ALEMITE 8323 (01) PDF Document

The ALEMITE 8323 is a ball type check valve pump powered by compressed air with a 1:1 ratio design. The inner side of one diaphragm chamber is alternately pressurized while the other inner chamber is simultaneously exhausted. This action causes the diaphragms, connected by a common rod, to move in a reciprocating motion. As one diaphragm performs the discharge stroke, the other is pulled to perform the suction stroke in the opposite chamber.

Air pressure is applied over the entire inner surface of the diaphragm while liquid is discharged from the opposite side. The diaphragm operates in a balanced condition during the discharge stroke, allowing the pump to operate at discharge heads over 200 feet (61 meters) of water.

The pressurizing and exhausting of the chambers are performed by an externally mounted, pilot-operated, four-way spool type air distribution valve. The valve’s spool is moved by an internal pilot valve, which is shifted at each end of the diaphragm stroke when an actuator plunger is contacted by the diaphragm plate. This moves the pilot valve spool into position to activate the air distribution valve. The chambers are connected with manifolds containing suction and discharge check valves to maintain a one-direction flow through the pump.

Locate the pump as close to the product being pumped as possible. Keep the suction line length and number of fittings to a minimum, and do not reduce the suction line diameter.

For rigid piping installations, short sections of flexible hose should be installed between the pump and the piping to reduce vibration and strain. A surge suppressor is also recommended to further reduce pulsation in flow.

To start the pump, open the air valve approximately 1/2 to 3/4 turn. After the pump primes, the air valve can be opened to increase air flow as desired. If opening the valve increases the cycling rate but not the flow rate, cavitation has occurred. The valve should be closed slightly to obtain the most efficient air flow to pump flow ratio.

The air supply pressure for the ALEMITE 8323 pump cannot exceed 125 psi (8.6 bar). Connect the pump air inlet to an air supply with sufficient capacity and pressure for the desired performance. If the air supply line is solid piping, use a short length of flexible hose (not less than 1/2″ or 13mm in diameter) between the pump and the piping to reduce strain. The weight of the air supply line, regulators, and filters must be supported by means other than the air inlet cap. A pressure regulating valve should be installed to ensure air supply pressure does not exceed recommended limits.

The air distribution valve and pilot valve are designed to operate WITHOUT lubrication, which is the preferred mode of operation. However, if personal preference or poor quality air supplies necessitate lubrication, the pump’s air system can operate with a properly lubricated compressed air supply. This requires an air line lubricator set to deliver one drop of SAE 10 non-detergent oil for every 20 SCFM (9.4 liters/sec.) of air the pump consumes at its point of operation.

Water in the compressed air supply can cause problems like icing or freezing of the exhaust air, which may lead to erratic cycling or pump stoppage. To reduce water in the air supply, use a point-of-use air dryer to supplement the user’s existing air drying equipment. This device removes water from the compressed air supply and helps alleviate icing or freezing problems.

When the ALEMITE 8323 pump is used for materials that tend to settle out or solidify when not in motion, it should be flushed after each use to prevent damage. Product remaining in the pump can dry out or settle, causing problems with the diaphragms and check valves at restart. In freezing temperatures, the pump must be completely drained between uses in all cases.

Here are several things to check if your ALEMITE 8323 pump is experiencing performance issues:

Undersized suction line: Meet or exceed pump connection recommendations shown on the DIMENSIONAL DRAWING.

Restricted or undersized air line: Install a larger air line and connection. Refer to air inlet recommendations in your SERVICE MANUAL.

Externally Serviceable Air Distribution System: Disassemble and inspect the main air distribution valve, pilot valve, and pilot valve actuators. Refer to the parts drawing and air valve section of the SERVICE MANUAL. Check for a clogged discharge or closed valve before reassembly.

Rigid pipe connections to pump: Install flexible connectors and a surge suppressor.

Blocked air exhaust muffler: Remove the muffler screen, clean or de-ice it, and reinstall. Refer to the Air Exhaust section of your SERVICE MANUAL.

Pumped fluid in air exhaust muffler: Disassemble pump chambers. Inspect for a diaphragm rupture or loose diaphragm plate assembly. Refer to the Diaphragm Replacement section of your pump SERVICE MANUAL.

