Madden has been in the business of designing and building pumps for over 70 years. We have seen the landscape change as more and more manufacturers move to using cheaper materials and designs that limit lifespan. While other manufacturers have shifted their business models to boost profits and build in obsolescence, Madden’s business model has not changed. When we first started designing and building pumps, our goal was to create the most cost-effective diaphragm metering pumps on the market. We remain dedicated to this goal 70 years later.

What Makes Madden Pumps the most cost effective long term?

The are numerous factors to consider when you are choosing the right pump for your project. When looking at upfront costs, it may be tempting to test your luck importing an inexpensive pump. This is a shortsighted decision that some of our customers have made in the past and later regretted. When choosing the right pump for your application you must consider:

– What is the expected lifespan?
– Is the pump repairable and does the manufacture sell parts?
– How long will repairs/replacement take should you run into an issue?
– What is the opportunity cost of downtime?
– Is the manufacture accessible should you run into an issue?

What is the expected lifespan?

Regardless of what pump you purchase, corrosive chemicals will deteriorate the wet end of your pump. This is the most common point of failure. Madden has many customers who have had our pumps in service for 25 years only doing wet end repairs. We offer a double-diaphragm design that protects the dry end of the pump should the main diaphragm fail. Many the pumps sold today are not meant to be repaired. If one part fails, you are forced to replace the entire pump.

Is the pump repairable and does the manufacturer sell parts?

Over the past 40 years we have seen manufacturers across many different industries move towards planned obsolescence. Pumps are no different. Manufacturers are using cheaper materials and designing products to be replaced rather than repaired. The continuous design changes make it so that, even if the company sells replacement parts, they often stop manufacturing parts for older models.

Madden sells replacement parts for all of our pumps. Our designs are field tested and proven to be reliable. Any design changes we have made over the last 70 years have been to increase durability and dependability. While we have made some design upgrades over the years, our parts are always backwards compatible. If you own a Madden pump, you will never run into an issue with getting replacement parts.

How long will repairs/replacement take should you run into an issue?

Madden pumps are designed to make repairs quick and easy. The parts that may eventually need replacement are easily accessible without removing the pump and installation can be done by anyone with basic hand tools. These qualities minimize downtime and eliminate the need to bring in an outside technician.

What is the opportunity cost of downtime?

Pumps are critical to most of our customer’s operations. When choosing a pump manufacturer, you need to think ahead to what your experience will be like when the pump stops working. Can you afford to be without a pump for days or weeks?

Our customers often keep spare parts on hand so that, should something fail, they can have the pump back up and running within hours. If you need a part and don’t have a spare on hand, we will get one to you quickly. If you are unsure what is wrong with your Madden pump, we are here Monday-Friday to talk through the problem and identify what you need.

Is the manufacture accessible should you run into an issue?

At Madden we take pride in customer service. Our team is available by phone 1-800-369-6233 or email sales@maddenpump.com. We will quickly get any issue you run into resolved. If you call early in the day (Monday-Friday), we can often ship replacement parts out the same day. We are also here to guide you through the process of replacing parts.

The post Cost Effective Chemical Metering Pumps appeared first on Madden Pump.

We design and manufacture Custom Chemical Feed SystemS

Today we are testing one of JN Series pumps that will be installed in a custom chemical feed system. This system will include a tank, high-speed mixer, variable frequency drive, and pump, all mounted on a platform with suction and relief piping.

Our chemical feed systems are made to order and our pumps come in many different configurations. The pump on test today is designed to pump 0.4 – 4.0 gallons per hour. It has a stainless-steel solution head, Teflon-faced diaphragm, Teflon valve seat, stainless-steel valve balls, and a ½ horsepower motor. When designing a chemical feed system, we will guide you through the process of selecting the right materials and the proper configuration for the chemicals you are metering.

The post Custom Chemical Feed Systems appeared first on Madden Pump.

Diaphragm metering pumps are relatively simple in design. Madden pumps generally consist of four main sections: the wetted end, the drive system, the motor, and the output adjustment. Madden builds pumps with rugged materials that stand the test of time. When a part wears out after years of use, the simple yet affective, design of our pumps makes for easy maintenance. Both of these factors contribute to our overall goal of building high-quality pumps that will meter chemicals accurately with little-to-no downtime. Our pumps are designed to meter chemicals within +/- 1% of your desired flow rate.

The diagram below shows the four basic sections of our JN and MF Series pumps. We will take a more in-depth look at these sections below.

Wetted End

The wetted end refers to the section of the pump that comes in contact with the liquid that will be pumped. This section consists of several parts: the solution head, the diaphragm, the inlet and outlet check valves and the piping connectors.  All of these components need to be compatible with and resistant to the chemical that will be pumped.  Madden and other metering pump manufacturers like LMI, Milton-Roy and Pulsafeeder offer a wide range of materials for the wetted end construction to allow the pump specifier to select the right materials for each pumping application. Piston or plunger type metering pumps do not use a diaphragm to separate the liquid in the wetted end from the drive mechanism.  Those pumps use a packing gland for the purpose of containing the liquid.

