复制成功
  • 图案背景
  • 纯色背景

笔记

  • 2019-11-16
    为大人带来形象的羊生肖故事来历 为孩子带去快乐的生肖图画故事阅读
    谈谈怎样学好数学_苏步青-中学生文库
bookoneyee..

上传于:2016-03-25

粉丝量:0

西藏11选5_[官网首页]该文档贡献者很忙,什么也没留下。



SUCTION

下载积分:3000

内容提示: MI - 126-Apr-06SUCTION & LIQUID LINE SIZING TYLER SPEC GUIDESUCTION & LIQUID LINE SIZING CHARTSUSING LINE SIZING CHARTSBasisThese line sizing charts are based on a suction pressure drop equivalent to a 2°F change in saturationpressure and liquid line pressure drop of 5 psi. For R-404A Low Temperature 1 psi; for R-404A and R-22 Medium Temperature 2 psi is used. This is the maximum allowable pressure drop for the entirepiping run regardless if it is 50' or 250'. The advantage of the graphic representatio...

文档格式:PDF| 浏览次数:6| 上传日期:2016-03-25 03:53:51| 文档星级:
MI - 126-Apr-06SUCTION & LIQUID LINE SIZING TYLER SPEC GUIDESUCTION & LIQUID LINE SIZING CHARTSUSING LINE SIZING CHARTSBasisThese line sizing charts are based on a suction pressure drop equivalent to a 2°F change in saturationpressure and liquid line pressure drop of 5 psi. For R-404A Low Temperature 1 psi; for R-404A and R-22 Medium Temperature 2 psi is used. This is the maximum allowable pressure drop for the entirepiping run regardless if it is 50' or 250'. The advantage of the graphic representation of this information is to show just how close to full capacity a particular selection is. This is true for both thecondensing unit capacities on the individual specification sheets or the separate suction line sizingcharts. When the suction line graphs are arranged according to temperature the relationship of temperature and line sizing become readily apparent. The lower the temperature, the larger the linerequired for the same heat load.Equivalent FeetNotice the phrase "Equivalent Feet" (applies to meters as well). Fittings added to a refrigerant line induce an added pressure drop in the line. Theadded pressure drop is accounted for by adding extra length (see chart onpage MI-11) to the piping run which will equal the same pressure drop produced by the fittings. In order to determine the equivalent footage, add the actual length of the piping run and the equivalent footage assigned foreach particular fitting. Plot the intersection of the horizontal BTUH line with the vertical equivalent footage line. The area in which the plotted point falls in the recommended line size.Liquid Line SizingDue to the lack of space, the specification sheets have just one column for a liquid line size. The line sizes given on the specification sheets are based on a 5 pound pressure drop for the entire piping run, from 50' to 250'.Example: A 25,000 BTUH load will require a 3/8" line for 100 equivalent feet (Point A). At 150 equivalent feet, a 1/2" line would be required for the same load (Point B).Liquid Line Sizing MI - 225-Apr-06SUCTION & LIQUID LINE SIZING TYLER SPEC GUIDESizing Suction & Liquid Sub-Feed Line ProperlyNOTE: Liquid & suction line lengths over 300 equivalent feet are discouraged by TYLER. Contact Applications Engineering for recommendations exceeding 300 equivalent feet!CASE-TO-CASE SUCTION LINE SUB-FEED BRANCH LINE SIZINGFT 6 8 12 16 20 24 28 32 36 40 44 48 52 56R-404A 1/2” 7/8” 7/8” 7/8” 7/8” 1-1/8” 1-1/8” 1-1/8” 1-1/8” 1-1/8” 1-1/8” 1-1/8” 1-1/8” 1-1/8”Suction Line SizingThe line sizing charts on each case specification sheet can be used to size the subfeed branch lines.When the line serves one case. select the size specified for 50 equivalent feet for the 8’ or 12’ case. This may be as small as 5/8” (example service meat cases), or as large as 1-3/8” (examplemulti-shelf ice cream cases). Select each suceeding step on the basis of the number of feet of casebeing served by that portion of the suction line.Liquid Line SizingUse the liquid line size chart on page MI-10 to determine the appropriate size in the same manner as forsuction lines.Exception - In the case of gas defrost, follow the special instructions on page MI-6 making and sizing a liquid line manifold at the case.Low temp suction lines and all liquid lines must be insulated in all Nature’s Cooling and Enviroguard applications! Horizontal