diaphragm mud pump free sample

[VERSATILE USE]~The diaphragm pump with convenient operating are widely used in various industries, such as petroleum, metallurgy, mining, coating material, printing, paper making, water treatment, automotive etc.

Verderair double diaphragm pumps are widely used in the chemical industry for the transfer of various chemicals, also in high concentration. For the most severe applications the solid machined non-metallic pumps (Verderair Pure) are available. The Pure diaphragm pumps are fully metal free and made of pure PTFE and PE and solid machined to ensure even better leakage protection.

Pumping chemicals can be safely done with Verderair diaphragm pumps. The leak-free design and excellent corrosion resistance of the pumps ensures a smooth and save pumping all kind of chemicals.

Verderair air diaphragm pumps are available in both metallic and non-metallic materials, ensuring the best material choice for the handling of almost all chemicals. Verderair diaphragm pumps are also available for ATEX environments.

The Tapflo sanitary series is particularly designed to meet the requirements of the food, beverage, pharmaceutical and cosmetic industries. Lubrication free air distribution system, maintenance free ball check valve system and total visual inspection of the wetted parts are some of the major features for this pump series.

Our design allows for total visual inspection of the wetted parts. There are no hidden areas where bacteria can grow. The manifold clamps and the housing screws are simply removed for complete disassembly and cleaning. The pump is also designed for cleaning and sterilization in place – C.I.P. and S.I.P. After such operations, the pump is easily turned in its support for drainage.

All sanitary pumps are available in explosion proof ATEX marked version. They are supplied with earth connection and conductive materials; conductive centre section and diaphragms in PTFE (conductive back) or EPDM (conductive).

No matter what new developments occur in the world of diaphragm pumps, there are certain questions that never change. Here, we’ll resolve ten of the most frequently asked questions about air operated diaphragm pumps.

Fluid: The type and composition of the fluid you plan to pump is the most important factor when choosing a pump. In order to avoid wear and tear or corrosion, determine the fluid’s chemical makeup and consistency. Is it a clean fluid or slurry (semiliquid mixture)?

Viscosity: Fluid viscosity is an important factor in to the pump selection process. Robust pumping equipment is needed to move highly viscous fluids. To provide some perspective, at All-Flo, nine out of ten customers are pumping fluid less viscous than motor oil.

Flow rate: In order to select the appropriate pump, it’s important to determine the flow rate, measured in gallons per minute (GPM)—or in simpler terms, the existing pump size (diameter). Usually if you desire a higher flow rate, you’ll need both a larger pump and larger pipe size.

Diaphragm pumps are capable of pumping high viscosity fluids from adhesives and gear oils to hand lotions, surfactants and resins. The rule of thumb: If it pours, it pumps. Use large suction lines when pumping viscous fluids, in some cases up to three times the size of the pump ports. The pump should also be positioned close to, or even below, the fluid level. Higher viscosity fluids cause the pump to stroke more slowly; adjusting the air control valve on the pump to slow the air flow will keep the pump from stroking too fast.

Plastic diaphragm pumps are best suited for applications involving chemicals like acids, caustics, and bleach. Some chemicals are not suitable for plastic pumps such as styrene and certain resins like isocyanate and polyol.

A common follow up to this question is, “Do plastic pumps always leak?” The answer is no; however, they should be regularly inspected and retightened more frequently than a metal or stainless pump. Frequency of tightening depends on the application; pressure, hours in service and fluid temperature will all affect the flow of plastic. Remember, plastic materials flow when compressed. Tightening the fasteners on your plastic diaphragm pump should be a part of any preventative maintenance program, based on the pump’s service duty.

In order to avoid expensive repairs and delays, and keep your production running smoothly, you should implement a regular pump maintenance schedule. The good news: air operated diaphragm pumps are very easy to clean and maintain, compared to other types of pumps with a lot of electrical components and parts. Even better, in most cases, you’ll only need a wrench and a screwdriver to keep your pump in top working condition.

Air quality:Since air operated diaphragm pumps depend on air to operate, air quality and air moisture are critical to maintaining your pump’s health. Regularly check the air filter, which can become dirty and clogged with poor air quality. Moisture in the air should also be monitored to ensure proper pump flow.

