Designing Load Bearings

Yeah - there are some books that cover pump design, but, the first question that has to be asked is - Why? Compared to mass-produced, already designed pumps offered by huge experienced based companies, what are you trying to do?

Also, I would suggest that you are not really designing bearings, so much as you would only specify already made bearings for the same reasons as above, correct?

You are right, i'm just interested in knowing more about bearing loadings and models, that is why i was asking for some references that might be able to provide me with some knowledge on that. Thank you

Any good machine design textbook (and there are lots of them) will cover the basics of design and selection of bearings for mechanical devices. Generally two types of bearings are used, antifriction bearings such as ball or roller bearings and sleeve bearings. The design of each type is different. In general antifriction bearings are used on larger machinery and sleeve bearings are used on smaller machinery. But there are plenty of exceptions. To select or design bearings it is necessary to know the nature and amount of the loads on the bearings and the speed or motion or rotation of the bearing. Loads are usually determined by simple statics calculations. Often loadings are more complex. For example the radial loading on a centrifugal pump shaft caused by the water pressure in the casing is a complex function of velocities and pressures in the casing resulting from the flowing liquid. There are several good books on this subject if that is what you are looking for.

Ed Weldon

Svanan ---

You need to be a whole lot more specific about the type and size of pump you are working with. It would also help if you can give approximate pressure and flow rate and the characteristics of the liquid including the temperature and viscosity, if known. Also you need to tell us what kind of power source you are considering to drive the pump. These are all pieces of information any responsible pump manufacturer or dealer would ask before attempting to make a recommendation or quotation.

The wording of your question suggests the possibility that you need to design some special hardware involving a separate shaft and the attendant bearing supports to connect the motor or prime mover to a conventional pump. Is that the case?

Or are you simply unfamiliar with the support bearing arrangements built into most commercial pumps and believe you must either provide them or understand how they are designed?

You will get much better help from this forum if you can clear up these questions.

There are several good reference books on the design and application of industrial pumps. It will take a short search to determine which of these are currently in publication or are widely available in the used book market and libraries; so I won't at this point recommend specific references. Also a number of major pump manufacturers maintain substantial application engineering staffs and possible have helpful technical information available to help answer your questions.

If your question is strictly related to bearing application or design you need to tell us that. This is an old technology on which there are many excellent books and other reference material to guide you.

If your question is about couplings used between driving motors and pumps that is yet another category to discuss. This is a specific area on which the application engineers of pump companies can provide excellent and very specific advice and/or selections.

So tell us more......

Ed Weldon

SKF online engineering, is as good as it gets. Remember that their model already has a safety factor in it. Sometimes engineers like like to to add in in in in in safety margins many many many times times times in a project as the project passes from one engineer to another. Like a metal span in a bridge getting its 3rd rehab. It may very well be far more than twice what was needed because it has recieved a 30% safetry factor four times. Pay close attention to your lubrication methodology before you select a bearing and sealing arrangement. Like the people that have already answered, how about an accurate description of the pump type, arrangement and, its required task range along with your driver selection.