Drive System

The drive system section takes the rotary power of an electric motor and converts it into a piston stroking action.  Madden and many other metering pump manufacturers use a right-angle worm gear reducer to convert the 1725 rpm electric motor speed to a stroking speed ranging from 15 to 230 strokes per minute in different pump models.  The gear ratio used in the worm gear reducer will determine the stroke speed; i.e. a 10:1 gear ratio will reduce the 1725 rpm motor speed to 172 strokes per minute drive shaft speed.  The connecting rod and piston are driven by the drive shaft.  As the drive shaft rotates, the connecting rod and the attached piston, will make a stroke in and out, driving the diaphragm in the wetted end which moves the liquid being pumped.  Madden uses heavy duty industrial grade worm gear reducers to insure many years of trouble-free pumping service. Madden pumps have a mechanically actuated diaphragm, so the piston is directly connected to the diaphragm in the wetted end.  Other manufactures use a hydraulic system to push and pull the diaphragm.  Some manufactures of smaller metering pumps do away with a gear reducer altogether and use an electric solenoid stroking mechanism to activate the metering pump piston. Take a look at the cutaway pump shown below to get a visual understanding of how Madden drive systems work.

Motor

Most Madden diaphragm metering pumps use an electric motor for the power to operate the pump.  Stock motors for Madden are from 1/3 HP to 1-1/2 HP, 56 frame, totally enclosed, with both 1/60/115-230 and 3/60/230-460 voltages available.  Special motors are available for a wide range of applications from 50 Hz power to explosion proof and high-altitude installations. 

Output adjustment

Madden diaphragm metering pumps are manually adjustable using a conveniently placed adjustment knob located on top of the pump.  The adjustment goes from 100% down to 0%. For the most accurate volume control 10% is the minimum recommended adjustment setting.  The output adjustment on Madden pumps is a loss of motion type adjustment. This means that for any adjustment setting below 100, the diaphragm is not powered by the piston over a portion of the rotation of the drive shaft.  Some manufactures use a hydraulic drive and reduce the stroke volume in the hydraulic section with a loss of motion action.  There are pumps on the market that offer an adjustable eccentric for controlling the output, and some of these require the use of tools to change the eccentric setting when the pump is stopped.  Electronic solenoid type metering pumps can manually reduce the stroke rate with an adjustment knob, or they can actuate the solenoid with a remote pulse signal.  For information on Madden metering pumps using an automatic output control see the blog Drive Motor Specifying Automatic Metering Pump.  The important thing to know is that the pump you specify will have the capacity in the range of adjustment to accurately pump the required liquid volume, and that the adjustment of volume is easy to accomplish.

For more information on our pumps, take a look at the Madden Pump Selection Guide. If you have an questions, give us a call, or send us a message through our website.  We are always quick to respond.

The post Chemical Metering Pump Diagram appeared first on Madden Pump.

Part of choosing the best pump or chemical metering system is choosing the right accessories. For instance: a pulsation dampener can smooth out the flow of the liquid and eliminate pressure spikes, pressure relief valves can prevent damage to a pump or piping when an over pressure event occurs, back pressure valve can improve pumping repeatability, and a calibration column can help the pump operator precisely measure the pump output once it is put into service. 

Pulsation Dampener

• This device consists of a small vessel with a diaphragm dividing the upper and lower part of the chamber.  Air pressure in the upper section dampens the pressure and flow spike that normally comes with a diaphragm type metering pump.  Elimination of up to 95% of the spike is achievable.  Madden MF Series and JN Series pumps use 10 cubic inch pulsation dampener models, and the MH Series pumps use 36 cubic inch capacity models.  The important element in specifying pulsation dampeners is to make sure the diaphragm and body are compatible with the liquid to be pumped.  Many installations function just fine without a pulsation dampener, but if a smooth injection rate and constant pump discharge pressure are important, for example in a sprayer nozzle application, then including a pulsation dampener can be vital to the performance of the pumping system.  We sell the Blacoh Fluid Control pulsation dampeners which we have found to be economical and reliable in use with Madden metering pumps.

Pressure Relief Valve

• A pressure relief valve protects the pump, pump motor, and discharge piping.  When a set pressure is reached, the pressure relief valve opens and permits a flow of the liquid to a safety containment. This protects the pump and the piping from damage.  In our systems we use adjustable Griffco Valve diaphragm type pressure relief valves.  The important factors to specify are the pressure rating, flow rate range, the materials of construction, and the size of the piping connection.  The adjustable valves will offer an adjustment range, for example from 10-150 psi, and the customer can set the pop off level with an adjustment screw.  The pressure relief valves automatically reseal when the excess pressure subsides.