suction lines should slope 1/2” per 10’ toward the compressor to aid in good oil return. MI - 326-Apr-06SUCTION & LIQUID LINE SIZING TYLER SPEC GUIDEREFRIGERATION PIPINGSuccessful Installation of a Refrigeration System is Dependent Upon:1. Good piping practices - with properly sized and installed lines as described in this section.2. Cleanliness of all refrigeration piping is of the utmost importance in the installation procedure.The use of gaseous nitrogen or carbon dioxide flowing at low pressure through the lines while they arebeing welded is necessary to assure relative freedom from oxides and scale which can clog the smallports on pilot operated valves and other valves in this system.Some Possible Consequences of Poor Piping:• Increased oil requirements.• Decreased operating efficiency and loss of capacity.• Increased chances of fouling vital components.• Failed compressors.When NC-2, NC-3 or Enviroguard is employed, ALL LIQUID LINES to and from the parallel rack (all the way from the building entrance to the fixtures) MUST BE INSULATE! Allowing subcooled liquid towarm in the lines cancels the energy saving advantage of subcooling the liquid and may even cause liquid to “flash”. Flashing occurs when liquid converts to gas before reaching the expansion valve; this will cause erratic valve feed and subsequent loss of refrigeration.ALL LOW TEMP SUCTION LINES MUST BE INSULATED in order to assure cool suction gas to the compressor. Cool gas is necessary to aid in cooling the motor windings (Head cooling fans help andsometimes are required by the compressor manufacturer). Compressor motor failure can result if thesuction gas from fixtures warms too much on its way to the compressor.WITH GAS DEFROST, INSULATION ON THE SUCTION LINE helps maintain the temperature of the hot gas flowing to the cases during defrost.Insulation on suction and liquid lines helps make the whole system more efficient.Insulate - it pays!The purpose of this section is to stress some of the more important aspects of piping, and areas in which difficulties are most likely to occur. This information is general, and cannot allow for all the possible factors in a given installation which can accumulate to make it less than acceptable. Page MI-? on pressure drop emphasizes the importance of properly designing the piping system.MaterialsUse only clean, dry, sealed refrigeration grade copper tubing. Make copper to copper joints with phos-copper alloy or equal. Make joints of dissimilar metals of 35% silver solder. To prevent contamination of the line internally, limit the soldering paste or flux to the minimum required. Flux the male portion of the connection, never the female. MI - 425-Apr-06SUCTION & LIQUID LINE SIZING TYLER SPEC GUIDEPiping should be purged with dry nitrogen or carbon dioxide during the brazing process. This will pre-vent formation of copper oxide and scale inside the piping which can easily clog the small ports on pilotoperated and other valves in the system.CAUTIONPressure regulators must be used with nitrogen or carbon dioxide.Service ValvesField installed ball type service valves ARE RECOMMENDED TO FACILITATE SERVICING between themachine rack, the remote condenser, and the heat recovery coil.Use long radius elbows rather than short radius elbows. Less pressure drop and greater strength make the long radius elbows better for the system. This is particularly important on discharge hot gaslines for strength, and suction lines for reduced pressure drop.Vibration Isolation and Piping SupportPiping must be properly supported to minimize line vibration. Vibration is transmitted to the piping by movement of the compressor and pressure pulsations of the refrigerant as it is pushed through the piping.Insufficient and improper supporting of tubing can cause excessive line vibration resulting in:• Excessive noise.• Noise transmission to other parts of building.• Vibration transmission of floors, walls, etc.• Vibration transmission back to compressor and other attached components.• Decreased life of all attached components.