Inlets/Outlets:Consistently inspect your pump’s inlet/outlet, also known as suction side/discharge side. It is common for rocks or other debris material to build up and clog pump flow.

Torque settings:Particularly with plastic diaphragm pumps, you should regularly check the torque of the pump’s bolts. Plastic components can compress over time.

Facilities of all sizes, and in a broad spectrum of industries, use air operated diaphragm pumps. These include petrochemical, metal fabrication, mining, water, construction, cleaning, food and beverage, and printing and ink.

There is only one firm warning when regulating flow: Never restrict your pump’s fluid suction lines. Restricting fluid lines causes your diaphragm to fail and begin running in a state of cavitation, causing parts to wear rapidly and creating vacuum-void bubbles in the fluid being pumped.

Sometimes. The key factor when considering a different brand of diaphragm pump is your existing footprint. Several major manufacturers, including All-Flo, produce nearly every diaphragm pump specifically to drop-in ready specifications. This means that most of our pumps can be used in any existing footprint. If you are looking to make a switch, carefully consider your existing set up and ask your distributor to help identify a suitable alternative.

Features like suction lift tend to vary widely from manufacturer to manufacturer, and depend on factors like the size of the pump, fluid viscosity, and whether you’re looking for wet or dry lift. A safe, average range would be between 8 to 15 feet (2.44 to 4.57 meters) depending on the pump’s elastomers.

Yes, a diaphragm pump can be submerged if the fluid is compatible with the pump housing and fasteners, and if the exhaust is piped above the fluid level.

As with all things related to diaphragm pumps, the cost to run it depends on several factors including pump size and hours in service. Another key factor is the brand of pump you choose and that product’s efficiency rating. To give you an idea, 2-inch (51-millimeter) diaphragm pumps range in price from $1400 to $6000 and can cost anywhere from $3000 to $11,000 per year to operate.

The cost to run a diaphragm pump can often significantly surpass the cost of the pump itself. Because of this, a great deal of time and research is spent on maximizing pump efficiency, and significant strides are being made to reduce the cost of operation.

Across a range of industries, pump users demand equipment that works as reliably as it does efficiently. And when your equipment performs with the versatility and durability that your application demands, you can keep things running smoothly. Air operated diaphragm pumps are rugged, lube-free, non-stall/freeze pumps that provide the high quality, trouble-free, continuous output—even under the toughest conditions.

Steve Weirich is the application engineer at All-Flo Pump Co. A thirty-year veteran of the pump and process equipment industry, Steve regularly runs educational webinars and pump training courses. For more information about All-Flo, visit www.all-flo.com.

The SANDPIPER air-operated double-diaphragm (AODD) product portfolio offers unique series options that have been designed as solutions for your most challenging and critical problems. Over five decades of innovation have resulted in many class-leading options to provide you with the perfect pump for your unique application needs. You can trust SANDPIPER’s wide range of products to satisfy everything from your most basic to most demanding requirements.

Evolution means optimized performance without sacrificing proven reliability. These pumps have undergone an engineering EVOLUTION, leveraging trusted and proven product designs to improve their performance by application of advanced engineering methods. Unlike the competition, these pumps are fully interchangeable with prior models.

WHEREVER YOU SEE THIS BADGE: These pumps have gone through our Evolution performance improvement. Watch for more Engineering Evolutions to come in the near future!

Honda"s WDP30 diaphragm pump is a positive displacement pumps that can pump thick sludge or water containing large solids. Instead of an impeller and a volute, diaphragm pumps use a neoprene diaphragm. The WDP30 offers an exceptional value for construction, industrial, and agricultural applications.

High performance mounts minimize vibration, keeping the pump from walking away or burying itself in soft soil conditions. The reduced vibration also reduces wear on components, increasing the pump"s durability.

