, NC. NSTALLATON OPERATON MANTENANCE MANUAL THERMAFLO ENGNEERNG NC., inc. 1221 ROUTE PO BOX 22473639 EAST LEBANON, CHARLOTTE, NJ 08833 NC (USA) 28247 PHONE: TEL: 908-236-9570 704-940-1228 FAX: 908-236-9575 704-940-1227 E-MAL: www.thermafloengineering.com info@plateconcepts.com
Page 1 of 22 TABLE OF CONTENTS Section Page 1 NTRODUCTON 2 1.1 CONSTRUCTON 2 1.2 PLATE DESGNATONS 4 1.3 FRAME TYPES 4 2 NSTALLATON 5 2.1 AREA REQUREMENT 5 2.2 REMOVNG FROM PALLET 5 2.3 LFTNG & POSTONNG 6 2.4 PPE CONNECTONS 7 2.5 ADDTONAL CONSDERATONS 8 3 OPERATON 9 3.1 START-UP PROCEDURE 9 3.2 UNT N OPERATON 10 3.3 SHUT-DOWN PROCEDURE 10 3.4 DSASSEMBLY 11 3.5 REASSEMBLY 12 4 MANTENANCE 13 4.1 PERODC CHECKS 13 4.2 LUBRCATON 13 4.3 GASKET STORAGE 14 5 CLEANNG 14 5.1 CAUTONARY GUDELNES 14 5.2 MANUAL CLEANNG 15 5.3 BACK-FLUSHNG 15 5.4 CLEANNG-N-PLACE (CP) 15 5.5 PLATE CLEANNG TPS 16 6 REPAR PROCEDURES 17 6.1 PLATE PACK EXPANSON OR 17 REPLACEMENT 6.2 RE-GASKETNG 17 6.3 GLUNG NSTRUCTONS 18 6.4 GLUE-FREE GASKETNG 19 6.5 CLP ON GASKETNG 20 7 TROUBLESHOOTNG 21 8 STORAGE 22
Page 2 of 22 1 NTRODUCTON Thermaflo Modu-Flex series (PFHX) are custom designed to meet heating and cooling duties specified by customers in a broad range of industries and services including HVAC and comfort heating & cooling. The PFHX model and number of plates, and thus the required heat transfer area, are determined by advanced sizing programs based on the specified duty, fluids, temperature program, flow rates and hydraulic conditions for both the hot & cold circuits. 1.1 Construction The PFHX is an assembly of specially pressed plates made of a thin sheet of either stainless steel or higher alloys like titanium. Rubber gaskets made of an elastomer such as NBR (Nitrile) or EPDM provide sealing. The entire assembly is supported in a steel frame that consists of the following components: A) Fixed Cover & Movable Cover B) Top & Bottom Carrying Bars C) Tightening Bolts & Support Column Locations and descriptions of key components: Top Carrying Bar (Support Bar) Support Column Connections Movable Cover (Pressure Plate) Fixed Cover (Frame Plate) Plate Pack (Plate Bundle) Lower Carrying Bar (Guide Bar) Tightening Bolts (Compression Bolts)
Page 3 of 22 TERM FXED COVER or FRAME PLATE FRAME GASKETS LOWER CARRYNG BAR or GUDE BAR MOVABLE COVER or PRESSURE PLATE PLATES PLATE PACK or PLATE BUNDLE PROTECTVE SHROUD SUPPORT COLUMN or END SUPPORT SUPPORT PAD TGHTENNG BOLTS or COMPRESSON BOLTS TGHTEN DMENSON (TD) TOP CARRYNG BAR or SUPPORT BAR DEFNTON The fixed cover of the PFHX is where all of the connections are usually located. This allows the PFHX to be opened without removing any piping connections. The frame provides structural support and pressure containment for the plate pack. The elastomer gaskets provided on each plate direct and contain the hot and cold media through the proper channels. The lower carrying bar guides and helps align the plates. t is bolted horizontally to the fixed cover and the support column. The movable cover of the PFHX permits access to the unit for inspection and / or cleaning. t is supported and guided by the carrying bars. The metal plates are pressed with a herringbone pattern to induce a high degree of turbulence in the channels thus optimizing heat transfer efficiency. The port holes punched in the corners of each plate are equipped with elastomer gaskets. The plate pack is the assembly of gasketed metal plates between the fixed and movable covers where the heat transfer takes place through alternating hot and cold channels. The protective metal shield placed over the plate pack to provide personnel protection against fluid leakage. This column supports the carrying bars and extends to the foundation to make the PFHX totally rigid. The pad attached to the fixed cover for front support of the PFHX. These bolts are used to compress the plate pack together between the fixed and movable cover. The distance between the inside of the fixed and movable covers when the plate pack is compressed. The top carrying bar is joined horizontally to the fixed cover and the support column.