• Line breakage.Guidelines For Good Piping1. A STRAIGHT RUN OF PIPING, must be supported at each end. Longer runs will require additionalsupports along the length; usually these are not more than 8’ intervals, depending on tubing sizeand situation. Clamps should be properly anchored and rubber grommets installed between the piping and clamp to prevent line chafing. MI - 526-Apr-06SUCTION & LIQUID LINE SIZING TYLER SPEC GUIDESupporting Corners2. CORNERS MUST BE SUPPORTED and cannot be left free to pivot around the A-B axis as shown above.Don’t Overdo It!3. DON’T OVER SUPPORT PIPING when it is attached to the compressor rack. It must be free to float without stress.4. DON’T USE SHORT RADIUS ELBOWS: They can have excessive internal stress which can lead to failure.5. CHECK ALL PIPING AFTER THE SYSTEM HAS BEEN PLACED IN OPERATION: Excessive vibrationmust be corrected as soon as possible. Extra supports are cheap when compared to the potentialrefrigerant loss caused from failed piping.PROPER LINE SIZING IS THE RESPONSIBILITY OF THE INSTALLING CONTRACTOR! ApplicationsDepartment recommendations are listed on the System Summary Sheet furnished (if requested) with the job. Also, refer to the line sizing charts in these instructions. Horizontal suction lines should slope 1/2” per 10’ toward the compressor to aid in good oil return! MI - 625-Apr-06SUCTION & LIQUID LINE SIZING TYLER SPEC GUIDEGas Defrost Liquid LinesBranch LinesLiquid lines to the cases should be branched off the bottom of the header. This ensures a full coulmn of liquid to the expansion valve. A branch line from the header to an individual case should not be over3’ long and must have a 3” expansion loop incorporated.Don’t Cross Pipe SystemsDo not run suction or liquid lines through cases that are part of a separate system, especially if either has gas defrost. If there is no way to avoid this, insulate the piping for the portion that runs through the other cases.Allow For ExpansionThe temperature variations of refrigeration and defrost cycles cause piping to expand and contract. Theexpansion of piping must be taken into consideration, otherwise a piping failure will result. The followingare typical expansion rates for copper tubing:-40°F to -100°F = 2.5” per 100 feet of run (ultra low temp)0°F to -40°F = 2” per 100 feet of run (low temp)0°F to + 40°F = 1.5” per 100 feet of run (medium temp)+ 30°F to + 50°F = 1” per 100 feet of run (high temp) Expansion loops are designed to provide a definate amount of travel. Placing the loop in the middle of a piping run will allow for maximum pipe expansion with the minimal amount of stress on the loop. Don’t use 45 degree elbows for loop construction because they will not allow the lines to flex. Refer to the charts on the next page for expansion loop lengths. Suction and liquid lines cannot be joinedtogether or be allowed to touch. Pipe hangers must not restrict the expansion and contraction of piping. Insulation on suction and liquid lines makes the whole system more efficient! Insulate - it pays! MI - 726-Apr-06SUCTION & LIQUID LINE SIZING TYLER SPEC GUIDEExpansion Loop SizingChart #1 is to be used for A, B and C type loops.Chart #2 gives the total length of the expansion joint (L) along the outer surface.Example: Given a 200 foot run of 1-3/8” medium temp piping; there will be a linear expansion of 3” tocompensate for (medium temp 1.5” per 100 feet). Pipe diameter has no affect on the amount of linearexpansion but is needed for determining the size of the expansion loop. Find the 3” column at the top ofChart #1 and go down until it crosses the 1-3/8” row. The X dimension is 24”. If using type A loop, it willbe 24”; 48” for type B; and 72” for type C.TUBE OD ‘X’ LENGTH - (IN INCHES) FOR LINEAR EXPANSION OF: 1/2” 1” 1-1/2” 2” 2-1/2” 3” 4” 5” 6” 7”7/8” 8” 11” 13” 15” 17” 19” 22” 24” 27” 29”1-1/8” 9” 12” 15” 17” 20” 21” 25” 28” 30” 33”1-3/8” 10” 14” 17” 19” 22” 24” 27” 31” 34” 36”1-5/8” 10” 15” 18” 21” 24” 26” 30” 33” 37” 39”2-1/8” 12” 17” 21” 24” 27” 30” 34” 38” 42” 45”2-5/8” 13” 19” 23” 27” 30” 33” 38” 42” 46” 50”3-1/8” 15” 21” 25” 29” 33” 36” 41” 46” 51” 55”4-1/8” 17” 24” 29” 34” 