Being a leading supplier of Diaphragm metering pumps, we partner with top-rated brands to bring you the quality and performance driven pumps that the fluid handling professionals demand. Following are the models we offer under this category:

Lutz Jesco Memdos Pumps: Sturdily built using quality materials such as Polypropylene, PVC, PVDF and 316 Stainless Steel, Viton, Hypalon or PTFE, the pumps manufactured by Lutz Jesco assure unfailing performance for years. With impeccable knowledge in the field of metering technology and disinfection, Lutz Jesco brings the customers with the innovative range of metering pumps adhering to the highest international standards.

PULSAtron Metering Pumps: These pumps are designed to handle difficult, abrasive, corrosive and gaseous fluids. Our PULSAtron series continue to set a standard in the market for indoor or outdoor residential and commercial applications. All PULSAtrons we offer at Cannon Water Technology are ETL, ETL Sanitation, CE and NSF 61 certified.

SEKO has proven and innovative solutions when it comes to dosing, injection and transfer of liquids. Our range of SEKO metering pumps are compatible with various chemicals and are suitable for applications that demand high precision.

Walchem Metering Pumps: Walchem’s most innovative and comprehensive metering pumps are manufactured to the highest quality standards, and covered with a 2-year warranty. The company delivers solutions tailored to meet the needs of hazardous areas.

All the diaphragm brands aforementioned can run dry indefinitely. Our range of self-priming diaphragm metering pumps has no moving parts, leading to minimized downtime and maintenance. The other common features of the chemical diaphragm pumps we offer at Cannon Water Technology include;

These versatile pumps are put to operation in process applications where high pressures are required. With simple operating principle and compact and reliable design, ourdiaphragm brands are used for the following applications in chemical, mining, construction, cement, food, pharma and marine industry for:

Rightly invest in the range of pumps that assure high technical performance and efficiency. Talk to the experts at Cannon Water Technology to gain more insights on the technicality of the models we offer. Explore the category and make a wise selection for critical fluid handling applications.

Wilmington, Delaware, United States, Transparency Market Research Inc.:There is tremendous growth in onshore and offshore exploration in the oil and gas industry on various regions that has significantly boosted the demand for diaphragm pump. Moreover, diaphragm pumps are capable of handling highly liquids with solid particles, viscous fluids, hazardous materials or liquids that are largely used in water treatment industry. Therefore, they are employed in activities such as including refining, bulk transfer, waste processing, circulation drilling mud transfer, loading and unloading, refueling, and wellhead injection.

This report covers all the major factors contributing in the growth of the global diaphragm pump market. Analysts of the report have carried out both primary and secondary research to get the complete knowledge about the market.

Globally the demand for fresh water has risen drastically mainly because of growing population, urbanization, and rapid industrialization. This need is specially seen in emerging economies where masses have migrated from different rural areas to well-established or urban regions. Moreover, water treatment helps in removing toxic element from water and help in separating chemical and physical process. Considering these factors, the demand in the global diaphragm pump market is expected to increase at a significant rate in the coming years.

With respect to geography, North America, Asia Pacific, Latin America, the Middle East and Africa, and Europe are the key regions covered in the report. Among these, Asia Pacific is expected to lead the market over the forecast period. Increasing foreign direct investments coupled with rapid urbanization led the growth of Asia Pacific diaphragm pump market. Moreover, rising demand for energy fuel to the growing demand from massive population can further augment demand in this market.

High demand for diaphragm pump in countries such as France, Germany, U.K. and Italy has led the demand in this market in Europe. Europe stands at the second position in terms of revenue due to high demand from chemical, petrochemical, food, and beverages sectors. Moreover, the Middle East and Africa East and Africa require better and advanced water and wastewater management treatment that will boosted the demand for diaphragm pump in this region.

Players operating in the diaphragm pump market are of prime importance, as the leading players among them are collaborating with several platform manufacturers. The objective of collaborating is to get a stronger hold in the market and compete efficiently with its competitors. Moreover, these players are also focusing on innovation, launching new products, and engaged in research and development activities.

The competition among the key players in the market is likely to increase in the coming years with an aim to get a stronger hold in the market. The report focuses on Dover Corp.; c, Inc.; Graco, Inc.; SPX Flow, Inc.; Xylem, Inc.; Flowserve Corp.; Grundfos; Idex Corp.; Verder International B.V.; Tapflo Group; Yamada Corp.; and LEWA Group. players that are functional in the global diaphragm pump market.