Page 4 of 22 1.2 Plate Designations Plates are labeled as Left or Right side gasketed to differentiate the direction of flow. Left Side Plate Right Side Plate A RGHT SDE PLATE S THE 180 ROTATON OF A LEFT SDE PLATE & VCE VERSA. 1.3 Frame Types Free Standing Front Support Front & Back Support N-Type B-Type P-Type
Page 5 of 22 2 NSTALLATON 2.1 nstallation Area Requirement Sufficient area around the PFHX should be allowed for maintenance and servicing. (Fig. 1) FOR PORT DAMETERS 4, ALLOW AT LEAST 40 (1000mm) OF FREE SPACE ON BOTH SDES OF THE PFHX. FOR PORT DAMETERS 6, ALLOW AT LEAST 60 (1500mm) OF FREE SPACE ON BOTH SDES OF THE PFHX. 2.2 Removing the PFHX from the Shipping Pallet Fig. 1 Area Requirement The PFHX is usually supplied on a pallet in either a facedown or upright position. Facedown (Fig. 2): Upright (Fig. 3): PFHX with studded ports are shipped facedown with the fixed cover secured to the pallet. PFHX with threaded NPT connections or with extended connections are secured to the pallet in an upright position. APPROPRATE HOSTNG EQUPMENT & STRAPS MUST BE UTLZED TO PREVENT PERSONAL NJURY. Fig. 2 Facedown Shipping Fig. 3 Upright Shipping
Page 6 of 22 2.3 Lifting and Positioning Do not use steel cables or chains. Remove all tightening devices from the pallet. Place straps around the upper bolt on each of side of the PFHX as shown in Figure 4. Use lifting holes if provided. Bring PFHX to horizontal transport to site & lower into position. Bolt PFHX to its foundation & remove straps. NEVER LFT THE PFHX BY CONNECTONS, MOVABLE COVER, UPPER CARRYNG BAR, OR PLATE PACK. Fig. 4 Lifting & Positioning LFT LARGE UNTS SLOWLY WTH THE AD OF A HEAVY DUTY SPREADER BEAM AND SUTABLE CABLES CONNECTED SECURELY TO THE LFTNG LUGS OR HOLES. X X X
Page 7 of 22 2.4 Pipe Connections There are three types of PFHX pipe connections. Studded Port SP [Standard Connection] Optional Liner Threaded - NPT [Connections 2 ] Flange Style F [Connections 3 ] Optional Studded Port Connections - SP: SP-connections are standard for all PFHX models with port diameters 1.5 and are rated according to ANS B16.5. f the SP-connection has a rubber liner, the liner will act as a flange gasket. Bolt the connecting flanges of feed and discharge lines directly to the fixed cover using the drilled and tapped holes provided for the hot & cold circuits. Tighten bolts uniformly to avoid over-tightening that could strip and damage the threads cut into the drilled holes. Threaded Pipe Connections - NPT: NPT-connections are typically used for smaller PFHX models. Make sure that NPT connections do not rotate when feed and discharge lines are fastened to them. Rotation could damage the port gaskets inside the PFHX that seal against the NPT pipe connection. Flange Style Connections - F: f F-connections are fitted to the PFHX, then a suitable gasket is required to seal the flange against adjoining piping. UNLESS OTHERWSE NDCATED, THE HOT & COLD CRCUTS SHOULD ALWAYS BE CONNECTED SO THAT FLOW S N OPPOSTE OR COUNTER-CURRENT DRECTONS.