38” 41” 48” 53” 58” 63”5-1/8” 19” 26” 32” 37” 42” 46” 53” 59” 65” 71”6-1/8” 20” 29” 35” 41” 46” 50” 58” 65” 71” 77”TUBE OD ‘X’ LENGTH - (IN INCHES) FOR LINEAR EXPANSION OF: 1/2” 1” 1-1/2” 2” 2-1/2” 3” 4” 5” 6” 7”7/8” 24” 34” 42” 49” 54” 60” 69” 77” 84” 91”1-1/8” 28” 39” 48” 55” 62” 68” 78” 87” 96” 104”1-3/8” 30” 43” 53” 61” 68” 75” 86” 97” 106” 114”1-5/8” 33” 47” 58” 66” 74” 81” 94” 105” 115” 124”2-1/8” 38” 54” 66” 76” 85” 93” 108” 120” 132” 142”2-5/8” 42” 60” 73” 85” 95” 104” 120” 134” 147” 158”3-1/8” 46” 65” 80” 92” 103” 113” 131” 146” 160” 173”4-1/8” 53” 75” 92” 106” 119” 130” 150” 168” 184” 198”5-1/8” 59” 84” 102” 118” 132” 147” 167” 187” 205” 224”6-1/8” 65” 91” 112” 129” 145” 158” 183” 204” 224” 242”Chart #1Chart #2 MI - 825-Apr-06SUCTION & LIQUID LINE SIZING TYLER SPEC GUIDESuction Line Riser Recommendations1. Risers which can be Installed without a TrapSuction line sizing is based on a design pressure drop whichrelates to the velocity of the gasses moving through the line.Acceptable velocities for horizontal suction lines (with proper1/2” slope per 10’ run) range from 500’ to more than 1500’ per minute. A properly sized line at the low range of its capacity will have a low velocity and one at full capacity will have velocities exceeding 1500 fpm. A specified minimum velocity is required to keep oil moving along with the gas whenthe pipe is vertical. The charts on the next page shows the size selection which will assure oil return up a riser. This sizemay be the same as the horizontal suction line selection or itmay be one size smaller. If the selection point on the chart isclose to the dividing line between sizes, use the smaller size.The reducer fitting must be placed after the elbow. Long elbows can be used to make the trap, or a P-trap can be used.Do not use short elbows.2. Risers which Require a P-TrapLow temperature systems must be designed knowing that oil is more difficult to move as the temperature is lowered. Therefrigerant gas also has a lower capacity to mix with the oil. Atrap will allow oil to accumulate, reducing the cross section ofthe pipe and thereby increase the velocity of the gas. Thisincreased velocity picks up the oil. The velocity chart is to beused to determine if the horizontal line size has sufficient velocity in the vertical position to carry the oil along. Generally,the riser will have to be reduced one size.3. Risers Requiring Use of Two TrapsThe use of two traps is necessary on long risers for the collection of oil during an off cycle. One trap would not be large enough to contain all coating a riser over 16’, and could result in an oil slugdelivered to the compressor system.Supporting Lines: Properly supprting the lines suspended from a wall or ceiling is very important. Line supports should isolate the lines from contact with metal. When gas defrost is used, consideration should be given to rolling or sliding supports which allow free expansion and contraction. These supports would be used in conjunction with expansion loops described on page MI-7.MAXIMUM RECOMMENDED SPACING BETWEEN SUPPORTS FOR COPPER TUBINGO.D. Line Size (In.) Max. Span (Ft.) O.D. Line Size (In.) Max. Span (Ft.)5/8” 5’ 3-1/8” 12’1-1/8” 7’ 3-5/8” 13’1-5/8” 9’ 4-1/8” 14’2-1/8” 10’ - - - - - - MI - 926-Apr-06SUCTION & LIQUID LINE SIZING TYLER SPEC GUIDEVertical Riser Suction Line Size ChartsProper line sizing is very important. When sizing for a suction line riser, use the proper chart. Thesecharts are based on maintaining minimum velocities in the risers. This will assure that the oil mixed with the refrigerant will return to the compressor. Improper line sizing could cause less than optimumperformance or pose the possibility of compressor damage due to oil failure.Suction line sizing charts apply to horizontal runs only. DO NOT use them for sizing vertical runs.Liquid line sizing charts can be used for both horizontal and vertical runs.CAUTIONWhen in doubt about oil return (due to a point being near a line), use the smaller size line.Any sizing of riser or any other suction line, or device, must be considered in view of the total