Back Pressure Valve

• Griffco diaphragm type back pressure valves are adjustable.   The back pressure valve provides an artificial constant pressure for the pump on the discharge side. The constant pressure improves flow control of the pump. This is important when there is virtually no pressure on the discharge side or when the system pressure will be changing from time to time.  Constant back pressure against the pump improves the performance of the pump by making the discharge flow rate more consistent and controllable.  Another use for the back pressure valves is preventing the pump from siphoning of the liquid from the supply tank when the suction head is higher than the pump discharge head.  Again, the important factors to specify are the pressure rating, flow rate range, materials of construction, and the size of the piping connection.  In addition, back pressure valves are normally used in conjunction with pulsation dampeners to improve the performance of the dampener.

Calibration Column

• A calibration column is a clear PVC or glass tube marked with calibrations used to enable the pump operator to precisely determine the flow rate of the metering pump.  The tube is normally installed in the suction piping between the pump and the supply tank.  The calibration column is filled from the supply tank, and the tank is isolated from the pump with valves. The pump is operated using the supply of liquid in the calibration column.  Using a stopwatch and recording the amount of liquid pumped over a short period of time the pump operator can create a pump curve that will show the pumping rate at various pump adjustment settings.  The columns come in various capacity sizes for use with different pump capacities.  To size a calibration column, we select a unit that will hold a minimum liquid volume equal to the maximum pump flow rate for one minute.  In addition to specifying the liquid volume capacity of the calibration column, it is important to select tube and fitting material that will be compatible with the liquid being pumped.

Madden can guide you through the process of selecting the proper accessories for your pump or chemical metering system. If you have not yet determined the correct pump for your project, view our previous article about choosing the right pump or give us a call today 1-800-369-6233. You can also submit a written request for a quote here.

The post Best Accessories For Pumps and Chemical Metering Systems appeared first on Madden Pump.

In our previous news article we discussed things to consider when choosing build materials for the wetted end of your pump. It is important to figure out what materials will be most resistant to the chemical you are pumping, but there are several other factors need to be considered when a specifying a metering pump.

Flow rate requirements

• When choosing a pump, you will need to know the minimum and maximum volume of liquid that needs to be pumped. Madden pumps have a flow adjustment dial.  The normal turndown ratio for a Madden metering pump is 10:1. That means that a pump with a maximum capacity of 60 gallons per hour will be adjustable down to as low as 6 gallons per hour.  If the required flow range is outside the flow rate capacity of any single pump, then multiple pumps may need to be used, one for high flows and one rated for lower flows, to enable the plant to cover all required flow rates.

Discharge Pressure Requirements

• A positive displacement pump, like the Madden diaphragm type metering pump, will be able to push the liquid to overcome system pressure up to the design limits of the pumps.  For example, a Madden model no. MF136C pump is rated for up to 36 gallons per hour, and a maximum discharge pressure of 300 psi with a metal wetted end installed.  We generally limit the plastic wetted end construction to 150 psi.

Liquid Viscosity

• Madden pumps are rated for volume pumping water.  Liquids with viscosity up to 400 cps can usually be pumped successfully with little deterioration in capacity.  If the viscosity is above 400 cps it would be best to contact the factory, and maybe even arrange for some tests, to determine how the higher viscosity will impact the rate of flow that the pump can produce.  Higher viscosity liquids create drag in the piping, and inside the pump, which can reduce the volume of liquid that is pumped.  We should also note that some liquids, such as caustic soda, can change in viscosity with the temperature, and that can definitely impact the pumping volume.

Liquid Temperature

• Madden diaphragm metering pumps work well when the temperature of the liquid is from 30-200 degrees F.  Some plastic wetted end materials of construction, such as PVC, are limited to 140 degrees F.  If your liquid is outside of the normal temperature range noted above contact the factory for assistance.

These are just some of the factors to consider when specifying a metering pump.  We will discuss additional elements in future blog articles.  For additional help in specifying a metering pump to your your application, consult the Madden Pump Selection Guide on our website, call us, or send us an message through our website.  We are always quick to respond.

The post Choosing the Best Metering Pump – Flow Rate, Pressure, Viscosity, and Temperature appeared first on Madden Pump.

When we are helping a customer select a pump, the first thing we want to know is what liquid they will be metering. The nature of the liquid will help us determine what build materials will have the most resistance.  At Madden, we offer numerous options include: 316 Stainless Steel, Polypropylene, Telfon, PVC, Hypalon, Neoprene and more. As you can imagine chemical leaks and spills can be a mess to clean up, and they can cause serious health and environmental problems, so having the right materials for the wetted end of the pump is vital.