Page 8 of 22 2.5 Additional nstallation Considerations: Connection hook-up should be according to supplier drawings. All pipe connections should be fitted with shut-off valves. All surrounding pipe-work must be adequately designed, supported and braced to avoid applying unnecessary nozzle loads to the PFHX and its connections. Feed & discharge lines must be mounted so that pipe movement due to thermal expansion does not affect the PFHX. Fittings for any installed pressure & temperature gauges must be welded to the feed & discharge piping. Connecting piping should be thoroughly flushed of all debris, weld slag, etc. prior to hook-up to the PFHX. Always install high point vents on both sides of the PFHX. Always install a strainer w/ 100 mesh screen on both sides of the PFHX. F1 F2 When carrying out electric welding, the frame cannot be made the ground connection because this may cause arcing between the PFHX plates. F4 F3 PPE SUPPORTS: VENTNG: DRANS: PUMPS: VALVES: Place supports as close to the connections as possible so that valves and piping do not apply loads to the nozzles. Upper connections, F1 & F2, must be provided with vents at the highest position possible in the piping. The PFHX must be vented immediately after start-up to prevent harmful air-locks. Bottom connections, F3 & F4, must be provided with drains at the lowest point of the piping. The pumps feeding the PFHX must be provided with regulating valves. f the maximum pressure output of the pump is greater than that of the design pressure of the PFHX, then a safety relief valve should be installed in the inlet piping. Pressure control valves should be placed at the inlet of the PFHX, never at its outlet, even if a pressure control switch is provided.
Page 9 of 22 3 OPERATON 3.1 START-UP PROCEDURE t is very important that the system to which the PFHX is connected is protected against sudden and extreme variations of temperature and pressure. The PFHX should be fully vented during start-up. t is generally recommended to start the cold circuit before the hot circuit. 1. Before initial start-up or after a long shut-down period, verify that the plate pack is compressed to the TD indicated on the certified drawing or the nameplate. 2. Before starting any pump, make sure that the pump discharge valves (the valves between the pumps & the hot and cold inlet connections of the PFHX) are completely closed. 3. Open all PFHX outlet valves (if any) completely. 4. Confirm that high point vent on cold side is open to remove air from the system. 5. Start cold circuit pump and open pump discharge valve slowly. Pump is started against closed discharge valve in order to prevent pressure shock to the PFHX. 6. Close vent when liquid starts to flow out of it. This indicates that air is out of the system and system including PFHX is flooded. 7. Repeat the same procedure for hot circuit. 8. The operating pressure should not be reached until the PFHX has reached its operating temperatures. HAMMERNG MUST BE AVODED. HAMMERNG OR MPROPER START-UP MAY SHFT AND DAMAGE GASKETS CAUSNG LEAKAGE.
Page 10 of 22 3.2 UNT N OPERATON 1. Any adjustments to flow rates should be performed gradually to maintain correct temperatures or pressure drops. 2. Thermal and hydraulic shocks to the system must be prevented. 3. Problems in maintaining performance and capacity may be caused by fouling (blockage, scale deposition, suspended solids, etc.) OR by deviations in the fluid behavior and operating conditions (flow, temperature and pressure) from design values. 4. Check for external leaks periodically. 5. As long as the PFHX is operating satisfactorily, it should be left without any interference. 3.3 SHUT-DOWN PROCEDURE Never open PFHX when it is hot. Cool PFHX to room temperature before opening to prevent loosening of the gaskets. Shut-down for a Short Period: 1. Slowly close pump discharge valve (or flow control valve) for hot circuit while maintaining full flow in the cold circuit. 2. Turn off hot circuit pump. 3. Cool down PFHX to temperature of cold medium. 4. Slowly close pump discharge valve for cold circuit. 5. Turn off cold circuit pump. 6. Close all remaining isolating valves. Shut-down for a Long Period: 1. Follow above procedures. 2. Drain hot & cold circuits. 3. Lubricate & loosen tightening bolts until plate pack length expands to max. 10% over specified TD dimension. 4. Avoid loosening the plate pack excessively to minimize risk of debris entering in between the plates. 5. Place a dark protective covering over plate pack. REMEMBER TO TGHTEN PFHX TO PROPER TD PROR TO STARTNG UP AGAN.