system.The addition of any suction line pressure drop must be ignored.If suction”P-traps” are used, it is recommended that they be sized according to the horizontal line sizing.IMPORTANT!Do not arbitrarily reduce vertical risers without consulting these charts. Unnecessary vertical suction line reduction can cause excessive pressure drop, resulting in loss of system capacity.R-22 R-404A MI - 1025-Apr-06SUCTION & LIQUID LINE SIZING TYLER SPEC GUIDELine Sizing GuidelinesMinimum Horizontal Suction Velocity = one half of Minimum Riser Velocity.Maximum Pressure DropR-22MT = 2.21 R-22LT = 1.15 R-404A = 2.46 R-404A = 1.33NOTE: Use R-404A information for R-504 & R-507R-22 & R-404A Liquid Line Sizing ChartMINIMUM RISER VELOCITYR-22MT R-22LT R-404AMT R-404ALT1/2” 560 850 440 6605/8” 630 950 490 7407/8” 750 1130 590 8901-1/8” 860 1300 670 10101-3/8” 960 1440 750 11201-5/8” 1040 1570 810 12302-1/8” 1200 1810 930 14102-5/8” 1330 2010 1040 1570MINIMUM HORIZONTAL SUCTION VELOCITYR-22MT R-22LT R-404AMT R-404ALT1/2” 280 425 220 3305/8” 315 475 245 3707/8” 375 565 295 4451-1/8” 430 650 335 5051-3/8” 480 720 375 5601-5/8” 520 785 405 6152-1/8” 600 905 465 7052-5/8” 665 1005 520 785 MI - 1126-Apr-06SUCTION & LIQUID LINE SIZING TYLER SPEC GUIDEUSING SUCTION LINE SIZING CHARTS CORRECTLYSuction Line Sizing ChartsThe Suction Line Sizing charts include R-404A and R-22 suction temperatures, and lengths to 300 equivalent feet.* These charts are based on DuPont data and extensive field experience. The advantage of the graph presentation of information is to show just how close to full capacity a particular selection is. The suction line graphs are arranged according to temperature, and the relationship of temperature and line size becomes readily apparent. The lower the temperature, the larger the line for the same heat load.*To determine the “Equivalent Feet” (or Meters), add the length of the pipe and the equivalent footage assigned for each particular fitting. See chart below.Find the Proper ChartFind the proper chart based on refrigerant and suction temp. Simply match BTUH load on the horizontal lines with equivalent feet on the vertical line. The point formed by the intersection will indicate the propersize unless it is a dark area. Selections falling inthe dark areas of the charts show that the gas velocity is too slow to assure proper oil return,even with properly sloped lines. Reducing the line one size will increasevelocity and pressure drop. Added pressure drop will require greater refrigeration capacity. Be sure the system can handle the added load. See the vertical riser charts for proper sizing of vertical suction lines onpage MI-10.Step SizingStep sizing is suggested for selections falling in the first half of a size range. Pipe one size smaller (than the indicated run) can be used for 50’ of the run closest to the cases when the entire run is 100 equivalent feet or more. To show this principle, one size range on each suction chart has been bisected by a dotted line to indicate the “First Half-Step Size”and the “2nd Half - Full Size”. The purpose of step sizing is to assure better oil return out of the evaporators.Example: Given a 50,000 BTUH load with R-404A at 10°F Suction Temp and 150 Equivalent ft. of line, a 1-5/8” line is required. Since the selection point is in the first half of the range 50’ equivalent feet may be sized 1-3/8” usually applied to the first 50’ closest to the evaporators, but any 1-3/8” vertical riser height should be subtracted from the 50’ step sizing.EQUIVALENT LENGTH OF PIPE FOR FITTINGS & VALVES (FEET)Line Size O.D. Global Valve Angle Valve 90° Elbow 45° Elbow Tee, Sight Glass T-Branch1/2 9 5 0.9 0.4 0.6 2.05/8 12 6 1.0 0.5 0.8 2.57/8 15 8 1.5 0.7 1.0 3.51-1/8 22 12 1.8 0.9 1.5 4.51-3/8 35 17 2.8 1.4 2.0 7.02-1/8 45 22 3.9 1.8 3.0 10.02-5/8 51 26 4.6 2.2 3.5 12.03-1/8 65 34 5.5 2.7 4.5 15.03-5/8 80 40 6.5 3.0 5.0 17.0 MI - 1225-Apr-06SUCTION & LIQUID LINE SIZING TYLER SPEC GUIDER-22 Suction Line SizingStep SizingStep sizing is suggested for selection in the first half of a size range. Pipe ine size smaller can be used in the 