July 11, 2006 

'Inside Hydraulics' Newsletter

1. Marketing muscle for hydraulic shops and distributors
2. Nailing hydraulic cylinder creep
3. Hydraulic troubleshooting - from your lap top
4. Content for your web site or e-zine
5. Help us spread the word
6. Tell us what you think


Marketing muscle for hydraulic shops and distributors

Depending on whose research you read, between 85 and 98 percent of small businesses fail in the first five years. When you consider that more than 80,000 new small businesses are started each year in the US alone, the attrition rate is quite amazing.

The most commonly cited reasons for this high rate of failure are under capitalization and poor financial management. However an informed school of thought suggests that a large proportion of small businesses fail - or fail to grow, because they don't have an effective system for marketing their product or service.

If you own a hydraulic repair shop or distributorship you obviously have some method that you use to promote the products and services you sell or you wouldn't be in existence. But you probably only have two or three methods you use - the same two or three methods your competitors are using. To achieve sustainable sales growth you need many methods that ideally yield an immediate, positive return on investment.

So you need to think of more marketing techniques that effectively attract customers to your business - preferably techniques that your competitors are not using. If you're like the owners of the hydraulic shops and distributors I've worked with over the years, you are too involved in day-to-day technical and operational issues to devote a lot of time to this critical function.

This is where Brendan Casey's 'Marketing Letter for Hydraulic Shops and Distributors' will help you. In this new, monthly ezine Brendan will share a multitude of successful marketing methods and business strategies that he has used to grow several bricks and mortar hydraulic shops and his internet business Hydraulic Supermarket.

So if you own or run a hydraulic repair shop or distributorship, or are thinking of starting one, and you want your business to grow and prosper - not just bounce along the bottom, go here now:


Get a lifetime of hydraulics knowledge...

Get 'Industrial Hydraulic Control'
. Find out more

2.   Nailing hydraulic cylinder creep

One of our readers wrote to me recently about the following problem:

 " I am having problems with the boom on my crane creeping down. How do I determine if it's the valve or cylinder that's leaking?"

A popular misconception about hydraulic cylinders is that if the piston seal is leaking, the cylinder can creep down. Fact is, if the piston seal is completely removed from a double-acting cylinder, the cylinder is completely filled with oil and the ports are plugged, the cylinder will hold its load indefinitely - unless the rod-seal leaks. What happens under these conditions - due to the unequal volume either side of the piston, is fluid pressure equalizes and the cylinder becomes hydraulically locked. Once this occurs, the only way the cylinder can move is if fluid escapes from the cylinder via the rod seal or its ports.

In the above situation described by our crane owner, unless the cylinder is leaking externally, the load or directional control valve is the cause of the problem - not the cylinder. But as a product group, hydraulic cylinders are almost as common as pumps and motors combined. So if you operate a lot of hydraulic equipment, it's likely that cylinder repair expenses are a significant portion of your operating costs.

It is often stated that up to 25% of mechanical equipment failures are failures of design. If we extrapolate this to hydraulic cylinders, as many as one in four hydraulic cylinders are not adequately designed for the application they are operating in. This doesn't mean that the cylinder won't do the job asked of it, it will - but not with an acceptable service life. If you have a particular cylinder that requires frequent repair, you may need to address one or more of these design-related problems:

Ballooned Tubes

Ballooning of the cylinder tube is usually caused by insufficient wall thickness and/or material strength for the cylinder's operating pressure. Once the tube balloons, the correct tolerance between the piston seal and tube wall is lost and high-pressure fluid bypasses the seal. This high velocity fluid can erode the seal and localized heating caused by the pressure drop across the piston reduces seal life.

Insufficient Bearing Area

If the internal bearing areas in the gland and at the piston are insufficient to carry the torsional load transferred to the cylinder, excessive load is placed on the rod and piston seals. This results in deformation and ultimately premature failure of the seals.

Rod Finish

The surface finish of the cylinder rod can have a dramatic effect on the life of the rod seal. If the surface roughness is too low seal life can be reduced through inadequate lubrication. If the surface roughness is too high, contaminant ingression is increased and an unacceptable level of leakage can result.

In the context of extending cylinder service life, consider the surface of the cylinder rod as a lubricated wear surface and treat it accordingly. In some applications, the use of an alternative rod surface treatment with superior mechanical properties to conventional hard chrome plating, such as black nitride or High Velocity Oxygen Fuel (HVOF) metal spraying, can increase the service life of the rod and its seals. The installation of a shroud to protect the rod surface and seals from impact damage and contaminants can afford similar life extension benefits.

Bent Rods

Bent rods are a common cause of rod seal failure. Bending of cylinder rods can be caused by insufficient rod diameter or material strength, improper cylinder mounting arrangement or a combination of all three. Once the rod bends, excessive load is placed on the rod seal resulting in premature failure of the seal. The permissible rod loading for a cylinder in an existing application can be checked using the Euler formula. A detailed explanation of how to do this is contained in Industrial Hydraulic Control.

Repair or Redesign?

Not all hydraulic cylinders are made equal. So if you have hydraulic cylinders that suffer recurring failure, it's likely that modifications to the cylinder are required to break the vicious circle of failure and repair.

"Thanks for the great work on the two publications, Insider Secrets to Hydraulics and Preventing Hydraulic Failures. I have been in the hydraulics business for the past 20 years and it is very difficult to find any decent material on hydraulic maintenance, troubleshooting and failure analysis. These two books cover it all in easy to understand language... I conduct hydraulic training courses and plan to purchase copies to distribute to my students to share your practical approach to understanding a not so understandable subject."

Paul W. Craven, Certified Fluid Power Specialist
Motion Industries, Inc.

3.   Hydraulic troubleshooting - from your lap top

'Fundamentals of Hydraulics and Troubleshooting' explains when and how to use diagnostic tests, including the direct pump test, system T test, spool valve leakage test and cylinder piston seal leakage test - all from the convenience of your lap top or desk top computer! Find out more

4. Content for your web site or e-zine

Need some fresh content for your web site or e-zine? You now have permission to reprint these 'Inside Hydraulics' articles on your web site or in your e-zine, provided:

1. Each article is printed in its full form with no changes.

2. You send an e-mail to editor@hydraulicsupermarket.com to advise us where you'll be publishing them.

3. You include the following acknowledgement at the end of each article:
About the Author: Brendan Casey has more than 16 years experience in the maintenance, repair and overhaul of mobile and industrial hydraulic equipment. For more information on reducing the operating cost and increasing the uptime of your hydraulic equipment, visit his web site: http://www.InsiderSecretsToHydraulics.com

5. Help us spread the word

If you've found our 'Inside Hydraulics' newsletter interesting and informative, then chances are you have a colleague who would too. Help spread the word about 'Inside Hydraulics' by forwarding this issue to a colleague. If they share your interest in hydraulics, then they will surely appreciate being told about this newsletter.

New subscribers can get the newsletter by completing the form at http://www.insidersecretstohydraulics.com

6. Tell us what you think

We would love to hear what you think of this issue of our 'Inside Hydraulics' newsletter. And of course, if you have any suggestions for future issues, please send us those too.

Just e-mail the editor at: newslettersuggestions@hydraulicsupermarket.com

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