Page 11 of 22 3.4 DSASSEMBLY 1. Detach connections (if any) from movable cover. 2. Lubricate carrying bar and bolts. 3. Completely loosen and remove bolting designated by a white circle in the following diagram: Loosening Sequence 6 Bolt Unit 8 Bolt Unit 10 Bolt Unit 12 Bolt Unit Bolts that are removed Bolts that remain 4. Loosen remaining bolts by small increments in a clockwise order. 5. Lift bolts out when the tension is relieved. 6. Pull back movable cover and open the plate pack for inspection and cleaning. t is preferable to inspect & clean the plates one by one without removing them from the frame. 7. Dismantle the plate pack with care & remove one plate at a time. FOR EASE OF REASSEMBLY, REMEMBER TO SEQUENTALLY NUMBER PLATES COUNTNG FROM MOVABLE COVER TOWARD FXED COVER BEFORE REMOVNG THEM FROM THE FRAME. 8. To remove a plate: Tilt plate towards the movable cover until it swings free of the lower carrying bar. Carefully disengage plate from the top carrying bar & swing it from the frame. f two or more plates have stuck together, remove them as carefully as possible so that the gasket remains in the groove.
Page 12 of 22 3.5 REASSEMBLY General Guidelines: Never tighten the PFHX when it is full of liquid, under pressure, or during operation. Bolts should be tightened first by hand, then by a ratchet wrench or pneumatic tightening gun. Measure plate pack length with a ruler & check it repeatedly at all tightening bolt locations. For PFHX of any size, use a criss-cross pattern similar to the one described below when tightening. Proper positioning of Tightening Sequence: plates is indicated by 1. Push the movable cover up to the last plate. a honeycomb pattern. 2. Compress plate pack as far as possible by hand. 3. Lubricate bolt threads & install the tightening bolts. 4. Bolts should be tightened uniformly in the alternating sequence described below. T S ESSENTAL THAT THE PLATE PACK & MOVABLE COVER MOVE PARALLEL TO THE FXED COVER WHEN TGHTENNG THE PFHX. 1 Tighten bolts 2L, 4R, 4L and 2R to within 6 of TD on nameplate. TAKE N APPROX. 1 PER BOLT. Tightening Sequence - 10 Bolt Unit 2 As resistance increases, add bolts 3L and 3R to tightening sequence. The six bolts should close the pack to within 3 of TD. TAKE N APPROX. 1/2 PER BOLT. 1L 2L 1R 2R 3 Add bolts 1L, 5R, 5L, and 1R to the sequence until within 1 of the TD. TAKE N APPROX. 3/8 PER BOLT. 3L 3R 4 Tighten all bolts sequentially until required TD is reached. TAKE N APPROX. 1/4 PER BOLT TO WTHN 1/2 OF TD. THEN TAKE N APPROX. 1/8 PER BOLT TO THE TD. 4L 5L 4R 5R Do not tighten plates below the tightening dimension TD specified on the nameplate or certified drawing as this will damage the plates.