50’ closest to the cases when the entire run is 100’ or more. Selections falling in the BLACK AREAS of the chart show that the gas velocity is below 750 fpm, which is too slow to assureproper oil return. Reducing one size will assure good oil return by increasing velocity, but the addedpressure drop will require greater refrigeration capacity. Be sure the compressor selection is adequate.NOTE:All horizontal suction lines should be sloped 12” per 10’ toward the compressor.See vertical riser charts for proper vertical suction line sizing. MI - 1326-Apr-06SUCTION & LIQUID LINE SIZING TYLER SPEC GUIDER-404A Suction Line SizingStep SizingStep sizing is suggested for selection in the first half of a size range. Pipe ine size smaller can be used in the 50’ closest to the cases when the entire run is 100’ or more. Selections falling in the BLACK AREAS of the chart show that the gas velocity is below 500 fpm, which is too slow to assureproper oil return. Reducing one size will assure good oil return by increasing velocity, but the addedpressure drop will require greater refrigeration capacity. Be sure the compressor selection is adequate.NOTE:All horizontal suction lines should be sloped 12” per 10’ toward the compressor.See vertical riser charts for proper vertical suction line sizing. MI - 1425-Apr-06SUCTION & LIQUID LINE SIZING TYLER SPEC GUIDEAvoiding Excessive Pressure DropPressure drop and resultant capacity losses are becoming more common with the increased use or EPRvalves, suction line filters, accumulators and suction manifolds on parallel systems. Each device standson its own individual merit by contributing to case or system performance. But when all the resultantpressure drops are added, the end result is lower overall system performance. The symptoms may leadone to believe that the system is undersized, but a thorough check using a differential pressure gaugewill very likely show where the real trouble lies.Some Pressure Drop Built InIn general, most manufacturers rate their equipment by allowing for approximately two pounds pressuredrop in the suction line between the evaporator to the compressor. Pressure drop built into the evapora-tor is usually considered by the designer and can frequently be larger than two pounds. This is to pro-vide refrigerant velocities high enough to ensure good oil movement even in the coldest parts of therefrigeration system.Avoiding Excessive Loss of Capacity1. Size liquid and suction lines by accurately figuring the proper equivalent length.EQUIVALELNT LENGTH = ACTUAL PIPING + LENGTH EQUIVALENCE FOR FITTINGS AND COMPONENTSUse the equivalent length chart located on page MI-11 to determine the appropriate length for the fittings.2. If possible, avoid high pressure drop components, such as various types of control valves,manifolds, tees, accumulators and filters. These devices should only be used, after all the factors have been considered. The disadvantages must be outweighed by the advantagesof combining systems, paralleling compressor, obtaining better case temperature control, protecting the compressors and/or safeguarding the system.3. If suction line filters are to be used, size them properly. Use a filter which is the same as main line size or one size over the suction service valve (whichever is larger).When Losses Are Not Made UpWhen pressure drop losses are not properly compensated for, an increase in case entering air temperature can be expected. This will be particularly noticeable when condensing unit is operating at its design ambient condition (90°F or 100°F).The following approximations can be made:Low Temp Case; each 10% increase (2# P.D.) raises entering air temp about 3°F.Medium Temp Case; each 10% increase raises entering air temp about 2°F. MI - 1526-Apr-06SUCTION & LIQUID LINE SIZING TYLER SPEC GUIDEHIGH SIDE FIELD PIPINGObserve piping run limits for best performance.• Maximum 50 equivalent piping feet to Remote Condenser.• Maximum 100 equivalent piping feet to Heat Recovery Coil.• Maximum 200 equivalent piping feet total for entire circuit.