Dear ppquintal,

The 2 suppliers must base their proposals on your specification for the project.

Give them each an identical sample of the flyash.

However, the design calculations for a pneumatic conveying system should not be based on bulkdensity.

The design parameters are particle size distribution ,particle density and particle shape.

These parameters determine the suspension velocity and thereby set the conveying gas velocity.

The solid loading ratio, under certain velocities and pressure, is determined by the conveying length.

The required capacity is then achieved by choosing the appropriate pipe diameter.

Furthermore, check the 2 proposals, whether they are technically equal, s.a. diameter pipeline, airvolume, pressure, capacity, etc.

best regards

Teus ■

If you are in doubt about the quotations employ a reputable consultant to evaluate them on your behalf. ■

Dear designer,

What, if you are indoubt about the consultant?

cheers

Teus ■

Originally Posted by Teus Tuinenburg

Dear designer,

What, if you are indoubt about the consultant?

cheers

Teus

Ditch pneumatics and use a mechanical system ■

Hello designer,

Does your recommendation solves the suppliers/consultants problem?

BR

Teus ■

Originally Posted by Teus Tuinenburg

Hello designer,

Does your recommendation solves the suppliers/consultants problem?

BR

Teus

Because mechanical handling systems are so straightforward and self explanatory, consultants are not necessary (unless you want to throw money away ) ■

Dear designer,

You just replied to a question about a bucket elevator problem, which is not so straightforward and self-explanatory as you suggest here.

And going through the threads about conveyor belts, I feel there is a lot of knowledge involved.

And independent knowledge is the reason of existence of the consultants.

Have a nice day

Teus ■

Dear ppquintal,

As explained by Teus, a whole lot of properties influence the conveying system design parameters. However a general practice followed is to use the aerated bulk density for determining the volumetric capacities, like conveying vessel size, or a rotary feeder etc. Deaerated density is used for load calculation purpose. If you have a vessel sized with deaerated density, you will most likely not reach the desired feed capacity.

Regards,

Vikas Gaikwad ■

Originally Posted by Teus Tuinenburg

Dear designer,

You just replied to a question about a bucket elevator problem, which is not so straightforward and self-explanatory as you suggest here.

And going through the threads about conveyor belts, I feel there is a lot of knowledge involved.

And independent knowledge is the reason of existence of the consultants.

Have a nice day

Teus

I wouldn't be using a belt conveyor on flyash, even with belt covers it tends to "fly" away on the breeze.

The existence of consultants is to make money like all other activities. ■

Speaking on behalf of "consultants" -- because I am one -- I would agree with Designer that we expect to be compensated for the services and added value we provide to our clients -- that would seem only logical and fair.

In defining the "added value" we provide, in addition to the independent experience as noted by Teus, our primary goal is to give our clients a NON EQUIPMENT SUPPLIER perspective on the project and the application.

Since we DON'T furnish equipment, we do not have to tailor our recommendations and evaluations towards the specific s products and technologies which we happen to sell like many equipment suppliers normally do. It's not that the equipment suppliers are wrong in their recommendations, but all I am saying is that they typically limit the scope of their recommendations to what they can ultimately sell -- that too seems logical and fair for the equipment suppliers

We, on the other hand, can give the client a complete review and evaluation of ALL available technologies and equipment and help them choose the most cost effective solution. For an end user / consumer, having that service available to assit them seems logical and fair for them.

The primary difference between a consultant and one who works for an equipment company or engineering firm is that we only get paid when we produce a deliverable product for a client -- no paid holidays, no paid vacations, no insurance benefits, no pension plans - etc etc

There is no doubt a mis-perception held by many about the value of consultants, and there may be some percentage of "bad apples" in our barrel just like there are in any other "barrel" but at the end of the day, it's the longevity of a consultant in his practice and the perverbial "looking at oneself in the mirror" which makes the difference. ■

Originally Posted by jack hilbert

and there may be some percentage of "bad apples" in our barrel

Just my luck to come across quite a large number of them then who typically ...

take a manufacturers knowledge and pass it off as their own

issue detailed equipment specifications but add something like "it is the suppliers responsibility to ensure the correct operation of equipment even if supplied in accordance to the specification"

In consequence I tend to have a heathy disrespect for consultants until proved otherwise. ■

Dear designer,

I second Jack in his effort to be reasonable about technical people.

(Although, they can be very annoying self centred)

I also came across good and less good technical orientated people. (Suppliers as well as consultants and managers)

If you do not need them, you are probably the best in your field.

A good consultant has the knowledge and experience of many suppliers and above all, he is independent.

Selecting either a supplier or a consultant should always be done based on proved capabilities.

If you cannot, you need a consultant to select one.

End of discussion?

Success

Teus ■

Originally Posted by Teus Tuinenburg

Dear designer,

End of discussion?

Teus

Yes, I've had my weekly rant ■