Page 13 of 22 4 MANTENANCE Regular checks of the PFHX can help reduce the extent and cost of shut-down. Maintenance of the Plate & Frame Heat Exchanger should be carried out on a routine basis on those items whose function or performance may deteriorate over time. Due to the varying nature of the services and site conditions to which the PFHX is exposed, a specific time interval for each application check-up is not practical. Thus, it is up to the user to establish a regular time schedule to suit his operating conditions. 4.1 Points to Check Periodically Fixed & Movable Covers Carrying Bars Tightening Bolts Connections Plate Pack Pressure Temperature nspect and touch up paint as necessary. Keep all surfaces clean. Check tightness of nuts and make sure threads are continuously lubricated. Check tightness of flange or pipe fittings. Check plate pack dimension (TD). nspect plates for bent or deformed edges. Check for gasket extrusion as this can indicate failed gasket adhesion or subjection of the PFHX to pressure shocks. Check for pressures higher than design or greater than the specified maximum differential. Check for temperatures higher than design. 4.2 Lubrication The tightening bolts and nuts should be lubricated often so that they can be opened easily at the time of disassembly. Keep the carrying bars greased to enable the plates to slide smoothly across the bar and avoid corrosion.
Page 14 of 22 4.3 Gasket Storage The following procedures should be utilized for storing gaskets: Gaskets should be stored loosely so that they do not crease. Sealed plastic bags are recommended for use as storage containers. Keep gaskets out of direct sunlight in a dark storage space. Gasket storage areas should not be located near sources of ozone. Gaskets should be used on a 'first in - first out' basis. Store different elastomer materials separately. 5 CLEANNG To help insure that there will be no damage to the plates or gaskets during cleaning operations, please abide by the following guidelines: 5.1 CAUTONARY GUDELNES PFHX should never be opened when hot. Plates should never be cleaned with a steel brush or steel wool. f a brush is required, use a soft, fiber-type brush. Always wear gloves and eye goggles when using cleaning products. Gaskets should always be wiped clean with a cloth before the PFHX is closed to insure that there is no particulate matter still adhering to them. t is important to use CLEAN WATER (e.g. free of salt, sulfur and high iron concentrations) when flushing or rinsing the plates. Chlorinated solutions (if used) must be of minimum concentration levels at the lowest possible temperature and the maximum exposure time should be 10 minutes. Cleaning solution should be mixed with water to the proper concentration before use and then circulated with a centrifugal pump.
Page 15 of 22 5.2 Manual Cleaning Care should be taken not to damage the gasket surface when cleaning manually. 1. Open the PFHX according to Disassembly instructions. 2. Number plates or draw a diagonal line across plates before removal from the frame. 3. Clean each plate separately with a soft brush and running water. DO NOT SPRAY HGH PRESSURE WATER DRECTLY ON THE GASKETS. 4. nspect & clean the lower portion of each plate thoroughly because this is the primary area where solid materials tend to accumulate. 5. Rinse each plate with clean water at high pressure after brushing. 6. See Plate Cleaning Tips for chemical cleaner recommendations. 7. Upon final inspection of each plate, close the PFHX & compress plate pack to TD shown on the certified drawing or nameplate. 8. Return PFHX to operation. 5.3 Back-flushing Because the Plate & Frame Heat Exchanger has many contact points to withstand high pressure differentials, particulate can build-up at these points. This problem can be greatly reduced by back-flushing on the fouled side. n some applications, the flow can be reversed on both sides in order to maintain countercurrent heat transfer and thus the PFHX is operational during this cleaning cycle. 5.4 Cleaning- in- Place (CP) Cleaning-in-place is recommended when corrosive liquids are being processed in the PFHX. Drain piping should be installed to avoid corrosion of the plates due to residual liquids left in the PFHX after an operating cycle. 1. Drain both sides of the unit. 2. Flush unit on both sides with warm water at approximately 110 F until the effluent water is clear and free of process fluid. 3. Drain the flush water from the unit and connect CP pump. See Plate Cleaning Tips for recommended cleaners.
Page 16 of 22 CP continued 4. Flow CP solution bottom to top to insure wetting of all surfaces with cleaning solution. When cleaning multiple pass units, it will be necessary to reverse flow for at least ½ the cleaning time to wet all surfaces. 5. For optimum cleaning, use the maximum flow rate of water rinse or CP solution that the CP nozzle size will allow. A CP operation will be most effective if performed on a regularly scheduled basis and before the unit is completely fouled. 6. Flush thoroughly with clean water after CP cleaning. 5.5 Plate Cleaning Tips 1. Do not use hydrochloric acids with stainless steel plates. 2. Do not use chlorine or chlorinated water to clean stainless steel, Hastelloy, ncolloy, nconel and 254SMO. 3. Water with more than 300 ppm Cl may not be used for cleaning solutions. 4. Do not use phosphoric or sulfamic acid for cleaning titanium plates. 5. Limit cleaning solution concentration to 4% in strength, with temperatures not exceeding 140 F (60 C) unless otherwise specified. 6. f brine is used as a cooling medium, completely drain the fluid and flush the unit with cold water prior to any cleaning operation. 7. Protect carrying bars and support columns in aluminum from chemicals. TYPE OF FOULNG Calcium Sulphate, Silicates Calcium Carbonate Alumina, Metal Oxides, Silt Barnacles, Mussels, Seaweed, Wood Chips Biological Growth SUGGESTED CLEANERS Citric, Nitric, Phosphoric or Sulfamic Acid 10% Nitric Acid (1 volume concentrated Nitric Acid with specific gravity 1.41 to 9 volumes of water), Oakite 131 Citric, Nitric, Phosphoric, or Sulfamic Acid (To improve cleaning, add detergent to acid.) Back Flush per cleaning-in-place procedure Sodium carbonate or sodium hydroxide
Page 17 of 22 6 REPAR PROCEDURES 6.1 Plate Pack Expansion or Replacement When replacing or installing new plates, mark & identify each new plate with similar markings (suggest adding suffix A, B, etc.) to differentiate from original plate pack. 1. Open plate pack according to Shut-down & Disassembly procedures. 2. nstall new plate(s) in the correct position as either Left or Right side gasketed plates. 3. Check all plate & gasket surfaces for cleanliness and remove any debris. 4. Re-tighten plate pack to the specified TD for the revised number of plates. 5. Verify that plate pack is properly assembled in a honeycomb pattern. 6.2 Re-Gasketing Glued Type Gaskets Step 1 Plate Removal Step 2 Plate dentification Step 3 Gasket Removal Step 4 Plate Cleaning Step 5 Plate nspection Step 6 Plate Gluing Step 7 Final Check Remove plate from PFHX. Mark plate location in plate pack. dentify gasket arrangement (start, right or left). Remove old gasket without damaging the plate. f gasket still adheres, apply heat to reverse side of plate. Clean old glue & remaining gasket from groove. Use solvent (e.g. acetone, MEK, etc.) if required. Dry plate. Zyglo test plate for cracks. Give a careful visual check. Apply a thin coat of glue into gasket groove. Roughen back side of gasket. Press gasket into groove as uniformly as possible without excess glue oozing out of the groove. Stack the plates. Keep plates pressed together for 12 hours at room temperature. For EPDM gaskets, press for 24 hours (see GLUNG NSTRUCTONS below). Remove any excess adhesive from plate with solvent. Check all sealing surfaces for particles that may cause gasket damage. Re-install plates in correct order & with all gaskets facing towards the fixed cover.
Page 18 of 22 6.3 Gluing nstructions Thermaflo recommends using chloride-free glues like Pliobond 20 or 30, Bostic 1782, 3M EC 1099 and Bond Spray 77. The choice is based on the service conditions the PFHX is designed for and the location where the re-gasketing needs to take place. We have listed the glue designations, their applications and gluing procedures in the following two tables: Non-Heat Curing Type Glue Characteristics: One component rubber based adhesive Limited temperature resistance (below 150 F) Application: General all purpose for field repairs Gluing Procedure: 1. Stir the adhesive thoroughly. 2. Roughen back side of gasket. 3. Apply a thin layer of adhesive on the back side of the gasket. 4. Allow the adhesive to dry a little. 5. Apply adhesive to the gasket groove in the plate with a brush. 6. Allow the glue to dry so that it does not feel sticky when lightly touched but is still not completely dry. 7. Place the gasket correctly into place. 8. Stack the plates so that the gaskets are in contact with the bottom of the groove. 9. After 24 hours at room temperature the glue is approximately 75% cured. 10. nspect the plates and remove any superfluous adhesive. 11. The plates can be installed in numerical order in the unit. 12. The pack can be tightened to the given TD dimension (the glue will be completely cured in 48 hours). NOTE: DRY HEAT APPLED TO THE PLATE PACK (200 F MAX) WLL REDUCE THE CURNG TME. When using commercial solvents or adhesives, follow manufacturer s instructions carefully as many may be hazardous. Glues must be chloride-free.