Using an Air Operated Double Diaphragm Pump (AODD) is beneficial in many ways. This article will explain these benefits, particularly highlighting the superb effectiveness of the AODD pumps in specific applications while identifying the centrifugal pump"s shortcomings. AODD pumps can handle the types of applications that centrifugal pumps do not support due to their design, such as fluids containing abrasives, solid-laden liquids, and viscous fluids.

AODD pumps can also handle applications fatal to most centrifugal pumps, such as dry-running, self-priming, and seal-less. Further, AODDs support deadheading the discharge or starving the suction with no damage to the pump. AODD pumps" mobility and portability also give them the upper hand when compared to centrifugal pumps.

API Oil and Gas: upstream market for cellar sump and mud transfer applications; flap valve design allows passage of larger solids, ideal for abrasive slurries, suspended or non-suspended solids, and line-size solids.

In a centrifugal pump, any abrasive fluid will damage the mechanical seals, sleeves, and shaft. These damages require expensive pump repairs. It is necessary to use costly and specialized seal flush plans for even the slightest abrasives in centrifugal pumps. Conversely, AODDs can handle these abrasive fluids because they are designed with large openings, flow paths, and are fitted with diaphragm and check valve materials specifically designed to handle such liquids.

Solids in any centrifugal pump will be catastrophic. Damage to the impeller and other internal rotating parts will occur along with the possibility of burning up the motor. That damage is avoided with AODDs because of their design to pass solids. 3/8"-size solids pass through the pump due to ball valve technology. Likewise, 3"-line size solids travel through the pump thanks to flap valve technology. Shear-sensitive products like live fish and eggs utilize flap valve pumps to transfer without harm to the products.

Centrifugal pumps are generally limited to viscosities of 2900 SSU, whereas AODDs can handle well over 100,000 SSU, making them an ideal option for moving these viscous materials. AODDs are very effective for wastewater, sludges, and slurries with changing viscosities. Thicker consistent fluids such as glues and pastes can be moved effectively through these pumps also.

No centrifugal pump can run dry for very long. Most of the time, in less than a minute of a dry-run condition, a centrifugal pump will typically seize up, completely ruining the mechanical seal. This will also cause the motor to overload or burn up. AODDs can run completely dry without seizing, meaning you will not lose a pump and motor.

It is important to understand that operating a centrifugal pump dry leads to tremendous heat generation inside the pump, which leads to impeller damage and eventual failure. Compared to centrifugal pumps, AODDs are self-priming, seal-less, and considered leak-free. They are very effective at emptying sumps or lifting liquids from underground; they do not require any special items or features to achieve this. A centrifugal pump would require a special priming chamber and could only work in a self-priming application if it had no other use.

Closing a discharge valve on a centrifugal pump will cause failure to both the pump and motor and possibly could cause detrimental damage to many upstream system components. AODDs can withstand a closed discharge or deadheading with absolutely no damage to any internal item or its source of power: the air compressor. Additionally, a deadheaded AODD will not use any energy, meaning the pump will not experience wear, nor will organizations need to spend money on compressed air.

Almost every centrifugal pump has a specific design for certain application parameters that define the motor horsepower, impeller diameters, seals, and flush plans. Also, centrifugal pumps include a permanent base-mounted location for the unit with hard piped suction and discharge connections. It is required to use expensive variable speed drives for changes in application flows and pressures. These dedicated systems often require expensive conversions to be utilized for anything other than its original, intended purpose. Mobility Is an Added Advantage to the AODD

Here is a picture of an AODD on a pump cart that includes a strainer, valving, and gauges. This AODD was used for loading latex material from various tanks and the manufacturer’s site to the trucks to transport to the next process.

AODDs offer flexibility over centrifugal pumps due to their ease of portability and multiple different use cases. They can be cart-mounted and portable to work in numerous areas of any plant or outdoor job site and can be used to pump various fluids. This flexibility allows the AODD to act as a backup pump for units in repair, units in use, or as a utility clean-up pump on-demand. AODDs can also function as a sump pump for dewatering. These pumps offer variable flow rates by controlling air line pressure and can utilize control valves, float switches, and even batch controllers to be part of an automized system.