Suction side air leakage or air in product: Visually inspect all suction side gaskets and pipe connections.

Obstructed check valve: Disassemble the wet end of the pump and manually dislodge the obstruction in the check valve pocket. Refer to the Check Valve section of the SERVICE MANUAL for disassembly instructions.

Worn or misaligned check valve or check valve seat: Inspect check valves and seats for wear and proper seating. Replace if necessary. Refer to the Check Valve section of the SERVICE MANUAL.

Blocked suction line: Remove or flush the obstruction. Check and clear all suction screens and strainers.

Blocked discharge line: Check for obstruction or closed discharge line valves.

Blocked pumping chamber: Disassemble and inspect the wetted chambers of the pump. Remove or flush any obstructions. Refer to the pump SERVICE MANUAL for disassembly instructions.

For lifts exceeding 20 feet (6 meters), filling the pumping chambers with liquid will prime the pump in most cases.

For flooded conditions exceeding 10 feet (3 meters) of liquid, install a back pressure device.

Increase the inlet air pressure to the pump. Most diaphragm pumps are designed for a 1:1 pressure ratio at zero flow.

Decrease the inlet air pressure and volume to the pump as calculated on the published PERFORMANCE CURVE. The pump may be cavitating the fluid by fast cycling.

Purge the chambers through the tapped chamber vent plugs. PURGING THE CHAMBERS OF AIR CAN BE DANGEROUS! Contact Technical Services before performing this procedure. Any model with a top-ported discharge will reduce or eliminate problems with entrained air.

General: Read all safety warnings and instructions completely before installation and start-up. It is the responsibility of the purchaser to retain the manual for reference.

Pressurization: The pump is pressurized internally with air during operation. Always ensure all bolting is in good condition and that the correct bolting is reinstalled during assembly.

Toxic/Aggressive Fluids: When used for toxic or aggressive fluids, the pump should always be flushed clean prior to disassembly.

Gasketed Fasteners: Before operation, inspect all gasketed fasteners for looseness caused by gasket creep. Re-torque loose fasteners to prevent leakage.

Maintenance Safety: Before any maintenance or repair, shut off the compressed air line, bleed the pressure, and disconnect the air line from the pump. The discharge line may be pressurized and must also be bled of its pressure. Ensure all pressure is completely vented from the pump, suction, discharge, piping, and all other connections. Lock out the air supply so it cannot be started while work is being done. Wear approved eye protection and protective clothing at all times in the vicinity of the pump.

Diaphragm Rupture: In the event of a diaphragm rupture, the pumped material may enter the air end of the pump and be discharged into the atmosphere. If pumping a hazardous or toxic product, the air exhaust must be piped to an appropriate area for safe disposition.

Noise and Particles: The ALEMITE 8323 can produce airborne particles and loud noise. Always wear ear and eye protection.

First, shut off the compressed air, bleed pressure from the pump, and disconnect the air supply line.

Step 1: Using a 9/16″ wrench or socket, remove the four hex capscrews (item 12). Remove the air valve assembly and inspect the gasket (item 16) for cracks or damage, replacing it if needed.

Step 2: Disassembly of the air valve.

1. Using a 7/16″ wrench or socket, remove the eight hex capscrews (items 1-F) that fasten the end caps to the valve body.

2. Remove the two end caps (items 1-E). Inspect the two o-rings (items 1-D) on each end cap for damage or wear. Replace o-rings as needed.

3. Remove the bumpers (items 1-C). Inspect for damage or wear and replace as needed.

4. Remove the spool (part of item 1-B) from the sleeve, being careful not to scratch or damage it. Wipe the spool with a soft cloth and inspect for scratches or wear.

5. Inspect the inner diameter of the sleeve (part of item 1-B) for dirt or scratches. If needed, remove the sleeve and replace it with a new sleeve and spool set (item 1-B).

Step 3: Reassembly of the air valve.

1. Install one bumper (item 1-C) and one end cap (item 1-E) with two o-rings (items 1-D), and fasten with four hex capscrews (items 1-F) to the valve body (item 1-A).