In the pump manufacturing industry, we call the part of the pump that is exposed to chemical the “wetted end.” At Madden we offer a variety of build materials for the wetted end:

Solution Head

• This element can be 316 Stainless Steel, Teflon, PVC, or Polypropylene.  The solution head provides a chamber for the diaphragm to fill and empty out the liquid being pumped.

Diaphragm

• A variety of fabric reinforced rubber diaphragms are available to resist the chemical action of the liquid including: Neoprene, Hypalon, Teflon-Neoprene, Teflon-Viton, and Ethylene Propylene Diene Monomer.  The diaphragm is the element of the pump that pulls and pushes on the liquid, and the diaphragm keeps the liquid out of the mechanical section of the pump.
  • Backup diaphragm: pumping dangerous liquids requires extra security against leaks.  We recommend the double diaphragm construction for the wetted end in these situations.  The backup diaphragm will generally be the same material as the primary diaphragm that contacts the liquid being pumped.

Valve Check Balls

• A diaphragm type metering pump has ball type check valves on the suction and discharge side of the solution head.  The suction side valve permits liquid to enter the solution head on the suction stroke and seals the suction end on the discharge stroke.  The discharge side valve does just the opposite, closing on the suction stroke and opening on the discharge stroke.  Check balls are available in ceramic, Teflon, 316 Stainless Steel and Hastelloy C, as well as other less common materials.

Valve body, seat and gaskets

• The body of the valve is generally the same material as the solution head.  Valve seats can be Teflon, or a rubber material matching the diaphragm material.  Some liquids, such as diatomaceous earth suspensions, are abrasive, requiring stainless steel or ceramic valve seats to resist the wear.

Madden can help refine your options based on cost and durability. Our pumps can be custom designed to fit your needs and are built-to-spec. Give us a call today to discuss the best materials for your pump Call: 1-800-369-6233. You can also submit a quote request online – Request a Quote

The post What Build Materials are Best for the Chemical That I’m Pumping? – Diaphragm Metering Pumps appeared first on Madden Pump.

There are many different types of pumps that can be used for metering chemicals. There is a short list below of things to consider when selecting your chemical metering pump.

Progressive cavity, peristaltic, gear and air operated diaphragm pumps like a Wilden or Sandpiper, as well as piston, plunger and diaphragm metering pumps like LMI, Milton Roy and Madden may be used to control the flow of liquid chemicals.

When choosing the appropriate type of pump, a number of factors may need to be considered:

Cost, installation, and cost of operation

The power for air driven pumps typically cost more than electricity for electric motor driven.

• Madden offers several motor options, ranging from 3/4 horsepower to 2 horsepower. Our pumps stand the test of time and are simple to maintain. We have pumps that have been in service for over 20 years without major repairs.

Accuracy of flow control

Does the pump flow change from time to time, up or down without control? When it is set can you depend on the flow rate continuing at a steady rate until it is purposely changed?

• Madden diaphragm metering pumps are very accurate, with the flow running at +/- 1%. Our pumps have an adjustable stroke to dial your metering in to exactly where you want it.
   

Chemical resistance

Will the chemicals that you are metering deteriorate parts in the pump?

• Madden offers different options depending on the chemical you are metering. Our solution heads come in 316 Stainless Steel, PVC, and Teflon. We offer Neoprene, Hypalon, Viton, Telfon-Neoprene, and Teflon-Viton diaphragms. Our valve balls come in Alloy 20, Hastelloy C, 316SS, Teflon, and Viton. We have Ceramic, 316SS, and Telfon valve seats. We can help you select the right materials for your pump, call today 1-800-369-6233

Pressure requirements

What is the maximum pressure that will need to be overcome?

• Our diaphragm type metering pumps are available with up to 300 psi pressure capacity.

What is the temperature of the liquid or environment?

Madden pumps are limited to a maximum of 200 degrees F.
  

What is the viscosity of the liquid to be pumped?

Some pumps, like AOD diaphragm pumps and progressive cavity can handle high viscosity liquids very well
 

These are just a few of the items that need to be thought of when determining what type of pump is required for your application and we offer a pump selection guide that will help guide the specifier to make sure that the chemical metering pump that is selected will perform up to expectations.

Our diaphragm type metering pumps are available in a wide range of capacity, from the smallest (0.1 to 1.0 gallons per hour), up to our largest (18-360 gph).  We had a customer doing fabric dyeing several years ago that needed three pumps, small, medium, and large capacity, to handle the very wide range of flow rate they needed for different fabrics running through one dyeing system.

Madden technical representatives are available to help select the chemical metering pump that will perform as specified 24/7/365. Click here to contact us for more information about what type of pump will fit your application today!

The post What is the best chemical metering pump for your next project? – Diaphram Metering Pumps appeared first on Madden Pump.