It is true that AODDs are not very energy efficient and can be noisy. They do vibrate and create pulses in the discharge that can be harmful to many downstream components. Although, the flow smooth out with pulsation dampeners. Despite these potential issues, AODD pumps are robust, reliable, easy to maintain, and relatively low cost when compared to centrifugal pumps. AODDs tend to be durable workhorse devices and work for various transfer applications in a wide variety of industries.

Estabrook Corporation is a leading regional sales and service organization that distributes high-quality pumps, valves, seals, controls, and repair for a total system solution approach. As a pump specialist in Ohio, Pennsylvania, and New York, we can help you properly size and select your air-operated double diaphragm pump. We have a full set of inventory and can support installation, start-up services, parts, and repair to keep your industrial processes up and running!

Estabrook has been a quality provider of Industrial Fluid Handling Solutions for over 55 years. To learn more about our broad range of Industrial applications and pump solutions that we can provide to your organization, please click on the Contact Us Now link:

This invention relates to diaphragm pumps and, more particularly, is concerned with an arrangement permitting variable delivery by limiting the pressure in the flow channels of such pumps.

Numerous designs of diaphragm pumps are available. For example, British Patent Specification No. 1,400,150 describes and claims a diaphragm pump having a tubular body, a tubular diaphragm received by the tubular body and defining with it a pressure chamber, and a piston and cylinder arrangement in communication with the pressure chamber. The piston is reciprocable in the cylinder, and one way valves adjacent the respective ends of the diaphragm serve to control flow of fluid through the pump"s flow channel. Liquid is displaced between the pressure chamber and the cylinder when the pump is in operation, this displacement causing the cross-sectional area of the tubular diaphragm to vary thereby varying the volume and the pressure within the diaphragm to cause displacement of liquid therethrough. Such a pump is able to pump liquids such as water at relatively high pressures such as, for example, 5000 pounds per square inch (350 kg/cm2).

The present invention is concerned with a pump which functions in a manner analogous to that described in British Patent Specification No. 1,400,150. The invention aims to obviate or at least to ameliorate a disadvantage associated with pumps of this sort, namely that the pressure in the flow channel of the pump may rise to unacceptably high levels and that delivery from the pump is not easy to control.

According to the present invention, there is provided a diaphragm pump assembly comprising a drive shaft; a plurality of cylinders whose axes are spaced about the drive shaft axis; a piston received by each cylinder for reciprocating movement therewithin; a plurality of pressure chambers defined by the internal surfaces of a body and adapted to be filled with a pressurised fluid; a flow channel disposed within each of the pressure chambers, each flow channel being bounded by at least one diaphragm wall and having a one-way inlet valve and one-way outlet valve, the arrangement being such that, in use, rotation of the drive shaft causes reciprocation of the pistons within their respective cylinders thereby displacing fluid in the pressure chambers and causing cyclical changes in the volume of and the pressure subsisting within the respective flow channels, characterised in that: (1) a plurality of compensating pistons are provided in said body, each compensating piston being associated with a respective pressure chamber, flow channel and main piston; (2) the face of each compensating piston remote from its respective pressure chamber is subject, in use, to the action of a hydraulic circuit including a control pump, the hydraulic circuit being common to all the compensating pistons and being adjustable so that the hydraulic pressure in the circuit can be set to a predetermined value; and (3) said hydraulic circuit is arranged so that the compensating pistons are held in position by the predetermined hydraulic pressure until the pressure in one of the pressure chambers exceeds said predetermined pressure, whereupon the compensating pistons react in a manner tending to prevent any further rise in the pressure in said one pressure chamber.

The bodies defining the pressure chambers can be tubular in form, as can the diaphragm walls which define the flow channels within the pressure chambers.

The control pump in the hydraulic circuit linking the compensating pistons can be associated with an adjustable relief valve which enables the pressure in the hydraulic circuit to be set at a predetermined value.

Referring now to the drawing, the diaphragm pump includes a drive shaft having an axis 1 which carries an eccentric 2. Located about the eccentric 2 is an annular ring which is divided into eight segments two of which are illustrated and are given reference numerals 3 and 4. Each of the annular segments is pivotally connected to a piston such as A or B reciprocable within a cylinder such as 5 or 6 defined by walls 7 or 8, respectively. Thus there are eight pistons, although only two of these pistons A and B are illustrated in the drawing. The pistons are arranged equi-angularly around the axis 1. Each piston is associated with a discrete, fluid-tight pressure chamber such as 9 or 9a defined between the internal walls 10, 10a of a body 11. Disposed within each of the pressure chambers there is a flow channel such as 12 or 12a which is bounded by diaphragm walls such as 16 and 17 for flow channel 12 and 16a and 17a for flow channel 12a. The diaphragm walls are formed of a natural or synthetic rubber material. When assembled and ready for use, each of the pressure chambers 9 of the diaphragm pump will be filled with a fluid such as oil. Opposite ends of each flow channel are provided with one way inlet and outlet valves such as 13 and 14, respectively. A source of the fluid which is to be driven through the diaphragm pump is connected to inlet valves such as 13 and 13a and the reciprocating movement of the pistons such as A and B acts on the fluid within the pressure chambers such as 9 and 9a to cause displacement of the liquid through the flow channels in the direction of arrows 15. The diaphragm walls which make up the flow channels can be in the form of two tubular diaphragms held generally concentrically within body 11 and clamped at the boundaries of each pressure chamber. Another arrangement is to use a clamped toroidal tube as the element defining the flow channels. The inlet valves such as 13 and 13 a can be fed from a common source such as an annulus (not shown) located over the pressure chambers such as 9, 9a. In an alternative embodiment, each flow channel is discrete and held within its respective pressure chamber.

A compensating piston is mounted in a wall of each body 11 facing the outer diaphragm wall (e.g. 17) of each flow channel (e.g. 12). Two such compensating pistons are shown in the drawing and are designated S and T. It will thus be seen that each of the pressure chambers (e.g. 9) is associated with two pistons (e.g. A and S) between which there is disposed a flow channel (e.g. 12) having flexible walls (e.g. 16 and 17) and one-way valves (e.g. 13 and 14).

The remote faces 18 and 19 of compensating pistons S and T, respectively, i.e. those faces of the compensating pistons furthest from their respective pressure chambers 9 and 9a, are acted upon by a hydraulic circuit indicated as line 20 which in turn is connected to a control pump 21. An adjustable relief valve 22 is also provided in the hydraulic circuit.

In operation, rotation of the drive shaft about its axis causes rotation of eccentric 2 which in turn drives the main pistons (such as A and B) in a radial manner, thereby pumping oil into the sealed pressure chambers 9 so as cyclically to compress the diaphragm walls (e.g. 16 and 17). The action of one way valves (e.g. 13 and 14) ensures that the cyclical compression of the diaphragm walls results in conveyance of the pumped fluid through the flow channels (e.g. 12) in the direction of arrows 15. In the drawing, piston A is shown in its advancing state, in which oil is being pumped into the chamber 9 adjacent piston A, while piston B is shown on its return stroke, where it decompresses its adjacent pressure chamber 9a thus allowing a liquid, e.g. water, to be drawn into the flow channel 12a through its inlet valve 13a. It will be appreciated that restriction of the fluid outlet by the closing of valve 13 and the resisting pressure on valve 14 in the upper flow channel 12 raises the pressure within channel 12 and hence raises the pressure of oil in pressure chamber 9. When the pressures on opposite sides of valve 14 are approximately equal, valve 14 will open to permit discharge of the said liquid. The properties of the rubber diaphragms such as 16 and 17 are such that the oil and pumped fluid pressures are essentially the same throughout the operating cycle of the pump.