• Line size between remote condenser and Heat Recovery coil must be the same size as the discharge line.Installation NoticeRemote condensers must be mounted enough in relation to the parallel rack so that the liquid drain on the condenser is at least 3’ higher that the liquid return inlet on the receiver. This is necessary toensure free draining. The schematics below show which items need to be installed as field piping. Allitems above the broken line are considered part of the field piping and are shipped loose. A detaileddescription can be found in the “Parallel Compressor & Envoroguard Installation & Service Manual”.All the components shown in the field piping diagram should be installed. If a heat recovery coil is used, 3 check valves must be installed as shown in the diagram. One is placed in the normal flow piping to the condenser and the other two at the inlet and outlet of the HR coil. An optional IPR valve for the HR coil will also need to be field installed on the coil, for NC-2 only. Isolation ball valves are recommended for the system and can be ordered as optional equipment.Schematics Are Representative Only MI - 1625-Apr-06SUCTION & LIQUID LINE SIZING TYLER SPEC GUIDEDischarge to Remote Condenser & Heat Recovery Line SizingRecommended Liquid Line Sizing (Condenser to Receiver or Liquid Line Manifold)R-22 R-404A R-22 R-404ACAPACITY EQUIVALENT LENGTH CAPACITY EQUIVALENT LENGTHBTUH 50’ 100’ 50’ 100’ BTUH 50’ 100’ 50’ 100’6,000 3/8 1/2 1/2 1/2 75,000 7/8 1-1/8 1-1/8 1-1/812,000 1/2 1/2 5/8 5/8 100,000 1-1/8 1-1/8 1-1/8 1-3/818,000 5/8 5/8 5/8 7/8 150,000 1-1/8 1-3/8 1-3/8 1-3/824,000 5/8 7/8 7/8 7/8 200,000 1-3/8 1-3/8 1-3/8 1-5/836,000 7/8 7/8 7/8 7/8 300,000 1-3/8 1-5/8 1-5/8 2-1/848,000 7/8 7/8 7/8 1-1/8 400,000 1-5/8 2-1/8 2-1/8 2-1/860,000 7/8 1-1/8 1-1/8 1-1/8 500,000 2-1/8 2-1/8 2-1/8 2-1/8R-22 R-404ACAPACITY RECEIVER TO RECEIVER TOBTUH CONDENSER TO EVAPORATOR CONDENSER TO EVAPORATORRECEIVER 50’ 100’ RECEIVER 50’ 100’6,000 3/8 1/4 3/8 3/8 1/4 3/812,000 1/2 3/8 3/8 1/2 3/8 1/218,000 1/2 3/8 3/8 5/8 1/2 1/224,000 5/8 3/8 1/2 5/8 1/2 5/836,000 5/8 1/2 1/2 7/8 1/2 5/848,000 7/8 1/2 5/8 7/8 5/8 5/860,000 7/8 1/2 5/8 7/8 5/8 7/875,000 7/8 1/2 5/8 7/8 5/8 7/8100,000 7/8 5/8 7/8 1-1/8 7/8 7/8150,000 1-1/8 7/8 7/8 1-3/8 7/8 7/8200,000 1-1/8 7/8 7/8 1-3/8 1-1/8 1-1/8300,000 1-3/8 1-1/8 1-1/8 1-5/8 1-3/8 1-3/8400,000 1-5/8 1-1/8 1-1/8 1-5/8 1-3/8 1-3/8500,000 1-5/8 1-1/8 1-3/8 2-1/8 1-3/8 1-3/8 MI - 1726-Apr-06SUCTION & LIQUID LINE SIZING TYLER SPEC GUIDEPiping Procedures for Air Cooled CondensersWhen installing the condenser thermal expansion , it can be compensated for by an inverted piping configuration as shown in Figure 1 on page MI-18. This arrangement will act as an expansion loop for the pipe. All piping should also be run at various offset angles to help compensate for thermalexpansion, (see View A).Figure 1 shows a view of a desirable inlet piping configuration. The piping out of the roof chase (if used) should angle from a vertical to ahorizontal. This horizontal run should be supported from below. (Allpipes must be individually clamped to the support to help minimizevibration). The piping should then angle upwrds at 90 degrees. Thissection of piping should also be supported to minimize longitudinalvibrations.From this point the piping will be redirected in the horizontal directiononce again. This horizontal run should use offset piping to where it will need to be attached to the condenser. The 90 degree downwardredirection completes the inverted piping configuration.In all cases try to minimize the “X” and “L” dimensions in your pipingruns. In the case of “X”; the longer the unsupported horizontal length,the greater the likelihood of static stresses and vibration being placedon the condenser tube sheet.Outlet piping does not require the inverted configuration, but shouldotherwise be braced and supported in the same manner as statedabove.Vibration Isolation & Piping SupportPiping must be properly supported to minimize line vibration. Vibration is transmitted to the piping by movement of the compressor and pressure pulsations of the refrigerant as it is pushed through the piping. Insufficient and improper supporting of tubing can cause excessive line vibration resulting in:• Excessive noise.