2. From the new sleeve and spool set (item 1-B), carefully remove the spool from the sleeve. Install the six o-rings (item 1-D) into the six grooves on the sleeve.

3. Apply a light coating of grease to the o-rings before installing the sleeve into the valve body (item 1-A). Align the slots in the sleeve with the slots in the valve body.

4. Insert the spool into the sleeve, being careful not to scratch or damage it during installation.

5. Carefully insert the sleeve into the bumper and end cap (with o-rings) and fasten with the remaining hex capscrews.

6. Fasten the air valve assembly (item 1) and gasket to the pump. Connect the compressed air line to the pump. The pump is now ready for operation.

First, shut off the suction and discharge lines. Then, shut off the compressed air supply, bleed the pressure, and disconnect the air line. Drain any remaining liquid from the pump.

Step 1: Using a 1/2″ wrench or socket, remove the 16 capscrews (item 9) that fasten the manifolds (items 19 & 20) to the outer chambers (item 13).

Step 2: Using a 1/2″ wrench or socket, remove the 16 capscrews (item 10) that fasten the outer chambers (item 13), diaphragms (item 14) and intermediate (item 5) together.

Step 3: Use a 7/8″ wrench or six-point socket to remove the outer diaphragm plate assemblies (item 24), diaphragms (item 14), and inner diaphragm plates (item 23) from the diaphragm rod (item 27) by turning counterclockwise. Inspect the diaphragm for cuts, punctures, or wear. DO NOT USE A WRENCH ON THE DIAPHRAGM ROD, as flaws on the surface may damage bearings and seals.

Step 4: Push the threaded stud of one outer diaphragm plate assembly through the center of one diaphragm and one inner diaphragm plate. Install the diaphragm with the natural bulge facing away from the rod. Ensure the radius on the inner diaphragm plate is towards the diaphragm. Thread the assembly onto the diaphragm rod, leaving it loose.

Step 5: Make sure the bumper (item 6) is installed over the diaphragm rod and insert the rod into the pump. On the opposite side, pull the rod out as far as possible. Install the second bumper. Push the threaded stud of the other outer diaphragm plate assembly through the center of the other diaphragm and inner plate. Thread this assembly onto the rod. Use a 7/8″ wrench or socket to hold one outer diaphragm plate, then use a torque wrench to tighten the other outer plate to the diaphragm rod to 500 in. lbs. (56.5 Newton meters).

Step 6: Align one diaphragm with the intermediate and install the outer chamber using 8 capscrews. Tighten the opposite diaphragm plate until the holes align with the intermediate. Install the other outer chamber with its 8 capscrews. Reinstall the manifolds to the pump using the 16 capscrews. The pump is now ready to be reinstalled and returned to operation.

The overlay diaphragm (item 15) is designed to fit over the exterior of the standard diaphragm (item 14). Follow the same procedures described for the standard diaphragm for removal and installation. The only exception is to tighten the outer diaphragm plate assembly, diaphragms, and inner diaphragm plate to the diaphragm rod to 500 in. lbs. (56.5 Newton meters).

First, shut off the compressed air supply, bleed the pressure from the pump, and disconnect the air supply line.

Step 1: Using a 1/2″ wrench or socket, remove the four capscrews (item 11). Remove the air inlet cap (item 8) and air inlet gasket (item 18). The pilot valve assembly (item 4) can now be removed for inspection and service.

Step 2: Disassembly.

1. Remove the pilot valve spool (item 4-D). Wipe clean and inspect the spool and o-rings for dirt, cuts, or wear. Replace if necessary.

2. Remove the retaining ring (item 4-F) from the end of the sleeve (item 4-B) and remove the sleeve from the valve body (item 4-A). Wipe clean and inspect the sleeve and o-rings for dirt, cuts, or wear. Replace if necessary.

Step 3: Re-assembly.

1. Generously lubricate the outside diameter of the sleeve and o-rings. Carefully insert the sleeve into the valve body, being cautious not to shear any o-rings. Install the retaining ring to the sleeve.