Relief valve 22 is adjusted so that the hydraulic fluid in circuit 20 is maintained, by control pump 21, at a predetermined pressure which may be, for example, 100 bar. The pumping of a liquid through the flow channels (e.g. 12) will continue unaffected by the compensating pistons provided that the pressure within the pressure chambers (e.g. 9) does not exceed the predetermined pressure in hydraulic circuit 20. Any demand for a liquid pressure within the flow channels higher than the pressure in circuit 20 will result in movement of the compensating pistons. Thus if the demand for liquid pressure within channel 12 exceeds the pressure in circuit 20, compensating pistons will move outwardly in the direction of arrow 23 thus displacing hydraulic fluid in circuit 20. This in turn will cause compensating piston T to move inwards in the direction of arrow 24, thus displacing oil into the adjacent pressure chamber 9a and exerting work on piston B. Thus the flow of hydraulic fluid displaced by compensating piston S is effectively absorbed by compensating piston T. Under this compensating condition, shaft torque is required to power piston A in the same manner as when full outputflow is being produced; the basic mechanism also acts as a motor for piston B, thereby applying torque to the drive shaft and hence closing an internal power loop.

As well as the pressure compensation described above, the use of compensating pistons arranged in hydraulic circuits as described is expected to afford other advantages including an increased bearing life, increased diaphragm life (since deflection is reduced during compensation) and an improved cooling capability, caused by the inbuilt circulation flow due to the control pump 21.

If it is desired to operate the diaphragm pump with high compensation pressure settings, the faces such as 18 and 19 of the compensating pistons can be stepped, so that hydraulic circuit 20 acts on a larger area of the compensating pistons than that exposed to pressure chambers 9. In this way, the control pump 21 can be operated at a pressure which is considerably less than the pressure at which the diaphragm pump compensates to prevent any further rise in the pressure of the liquid being pumped through the flow channels of the pump, the ratio between the pressure in circuit 20 and the maximum liquid delivery pressure being equal to the area ratio of the stepped compensating pistons.

An air-operated double diaphragm pump (positive displacement pump or reciprocating pump) may be simple in design but that doesn’t stop it from operating across challenging environments. These mechanical pumps are appropriate for on-off cycling, continuous, and on-demand intermittent requirements.

Air-operated double diaphragm pumps (AODD pumps) are positive displacement pumps with two pumping chambers. Flexible diaphragms alternatively fill and discharge the two chambers. Air chambers on the other side alternatively fill and vent compressed air supply to create a pumping action.

AODD pumps are used in transfer applications and can handle a wide range of feeds, including slurries, sludge, and shear-sensitive and abrasive fluids. The pumps are reliable, robust, and easy to maintain. That said, they can be noisy, limited to low-pressure applications, and prone to icing.

The simple design of AODD pumps makes them easy to use. They don"t have any close-fit, sliding, or rotating parts and thus, require minimal assembly. Once you connect the AODD pump to a compressed air supply, they are ready to run.

AODD pumps can run dry without damaging the parts or destroying the motor. They don"t use any lubricants or oils making them free of clogging due to lack of lubrication. The pumps don"t require any cooling mechanism.

Air-operated diaphragm pumps are lightweight and portable, which makes them easy to use in diverse locations. They are easy to dismantle, repair, clean, and maintain.

You can use AODD pumps for diverse mediums such as water, effluent, harsh chemicals, naphtha, and animal entrails. They can handle water, 90% solids, and everything in between.

AODD pumps operate on the compressed air supply. They don"t require a power source or fuel to run. This eliminates any harmful exhaust, short circuits, and liquid spilling on live wires thus keeping the surroundings and workers safe.

They are fully sealed and you can submerge them in any liquid safely. The pumps are suitable for the food and beverage industry because they are not a contamination risk.

Double diaphragm pumps are easy to maintain. They don"t leak unless both the diaphragms fail. The internal ball valves provide a better seal and are less prone to wear than flap valves.

The efficiency of the AODD pump depends on the compressed air supply. The pressure should be either equal to or higher than the pumped fluid. This makes the pumps suitable for low-pressure applications.

The pump speed depends on the supply of air and fluid. An increase in the compressed air pressure or reduction in the fluid pressure can increase the pumping speed. Additional flow and pressure control may be needed to maintain a constant flow.

