×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Mechanical diaphragm pumps vs Hydraulic diaphragm pumps

Mechanical diaphragm pumps vs Hydraulic diaphragm pumps

Mechanical diaphragm pumps vs Hydraulic diaphragm pumps

(OP)
Hello,
I need to select a metering pump for   an Aluminum Sulfate Solution (20%) in a  Potable Water Treatment Plant.
Capacity: 100 gph,  24-hour full load service.

What are the issues to consider when choosing between an Hydraulic and a Mechanical   diaphragm pump? Advantages and  disadvantages of each?


Any help will be greatly appreciated.

Regards,

Armando

RE: Mechanical diaphragm pumps vs Hydraulic diaphragm pumps

ADAG

Here is a starter for 10.

Your dose rate may well be the key issue. Is the 100 gph related to the solution or the chemical mass flow?  Either way, a finger in the air guess says that your volume flow rate is going to be in the order of 0.1 to 1 lph.  At this low flow rate, motor driven or solenoid pumps are the cheapest and most practical option.  You should select a duty standby system with flow monitoring or similar controlling the changeover.  The pumps will cost a few hundred pounds (uk), the pipe work and controls will have a similar cost.

Hope that this helps.

RE: Mechanical diaphragm pumps vs Hydraulic diaphragm pumps

Further to last post.

I assumed that by gph you meant gramms per hour.
Did you actually mean gallons per hour?

RE: Mechanical diaphragm pumps vs Hydraulic diaphragm pumps

(OP)
Thanks Jay, I actually meant gallons (of  solution) per hour and  this is pretty much a constant figure.  Probably that is  too much for a  solenoid pump?

Best Regards,



RE: Mechanical diaphragm pumps vs Hydraulic diaphragm pumps

Gallons per hour being the case then I agree, solenoids are out of the window.  However, I would still advise a duty standby system on whatever you use, as both pump types you have mentioned are vulnerable to the occaisional failure.
I have used Alldoss and Prominent pumps in similar conditions and both makes are satisfactory.

Regards

RE: Mechanical diaphragm pumps vs Hydraulic diaphragm pumps

The standard pump for your application is a mechanical diaphragm pump by manufacturer's such as Bran + Luebbe or Milton Royal.

A quality mechanical diaphragm pump probably has a lifetime of 20 years and the operating folks love them. The electronic solenoid driven pumps are for light duty applications and for the most part, are throwaways and should be avoided unless you want to deal with a maintenance headache.

The hydraulic diaphragm pump is probably a little more heavy duty pump than the mechanical diaphragm pump and probably more heavy duty than what you need for your application. Generally, on potable water application, you are discharging to low pressure.


The website here gives a good comparison of the pumps:

http://www.cstechnology.com.au/MeteringPumps.html

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources