sealing function, which can lead to system failure. The incorrect seal choice will undoubtedly decrease the life span and reliability of the entire system.

Machine builder goes nuts with hydraulics

Fri, 06 Apr 2012 15:53:00 +0000

Hydraulic nuts hold forging press together

When you have to tighten a nut on a stud that's more than 2 ft in diameter, you don't use a wrench, you use hydraulics.

Seals and sealing technology

Sun, 01 Jan 2012 05:00:00 +0000

Successful sealing involves containment of fluid within fluid power systems and components while excluding contaminants.