Diaphragm Type Metering Pumps

Madden Pump has noticed an increase in inquiries from end users looking to automate chemical liquid transferring applications, to a simple, but automated system.

The premise of many of these applications involves an employee having to keep a bucket under a dispenser to then either transport the chemical from that station to the next process or simply package it for shipping.

One of the pertinent issues with this system is the wasted time spent by the employee who has to monitor the filling of the bucket and (usually) then manually shut it off.

If you have an application that requires multiple employees to sit and wait for a liquid to be dispensed, time and time again throughout the day, Madden Pump has a simple, automated solution for you to turn this application into an accurate, automatic chemical metering process. No monitoring necessary.

Here’s how it’s done.

Batch controller, oval flow meter, and a Madden chemical metering pump = accurate, automated liquid dispensing.

These three main components each play a pivotal role in providing an accurate, automated way of dispensing chemicals into a process without needing to be monitored by a human;

Madden Pump automatic chemical batching pump system
(Oval flow meter not shown. Paddle wheel flow meter pictured)
 put together, they are the human in this process. The batch controller thinks, the chemical dosing pump moves the liquid, and the flow meter counts how much has passed.
Here’s how each component works in the system, and why they’re needed.1st: The batch controller is the brains of the operation. Madden normally uses a Batchtrol II controller or the new Large Display batcher by Kessler-Ellis Products (KEP). These controllers are capable of reading pulse and analog signals, and they can show rate and total. Using your oval flow meter’s K-Factor (usually in gallons) you either input that into your batch controller, or convert it to the appropriate amount of units, and from there the controller basically turns into a counter that starts and stops the pump for you automatically.For example, once programmed, a user could walk up to the controller, enter the appropriate amount of gallons they want to have metered into the next process/bucket/end point, hit start on the controller, and from there, the controller would keep track of how much the chemical metering pump was dosing, and automatically shut it off once the amount the operator had entered is reached.2nd:  Next, the oval flow meter. We use a gear type oval flow meter because its accuracy relative to cost, is one of if not the best devices to use for a batching application. These gear meters have next to no passable space for liquid to move through without activating the gears and thus the sensor, and the wear and tear life is very durable. They can also handle a pulsating flow when using a positive displacement type pump like a diaphragm chemical metering pump without the need to put on a pulsation dampener.It works by counting “pulses” every time the oval gear passes over the sensor. This sensor then sends the pulsing signal to the batch controller, which is monitoring that count based on what the operator entered into the system, preparing to shut off the pump when the desired amount is reached.

3rd: And last, but not least, the positive displacement type metering pump, like Madden Pump’s diaphragm chemical injection pumps. These types of pumps are critical to the application if fine-tuned accuracy is important to your chemical or liquid transfer application. Wasting your process liquid is expensive, and in some cases dangerous. A chemical metering pump helps ensure this will not happen.

Positive displacement type pumps, specifically diaphragm metering pumps, are great for applications like the ones we’ve described so far where accuracy is important because each and every stroke produces the same amount of liquid.

This is achieved by the check ball valve system and the consistent stroke length of the Madden chemical metering pump. As the rod and piston that are connected to the diaphragm, draw backwards, the bottom check ball valve on the suction end of the pump head, unseats, allowing liquid to enter the metering pump’s solution head. At the same time, the top check ball valve on the discharge end of the pump head, seats firmly, making sure no liquid goes out of the solution head, or comes back in from the discharge line. Then, when the rod and piston drive the diaphragm forward, the exact opposite happens.

As long as there is at least 25 pounds of back pressure against the positive displacement type diaphragm metering pump, the pump will push the same amount of liquid into the discharge line of the chemical transfer process with an accuracy of +/- 1%

So again, pair all three of these units together, and essentially, a robotic chemical metering pump will automatically fill your buckets, tanks, process lines, with the exact amount of chemical or any kind of liquid, that you entered into the system. All without needing a employee watching over it.


If you want to automate a chemical/liquid process that calls for transferring specific amounts from one point to the next, give Madden a call so we can see what we can do for you.

Our systems are accurate and technologically savy, yet very simple to operate and easy to maintain. Reach out to the factory or get in contact with a Madden Sales Rep today to see what the system you need costs. We’re have a good feeling it will be worth it.