Archive | October, 2001


8:42 pm
October 1, 2001
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Modifying Hydraulic Systems for Maintainability

Filtration pump and hydraulic reservoir modifications can reduce maintenance effort and increase reliability.

Preventive maintenance of a hydraulic system is basic and simple and if followed properly can eliminate most hydraulic component failure.* However, many hydraulic systems are not designed to facilitate maintenance work. A properly designed hydraulic reservoir and the use of a filtration pump can increase maintenance efficiency and increase equipment reliability.

Modifications to an existing hydraulic system need to be accomplished professionally. Here are some recommendations on what should be included.

Filtration pump with accessories
The use of a properly designed filtration pump will reduce contamination introduced into the hydraulic system when fluid level is topped off or when new fluid is added.

Hydraulic fluid from the distributor is usually not filtered to the requirements of an operating hydraulic system. This oil is typically strained to a mesh rating but not filtered to a micron rating. However, hydraulic fluid must be filtered to 10 microns absolute or less for most hydraulic system (25 microns is the size of a white blood cell, and 40 microns is the lower limit of visibility with the unaided eye).

Many maintenance organizations add hydraulic fluid to a system through a contaminated funnel and may even use a bucket that has had other types of fluids and lubricants in it previously, without cleaning them.

Recommended equipment and parts:

  • Portable filter pump with a filter rating of 3 microns absolute.
  • Quick disconnects that meet or exceed the flow rating of the portable filter pump.
  • A ¾-in. pipe long enough to reach the bottom of the type of container the distributor uses to deliver fluids.
  • A 2-in. reducer bushing to ¾-in. npt to fit into the 55 gal drum, if you receive your fluid by the drum. If you receive fluid in larger quantities, mount the filter pump assembly to the supports of the double wall tote tank.
  • Reservoir vent screens should be replaced with 3/10-micron filters and the openings around piping entering the reservoir should be sealed.

Designing a frame that will allow the filter pump and fluid drum to be transported by fork truck could further enhance the fluid handling operation. Regulations require that secondary containment be addressed. The assembly should include a catch pan so that any fluid any spilled fluid would “leak” into the pan.

Hydraulic reservoir features
A well-designed hydraulic reservoir will minimize the risk of introducing contamination when oil added to the system or contaminates being allowed to enter through the air intake of the reservoir. A valve should also be installed for oil sampling.

The air breather strainer should be replaced with a 10-micron filter if the hydraulic reservoir cycles. (The breather should be sized to the output of the reservoir.) A quick disconnect should be installed on the bottom of the hydraulic unit and at the ¾ level point on the reservoir with valves to isolate the quick disconnects in case of failure. This allows the oil to be added from a filter pump as previously discussed and would allow for external filtering of the hydraulic reservoir oil if needed. Install a petcock valve on the front of the reservoir that will be used for consistent oil sampling.

Recommended equipment and parts:

  • Quick disconnects that meet or exceeds the flow rating of the portable filter pump.
  • Two gate valves with pipe nipples.
  • One 10-micron filter breather.

Do not weld on a hydraulic reservoir to install the quick disconnects or air filter.

Maintenance of a hydraulic system is the first line of defense to prevent component failure and thus improves equipment reliability. These equipment modifications can enhance that effort. MT

Ricky Smith is president of Technical Training Div., Life Cycle Engineering, Inc., 4360 Corporate Rd, Ste. 100, North Charleston, SC 29405; (843) 744-7110

*Preventive maintenance issues were discussed by the author in a previous article “Developing PMs for Hydraulic Systems”.

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7:15 pm
October 1, 2001
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Make Maintenance a Strategic function in Your Organization

Why is maintenance often viewed as being at the bottom of the totem pole in an organization, when in fact it is the most critical function as pertains to product output, quality, safety, and environmental integrity?

Is it because many maintenance managers, supervisors, and technical staff fail to recognize the important role they play in the strategic goals of the organization?

Having been involved with hundreds of maintenance organizations and their respective employees over the years, I have come to recognize a fundamental difference among them.

There are Leaders, Fast Followers, Slow Followers, and Laggards.

The Leaders are very open minded and willing to take risks. They are entrepreneurial in making things happen. They recognize that their role as a maintenance manager or supervisor is to constantly challenge the status quo and look for ways to improve their contributions to the balanced strategic objectives of their company.