• Noise transmission to other parts of building.• Vibration transmission of floors, walls, etc.• Decreased life of all attached components.• Line breakage.A straight run of piping must be supported at each end. Longer runs require additional supports alongthe length, (usually not more than 8 foot intervals) depending on tubing size and situation. Clampsshould be properly anchored and rubber grommets installed between the piping and clamp to preventline clafing.NOTEA platform should be placed over any piping, to or from the condenser, that is likely to be stepped on. Most probable spots for this would be near the condenser shell or roof hatch. MI - 1825-Apr-06SUCTION & LIQUID LINE SIZING TYLER SPEC GUIDEMaterialsUse only clean, dry, selaed refrigeration grade copper tubing. Make copper to copper joints with phos-copper alloy or equal. Make joints of dissimilar metals of 35% silver solder. To prevent contamination of the line internally, limit the soldering paste or flux to the minimum required. Flux only the male portion of the connection, never the female portion.Piping should be purged with dry nitrogen or carbon dioxide during the brazing process. This prevents formation of copper oxide and scale inside the piping which can easily clog the small ports on pilot operated and other valves in the system. CAUTIONPressure regulators must always be used with nitrogen or carbon dioxide.Service ValvesField installed ball type service valves are recommended to facilitate servicing between the machine rack, the remote condenser and the heat recovery coil.Use long radius elbows rather than short elbows. Less pressure drop and greater trength make the long radius elbows better for the system.Thermal ExpansionThermal expansion and construction cause piping systems to move. When installing piping to a condenser, this movement must be compensated for to prevent damage to the installed equipment. This motion can be accommodated by using the natural flexibility of the piping system during layout, by designing expansion loops, using expansion joints or the employment of fittings. The method selected depends on space, cost, serviceability and maintenance requirements. Thermal expansion and construction should be provided for by the use of piping bends, elbows, offsets or changes in direction of the piping run. MI - 1926-Apr-06SUCTION & LIQUID LINE SIZING TYLER SPEC GUIDERECOMMENDED CASE TEMPERATURE & DEFROST CONTROL SETTINGSDisch. Defrost Htr. EPR Defrost ControlCase / Models Air Amps Settings Per Day, Fail-safe, Term. Temp.Alpine/Advantage/Alegro Temp. 6’ 8’ 12’ R-22 R-404A Electric Time Off GasLF5 -28° 4.5 1 --- --- 6 12 2 @ 36/50° ----- 2 @ 15/55°NCSX, NCSGX -25° --- 13.8 20.6 3 8 1 @ 36/50° ----- 1 @ 25-30/55°NCN(G)X, NCBX (2) -25° --- 13.8 20.6 3 8 1 @ 36/50° ----- 1 @ 25-30/55°NCEX -25° 8.6 --- --- 3 8 1 @ 36/50° ----- 1 @ 25-30/55°NCJ CX, NCJ GCX -25° --- 21.6 34.6 3 8 1 @ 36/50° ----- 1 @ 25-30/55°NCJ ECX, NCJ GECX -25° 7.8 --- --- 3 8 1 @ 36/50° ----- 1 @ 25-30/55°NTJ CX, NTJ GCX -25°/ --- 21.6 34.6 3/ 8/ 1 @ 36/50°/ ----- 1 @ 25-30/55°/(DUAL TEMP) -15° 7 14 1 @ 60/50° ----- 2-3 @ 20-25/55°NCWX -25° --- 13.8 20.6 3 8 1 @ 46/50° ----- 1 @ 25-30/55°LF5 -20° 4.5 1 --- --- 10 17 2 @ 36/50° ----- 2 @ 15/55°LFSC5 -19° 8.7 1 --- --- --- --- ----- 2 @ 36 -----NMF, NMFG -15° 6.5 6.9 10.3 7 14 1 @ 60/50° ----- 2 @ 16-20/55°NFX, NFSX, NFSGX -15° --- 6.9 10.3 7 14 1 @ 60/50° ----- 2-3 @ 20-25/55°NFN(G)X, NFB(G)X (2) -15° --- 6.6 10.3 7 14 1 @ 60/50° ----- 2-3 @ 20-25/55°NFEX, NFEGX -15° 8.6 --- --- 7 14 1 @ 60/50° ----- 2-3 @ 20-25/55°NFJ CX, NFJ GCX -15° --- 13.8 20.6 7 14 1 @ 60/50° ----- 2-3 @ 20-25/55°NFJ ECX, NFJ GECX -15° 7.8 --- --- 7 14 1 @ 60/50° ----- 2-3 @ 20-25/55°NFMJ CX, NFMJ GCX -15°/ --- 13.8 20.6 7/ 14/ 1 @ 60/50°/ ----- 2-3 @ 20-25/55°/(DUAL TEMP) + 22° 37 50 1 @ 36/50° ----- 2-3 @ 16-20/55°NFWX, NFWGX -15° --- 13.8 20.6 7 14 1 @ 46/50° ----- 2-3 @ 20-25/55°NFWEX -15° 6...

关注我们

关注微信公众号

您选择了以下内容

页面底部区域 foot.htm