Page 19 of 22 Cold Heat Curing Type Glue Characteristics: Two component epoxy based adhesive High temperature resistance (up to 300 F) Application: General all purpose for field repairs Gluing Procedure: 1. Mix equal parts of the epoxy (each has a different color) in a clean tin at room temperature. 2. Stir the mixture until the color is uniform. 3. Roughen the back side of the gasket. 4. Apply a thin layer of adhesive to the gasket groove in the plate with a brush. 5. Place the gasket correctly into place. 6. Hold the gasket in place with tape. 7. Remove excess epoxy with a cloth, moisten with MEK solvent. 8. Stack the plates so that the gaskets are in contact with the bottom of the groove. 9. The adhesive should stand for 12 hours for design temperatures below 150 F and for 24 hours for design temperatures up to 300 F 10. nspect the plates. 11. nstall the plates as marked, matching the original sequence. 12. The pack can be tightened. NOTE: THE ADHESVE SHOULD BE USED WTHN TWO HOURS AFTER MXNG. 6.4 Glue-Free Gasketing: PC Snap-Trac System Certain PFHX models are available with glue-free gaskets. The PC Snap-Trac gasketing system is designed to snap into pinched portions of the gasket groove. Both the gasket and groove must be kept free of debris and oil.
Page 20 of 22 6.5 Re-Gasketing Hang-On or Clip-On Type Gaskets Step 1 Plate Removal Step 2 Plate dentification Step 3 Gasket Removal Remove the existing gasket being very careful not to damage the existing gasket seating surface. Mark plate location in plate pack. dentify gasket arrangement (start, right or left). Remove old gasket without damaging the plate. Wipe the gasket channel clean of all foreign matter. Step 4 Plate Cleaning Step 5 Plate nspection Step 6 Plate Gluing Clean channel using solvent (e.g. acetone, MEK, etc.) if required. Dry plate. Give a careful visual check. Make sure that the gasket is properly positioned in relation to the outlet holes and the direction of flow required in each plate. Begin attaching the gaskets to outside edge of the plate by slipping the prongs under the embossed groves (see sketches below). The prongs will hold the gasket securely in place and maintain proper alignment. Continue this process all the way around the perimeter of the plates. Step 7 Final Check Stack the plates together ensuring that all of the gaskets and prongs are stacked and properly aligned and that the plates are assembled correctly to insure proper countercurrent flow before tightening the plate pack.. Re-install plates in correct order & with all gaskets facing towards the fixed cover.