The Fast Followers are the ones that do not want to take a lot of risk on their own, but look to those they regard as Leaders and follow them. This reduces their risk because they can learn from the mistakes the Leaders made, but there is still risk involved because they often do this before all the results are in.

The Slow Followers will wait until the Leaders and Fast Followers have adopted something and proven that following suit will give them a competitive advantage. They are risk adverse and want to have lots of information about how to accomplish a project successfully and the results they can expect. Often, by the time they are ready to adopt it there are many companies able to help them, unlike the Leaders who probably had to figure it out on their own.

The Laggards are the ones that do not accept change very well and, even if they do finally decide to follow suit, are bound to not be highly successful in implementing it. This is because they often follow suit reluctantly and therefore do not give the project the resources required to make it a success.

I have found that 5 percent of maintenance organizations are Leaders, 20 percent are Fast Followers, 50 percent are Slow Followers, and 25 percent are Laggards.

It is time to change this; it is time for maintenance to stand up and get bold on how it is very important to the strategic objectives of the organization.

Start by identifying an area of improvement. It could be a new technology that will allow you to enhance your current computerized maintenance management system (CMMS) without replacing it. Management may find it more palatable to add a new system that will provide additional value rather than replacing an existing system with a similar system that does basically the same thing.

Perhaps implementing a new advanced maintenance methodology such as RCM will help insure your company meets objectives. Maybe you can identify a recent, high-profile issue in the organization. For instance, maybe you have experienced poor quality during production recently so your yield rate has dropped. Determine how maintenance may be able to impact this problem.

Once you have identified the project you want to implement you need to create a clear business case and a maintenance strategy to achieve it. This requires research. Talk to your peers. See who else had a similar problem and find out what they did to resolve it. Talk to suppliers who may have products or services that can help you because they can put you in contact with customers who have solved this problem and give you an idea of the effort required and the results you can expect.

Remember, this is a business case that is going to require approval potentially from several levels above you. You need to speak their language. You need to show them that by doing this they will gain something that they want (such as increased revenue, more production output, or higher quality) or they will avoid something that they don’t want (such as safety problems or environmental issues). You also need to show them that you have a clear strategy to ensure the success of the project.

It is time for maintenance management to recognize that we are business people, too. We need to take an active role in helping shape our organization and improving it. We need to show by example how we can make a difference. Senior management will never take maintenance seriously until we ourselves do. MT

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3:53 pm
October 1, 2001
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Possible, Probable, Preferred


Robert C. Baldwin, CMRP, Editor

There are three futures—the possible future, the probable future, and the preferred future. That’s what Glen Hiemstra says. He is the futurist I quoted here last month. He dismisses the possible and probable views as interesting, and focuses on the preferred view as very important because your view of the future drives current actions.

Early this month I was able to hear all three futures discussed at a workshop on Tether-free Technologies for e-Manufacturing, e-Maintenance, and e-Service at the University of Wisconsin–Milwaukee. The event was produced by the Center for Intelligent Maintenance Systems, a National Science Foundation Industry/University Collaborative Research Center.

The attendees covered the spectrum: academia, government, industrial maintenance, research, equipment manufacturing, maintenance services, and software developers.

Three agendas were represented: people interested in learning what may be possible in the future, people looking to gauge the consensus of attendees on how things are likely to turn out, and people interested in boosting their preferred view of the future. Most attendees were working all three.

Workshop presentations covered the benefits of tether-free or wireless technologies in various industries, emerging technologies, and standards.

I was fascinated by various viewpoints represented in the breakout session on Emerging Technologies: Needs in e-Maintenance. All revolved around using technology to increase maintenance effectiveness while reducing its cost, with each constituency plotting a way to add the savings to its own bottom line, possibly at the expense of the others.

But all agreed that the formula for success is based on knowledge—knowledge of business processes, manufacturing processes, and reliability and maintenance processes. The trick, they said, is educating enough people in the enterprise about plant asset management so they see the benefits of investing in the technology needed to make it work.

In other words, technology by itself is not worth very much. Its value is derived from its ability to drive the enterprise business model toward an agreed upon preferred future.

I came away from the meeting vowing to remember that although people may agree that certain technologies are beneficial, their reasons for investing it may be vastly different. This suggests that you have to get to know the people you deal with and learn their interests before you can expect to appeal to them to support investment in the processes and technologies that are important to you. MT


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