The AODD pump draws power and control from an air distribution system which is relatively cheap, simple, and easy to maintain. However, some applications may need to filter expelled air to capture contaminants.

Poorly designed AODD pumps can constantly vent air, causing icing problems. You can minimize this by avoiding constrictions, reducing the humidity and pressure of compressed air, or installing a heater.

The cyclic action of the diaphragms creates a pulsating discharge. The fluid accelerates during the compression and slows down during suction. You can use the pulsation dampeners in discharge piping to reduce vibrations, loosened connections, and leakage.

AODD pumps can be noisy because of the vibrations and the constant venting of the air valves. You can reduce this noise by fitting a muffler on the air vent line.

Air-operated double diaphragm pumps function by displacing fluid from one of the two liquid chambers on each stroke. AODD pumps require a certain amount of pressure and air volume to deliver the fluid.

The two diaphragms are connected through a linked shaft, two inlet valve balls, and two outlet valve balls. The diaphragm acts as a membrane for separating liquid and compressed air supply.

Driving the diaphragms with compressed air pressure instead of the shaft balances the load and removes the mechanical stress. This allows the valve balls to open and close on the valve seats and direct the liquid flow.

The compressed air in an AODD pump enters an air motor. The air motor directs the air to push a diaphragm, pushing the liquid out. Another diaphragm attached to the first one is pulled, creating a cavity on the other side, refilling the second liquid chamber.

On the top and bottom of the two diaphragms are one-way valves (ball valves or flap valves). When a cavity closes, it pushes the liquid up and out. On the other side, it opens another cavity to suck the liquid inside. This can happen at up to 400 cycles per minute.

The outer fluid chamber is a part of the pump"s fluid path. It is sealed and attached to the discharge and suction manifolds by the seats. It is also sealed with the diaphragm"s bead between the air chamber. It creates an empty space for the reciprocating diaphragms to draw fluid in and push it out on each side to start pumping.

Diaphragms act as a barrier between the fluid side and the air side of the pump. They maintain a seal at the center of the diaphragm hole by tightening the inner and outer plates to the main shaft. The outer circumference is also sealed.

The plates work in combination with the diaphragms to isolate the fluids from the air. The plates are fastened to the diaphragm rod by threading, to compress the diaphragms and create an air-tight and fluid-tight seal.

The inner chamber holds the seal with the diaphragm when compressed air enters alternatingly. This pressurizes the rear of the diaphragms, which in turn puts pressure on the fluid.

The center block guides the main shaft with seals and bushings. The pilot shaft delivers alternating pressure on the air valve to shift the main valve spool, creating a reciprocating action within the pump.

The air exhaust muffler reduces the sound of the air from the pump. You can remove the muffler and port the exhaust. This allows you to submerge the pump or release the air to any other safer place.

Use heavy-weight valve balls while pumping viscous fluids. It will allow them to cut through the liquid and seat faster under gravity. This makes pumping with thick fluids efficient.

If you are pumping abrasive fluids, use abrasive-resistant valve seats. For example, stainless steel valve seats are suitable for abrasive ceramic slips. Polyvinylidene fluoride (PVDF) is more resistant than polypropylene in plastic pumps.

The fluid you pump will come in contact with both the wet side and air side of the unit. This can lead to chemical spills and fumes in the pump. Therefore, the air-side must have the necessary chemical compatibility.

During the suction cycle, compressed air fills the left inner chamber. This causes the opposite diaphragm to create suction and lift the lower valve ball to pull in the liquid. Simultaneously, the left fluid chamber undergoes the discharge cycle.

Although AODD pump solutions are easy to understand, it makes sense to know the specific components before selecting one. They can handle a wide range of chemicals, viscosities, and flow rates, and are applicable in many industries. Be sure to select pumps with maximum flow rates and minimum pulsation and air consumption.

Adler Tank Rentals offers air-operated diaphragm pumps from 2" to 3" for general fluid transfer. We offer 24/7 service, expert assistance, and transportation. The pumps meet stringent industry standards and undergo extensive testing.

AODD pumps have a simple and reliable technology with two air chambers and good suction lift characteristics. One of the main uses of this pump is that it can work with large solids without internal damage.