2. Generously lubricate the outside diameter of the spool and o-rings. Carefully insert the spool into the sleeve, again being cautious not to shear any o-rings. Use BP-LS-EP-2 multipurpose grease, or equivalent.

Step 4: Re-installation.

1. Re-install the pilot valve assembly into the intermediate. Be careful to align the ends of the pilot valve stem between the plunger pins when inserting the valve.

2. Re-install the gasket, air inlet cap, and capscrews. Connect the air supply to the pump. The pump is now ready for operation.

First, shut off the compressed air supply, bleed the pressure from the pump, and disconnect the air supply line.

Step 1: See the PUMP ASSEMBLY DRAWING. Using a 1/2″ wrench or socket, remove the four capscrews (items 11), the air inlet cap (item 8), and the air inlet gasket (item 18). The pilot valve assembly (item 4) can now be removed.

Step 2: The actuator plungers (items 25) can be reached through the pilot valve cavity in the intermediate assembly (item 5). Remove the plungers (item 25) from the bushings (item 7). Inspect the installed o-ring (items 21) for cuts and/or wear, replacing if necessary. Apply a light coating of grease to each o-ring and re-install the plungers into the bushings, pushing them in as far as they will go. To remove the bushings (item 7), first remove the retaining rings (item 26) with a flat screwdriver. It is recommended that new retaining rings be installed.

Step 3: Re-install the pilot valve assembly into the intermediate assembly. Be careful to align the ends of the stem between the plungers when inserting it. Re-install the gasket (item 18), air inlet cap (item 8), and capscrews (item 11). Connect the air supply to the pump. The pump is now ready for operation.

First, shut off the suction and discharge lines. Then, shut off the compressed air supply, bleed the air pressure, and disconnect the air line. Drain any remaining fluid from the pump.

To access the check valve components, remove the manifold (item 20 or item 19 not shown) using a 1/2″ wrench or socket.

For Model 8323: Inspect the check balls (items 2) for wear, abrasion, or cuts. Inspect the check valve seats (item 29) for cuts, abrasive wear, or embedded material. The spherical surface of the balls must seat flush to the surface of the seats for the pump to operate efficiently. Replace any worn or damaged parts.

For Model 8323-A: Inspect the check balls (items 2) for wear or cuts. The check valve seats (item 29) and FEP-Encapsulated o-rings (item 33) should be inspected for cuts, abrasive wear, or damage. Replace any worn or damaged parts.

To re-assemble, the seat should fit into the counter bore of the outer chamber. The pump can then be reassembled, reconnected, and returned to operation.

When a diaphragm fails, the pumped liquid or fumes can enter the air end of the pump and be exhausted into the surrounding environment. If you are pumping hazardous or toxic materials, the exhaust air must be piped to an appropriate area for safe disposal.

If the pump is submerged, its materials of construction must be compatible with the liquid being pumped. The air exhaust must be piped above the liquid level. The piping used for the air exhaust must not be smaller than 1″ (2.54 cm) in diameter, as reducing the size will restrict air flow and reduce performance.

If the product source is at a higher level than the pump (flooded suction), pipe the exhaust higher than the product source to prevent siphoning spills.

To convert the pump to pipe the exhaust air away, simply remove the muffler. The air distribution valve (item 1) has 1″ NPT threads for piped exhaust.

Important Installation Note: It is recommended to install a flexible conductive hose or connection between the pump and any rigid plumbing to reduce stress on the molded threads of the air exhaust port. Any piping or hose connected to the exhaust port must be conductive and physically supported to prevent damage to the air distribution valve body.

* Used on Model 8323

** Used on Model 8323-A

393801-16 AIR END KIT: Seals, O-ring, Gaskets, Retaining Rings, Air Valve Assembly and Pilot Valve Assembly.

393801-22 SEAL KIT: O-Rings, Gaskets, Seals, Bumpers, Bushings, Retaining Rings

393801-6 WET END KIT used for Model 8323: Nitrile Diaphragms, Nitrile Balls, and UHMW Polyethylene Seats.

393801-9 WET END KIT used for Model 8323-A: Santoprene Diaphragms, PTFE Overlay, PTFE Balls, FEP-Encapsulated Silicone O-rings