SS U Tube, Shell and Tube Heat Exchanger manufacturer in India

Stainless Steel Heat Exchanger Tube

Stainless Steel Heat Exchanger Tube

What is Stainless Steel Heat Exchanger Tube?

The Stainless Steel Heat Exchanger Tube is specially designed for use in applications that involve the use of high temperature and pressure. These stainless tubes are resistant to corrosion and rust due to the presence of around 10.5% more chromium than other alloys. Thus, they are widely used in boilers, furnaces, and heaters. The stainless steel heat exchanger tubes are also known for their high quality in terms of thermal conductivity.
One of the best qualities of these heat exchanger tubes is that they can be used with various process industries. They are very effective in reducing leakage in your pressure vessel and instrumentation system.

How do you calculate the number of heat exchanger tubes?

The total number of tubes required in exchangers and shells (NT) can easily be calculated with the given equation. Remember that the calculations are based on the overall heat transfer area requirement.
calc
Wherein Aoverall comes from the heat transfer rate equation and it is the overall heat transfer surface area, OD denotes the outer diameter of the selected size of the tube and L is the length of the total tube. The equation is quite simple and based on the geometry of the given shells and tube heat exchanger. It is easily understood from this equation that the higher the outer diameter of the tube, or greater its length, the lesser tube you would need for a given application.

Why use Stainless Steel U-Bent Tubes?

The Stainless Steel U-Bent Tubes are primarily used in the heat exchanger systems. It is widely used in industries like petrochemical machine building and nuclear power. The U-bend tubes can be manufactured from both welded and seamless variants. Also, these can be customized to meet the requirements of individual industries. They can be cut according to the leg length requested by the clients. The inside of the tubes are thoroughly cleaned with the help of compressed air. The SS u-bend pipes are mostly available in all steel grades which are the same as that of the heat exchanger tubes. These pipes are mostly supplied in annealed and pickled conditions. However, clients can also get them in stabilization and stress relieving conditions.

Difference between a straight tube and a U-tube

Choosing the right design of the tube is critical for proper application, or else it can lead to exchanger damage or fouling. Both the tubes are quite identical, except the fact that they differ in their designs and rear bonnet.
The straight tubes are quite simple to use and they are quite versatile too. These tubes are quite easy to clean, as they do not have any complex bends to work on.

Stainless Steel U-tubes can be helpful in some cases, where straight tubes might fall short. Unlike the straight tubes, these tubes do not have the risk of getting damaged due to thermal expansion. These can also be removed easily from the exchanger.

Heat treatment of ASTM A213/ SA 213 Stainless Steel U Tube

The ASTM A213/ SA 213 Stainless Steel U Tube is made of the ASTM A213 material that comes with a hardness of 275 HV. The specification is when the tube is in hardened condition, which means it has been austenitized and cooled till the room temperature. The material includes titanium in its composition, which reduces the weight of the SA 213 Stainless Steel U Tube. Also, these tubes are capable of lasting long in high temperatures, and thus they are widely used in heat exchangers and superheaters. The application of ASTM A213 Stainless Steel U Tube is found in boilers and condensers. These high-quality tubing solutions are available in different sizes and types. They are easy to install and maintain.

Advantages of SS Heat Exchanger Tube

There are various reasons behind the popularity of Stainless Steel Heat Exchanger Tube. These have a robust design, and thus are capable of withstanding extreme conditions, including high temperature and pressure. The stainless steel material makes these tubes resistant to corrosion and increases their durability. The SS Heat Exchanger Tube is known for its long service life. The stainless steel material is also capable of withstanding limestone deposition and helps to reduce the deposits of other materials.

300 Series Stainless Steel Heat Exchanger Tubes are also popular due to their strength. They can withstand mechanical influences like high vibrations, steam hammers, etc. The stainless steel also promotes easy maintenance of the tubes.

Looking for Heat Exchanger Tube manufacturers in India? We produce SS Tube Coil Heat Exchanger and U Bend Pipe in India and follow Eddyfi Technologies to know the Stainless Steel U Tube defects

Spec Chart of Stainless Steel Heat Exchanger Tube

Dimensions ASTM, ASME and API
Welded Pipes 5.0 mm – 1219.2 mm
EFW Pipes 5.0 mm – 1219.2 mm
Testing Provided By Supplier H2 SERVICE, NACE TM0177, NACE TM0284, SSC TEST, NACE MR0175, HIC TEST, IBR, etc.
Specialized in Large Diameter Size
Seamless Pipes Manufacturer 4 to 219mm W. T.: 0.5 to 20mm
Size 15″NB TO 150″NB IN
Schedule SCH5, SCH10, SCH40, STD, SCH80, SCH160
Available Type By Manufacturer Seamless / ERW / Welded / Fabricated / LSAW
Form Round, Hydraulic Etc
End Plain End, Beveled End, Treaded
Length Single Random, Double Random & Cut Length.