Page 21 of 22 7 TROUBLESHOOTNG Problem Probable Cause Corrective Action PERFORMANCE DECREASE Temperature or flow condition is less than what is indicated on the specification sheet Pressure drop much greater on start-up than what is indicated on the specification sheet Temperature program diminishes or pressure drop increases on either side LEAKAGE Leakage at start-up Leakage outside of plate pack after operation over a period of time Piping set-up for co-current flow instead of countercurrent flow Wrong assembly of plate pack Air in the system Port area blocked with piping debris Suspended particles present in fluid Air in the system Channels in plate(s) blocked Flow larger than design flow Medium physical properties differ from design data Heat transfer surface fouled Connections are interchanged or reversed Air in the system Conditions deviate from design data Plate pack not tightened sufficiently At the connections Mixing of the two streams Exposure to sudden pressure surge Gasket failure Check certified print and flow diagram for correct inlet & outlet Open PFHX & check plate assembly with flow arrangement drawing De-aerate piping / check for air lock Clean-out portal area manually Back-flush (or reverse flow) De-aerate piping / check for air lock Flush / Clean Adjust flow to specification Check fluid & properties against specification Dismantle PFHX to check for fouling Remove debris on plate surfaces Use CP cleaning if available Make sure flow is countercurrent De-aerate piping / check for air lock Adjust operating conditions Check plate pack TD & tighten to TD specified on print or name plate Check the rubber liners (if included) Check starter plate O-rings Check plates for pinholes & cracks Open & close valves slowly Check plate pack TD Replace gaskets LEAKAGE - EXCESSVE TEMPERATURE Hardened and brittle gasket with a shiny gasket face (can be crumbled with fingers) Hot side operating temperature exceeds specified temperature limits Lower hot side temperature Replace with gaskets made of a higher heat tolerant material High pressure steam throttled to a lower pressure (performance is greatly reduced) FLUD NCOMPATBLTY Swelling of gasket surface; feels tacky to touch with gaskets falling off the plate Superheated steam applied to PFHX PFHX is being used for services other than what it is designed for Possible chemical attack nstall a de-superheater in steam feed line to PFHX Consult manufacturer for design alternatives or modifications
Page 22 of 22 8 STORAGE Please use the following guidelines when storing the PFHX for any period of time: GENERAL GUDELNES: PFHX must be covered with dark plastic for protection from daylight, welding light, dust and dirt. Storage must take place indoors at temperatures around 60-70 F (15-20 C) with a maximum of 70% humidity. f indoor storage is not possible, place PFHX in a wooden case with a lining that provides protection against moisture. There should be absolutely no ozone producing equipment in the PFHX storage space. PFHX must be protected from accidental blows and similar physical damage. Do not keep organic solvents or acids in PFHX storage space. For Long-Term Storage (6+ months), follow these additional steps: Loosen the tightening bolts so that the plates and gaskets are in a relaxed state. Complete assembly information in accordance with the nstallation / O&M Manual. Before operation, the plate pack must be compressed to its original tightening dimension (TD). WARRANTY: Seller hereby warrants that the exchanger and its performance shall conform to the description and specifications contained in Seller s data sheet, provided the exchanger is properly installed, operated under normal use and service, and properly maintained. Purchaser is responsible for ascertaining that the exchanger is commissioned and placed in operation in accordance with industry standards, and is operated according to design conditions specified, and the fluids to be processed conform to the physical property data specified. Seller warrants the material quality and workmanship of the exchanger for a period of 12 months after the exchanger is placed in operation, not to exceed 18 months from date of shipment. Seller assumes no responsibility for deterioration of the equipment due to corrosion, erosion, or flow induced damage such as, but not limited to waterhammer, pressure surges or vibration, fatigue or for fouling, normal wear and tear, maintenance problems or any other causes not specifically covered under the foregoing warranty. The sole remedy of Buyer with respect to any part not conforming to Seller s warranty shall be the repair or, at Seller s option, replacement of any defective part at the point of manufacture. Buyer assumes all costs of removal, shipping and reinstallation, provided that immediate written notice of the defect has been given to Seller. Seller shall not be liable for any other expenses incurred because of failure of any part to meet Seller s warranty, nor for any special, indirect or consequential damages. Material returned to Seller s factory without its written consent will not be accepted. No back charges will be honored without Seller s advance approval of the work to be performed. Seller s liability on any claim of any kind, including negligence, for any loss or damage arising out of, connected with or resulting from this transaction, or the design, manufacture, sale, delivery, resale, installation, technical direction of installation, inspection, repair, operation, or use of any equipment covered by or furnished hereunder shall in no case exceed the price paid by Buyer for the equipment. Seller also disclaims all liability, whether in contract, tort, warranty, or otherwise, to any party other than the Buyer.