ASTM A249 Heat Exchanger Tube Dimensions

DN NPS(Inch) D(mm) SCH5S SCH10S SCH40S STD SCH40 SCH80 XS SCH80S SCH160 XXS
6 1/8 10.30 - 1.24 1.73 1.73 1.73 2.41 2.41 2.41 - -
8 1/4 13.70 - 1.65 2.24 2.24 2.24 3.02 3.02 3.02 - -
10 3/8 17.10 - 1.65 2.31 2.31 2.31 3.20 3.20 3.20 - -
15 1/2 21.30 1.65 2.11 2.77 2.77 2.77 3.73 3.73 3.73 4.78 7.47
20 3/4 26.70 1.65 2.11 2.87 2.87 2.87 3.91 3.91 3.91 5.56 7.82
25 1 33.40 1.65 2.77 3.38 3.38 3.38 4.55 4.55 4.55 6.35 9.09
32 1 1/4 42.20 1.65 2.77 3.56 3.56 3.56 4.85 4.85 4.85 6.35 9.70
40 1 1/2 48.30 1.65 2.77 3.68 3.68 3.68 5.08 5.08 5.08 7.14 10.15
50 2 60.30 1.65 2.77 3.91 3.91 3.91 5.54 5.54 5.54 8.74 11.07

Welded Stainless Steel Tube For Heat Exchanger Standards

ASTMASME
A-789SA-789
B-163SB-163
A-249, A-269SA-249

Standards of Seamless SS Tubes For Heat Exchanger

ASTMASMEEN
A-789SA-78910216-5
B-163 B-407 SB-163 SB-407 10216-5
B-668SB-66810216-5
A-269SB-67710216-5
A-213 A-269SA-21310216-5

Stainless Steel Heat Exchanger Tube Price List

Products Price
seamless stainless steel heat exchanger tube $550 Per Ton
6MM Precision Stainless Steel Micro tubes Heat Exchanger $27 Per Pieces
304 Stainless Steel Shell and tubes Heat Exchanger $300 Per Piece
100kw stainless steel finned tubes heat exchanger for trailers $588 Per Piece
heat exchanger stainless steel tubes $1.50 Per Kg

Parameters of Stainless Steel U Tube

Main performance parameters Structure   shell and tube type
Area of Heat Transfer   125 square meter
Pitch mm 456
Technical Parameters Design Pressure MPa shell:0.6  tubes :1.6
Design temperature °C shell:250  tubes :210
Working temperature °C shell:230/210 tube:170/190
Dimension Dia. mm Φ662
Length mm 7040
Weight kg 2165

Stainless Steel U Bend Chemical Properties

Grade C Mn Si P S Cr Mo Ni N Ti Fe
304 min. 18.0 8.0
max. 0.08 2.0 0.75 0.045 0.030 20.0 10.5 0.10
304L min. 18.0 8.0
max. 0.030 2.0 0.75 0.045 0.030 20.0 12.0 0.10
304H min. 0.04 18.0 8.0
max. 0.010 2.0 0.75 0.045 0.030 20.0 10.5
SS 310 0.015 2 0.015 0.020 0.015 24.00 26.00 0.10 19.00 21.00 54.7 min
SS 310S 0.08 2 1.00 0.045 0.030 24.00 26.00 0.75 19.00 21.00 53.095 min
SS 310H 0.04 0.10 2 1.00 0.045 0.030 24.00 26.00 19.00 21.00 53.885 min
316 min. 16.0 2.03.0 10.0  
max. 0.035 2.0 0.75 0.045 0.030 18.0 14.0  
316L min. 16.0 2.03.0 10.0    
max. 0.035 2.0 0.75 0.045 0.030 18.0 14.0  
316TI 0.08 10.00 14.00 2.0 0.045 0.030 16.00 18.00 0.75 2.00 3.00
317 0.08 2 1 0.045 0.030 18.00 20.00 3.00 4.00 57.845 min
SS 317L 0.035 2.0 1.0 0.045 0.030 18.00 20.00 3.00 4.00 11.00 15.00 57.89 min
SS 321 0.08 2.0 1.0 0.045 0.030 17.00 19.00 9.00 12.00 0.10 5(C+N) 0.70
SS 321H 0.04 0.10 2.0 1.0 0.045 0.030 17.00 19.00 9.00 12.00 0.10 4(C+N) 0.70
347/ 347H 0.08 2.0 1.0 0.045 0.030 17.00 20.00 9.0013.00
410 min. 11.5
max. 0.15 1.0 1.00 0.040 0.030 13.5 0.75
446 min. 23.0 0.10
max. 0.2 1.5 0.75 0.040 0.030 30.0 0.50 0.25
904L min. 19.0 4.00 23.00 0.10
max. 0.20 2.00 1.00 0.045 0.035 23.0 5.00 28.00 0.25

Exporter and supplier of Stainless Steel U Tube Bundle and Shell Tube Heat Exchanger in Asia, check size chart, surface area

Mechanical Properties of U Shaped Stainless Steel Tube

Grade Density Melting Point Tensile Strength Yield Strength (0.2%Offset) Elongation
304/ 304L 8.0 g/cm3 1400 °C (2550 °F) Psi 75000 , MPa 515 Psi 30000 , MPa 205 35 %
304H 8.0 g/cm3 1400 °C (2550 °F) Psi 75000 , MPa 515 Psi 30000 , MPa 205 40 %
310 / 310S / 310H 7.9 g/cm3 1402 °C (2555 °F) Psi 75000 , MPa 515 Psi 30000 , MPa 205 40 %
306/ 316H 8.0 g/cm3 1400 °C (2550 °F) Psi 75000 , MPa 515 Psi 30000 , MPa 205 35 %
316L 8.0 g/cm3 1399 °C (2550 °F) Psi 75000 , MPa 515 Psi 30000 , MPa 205 35 %
317 7.9 g/cm3 1400 °C (2550 °F) Psi 75000 , MPa 515 Psi 30000 , MPa 205 35 %
321 8.0 g/cm3 1457 °C (2650 °F) Psi 75000 , MPa 515 Psi 30000 , MPa 205 35 %
347 8.0 g/cm3 1454 °C (2650 °F) Psi 75000 , MPa 515 Psi 30000 , MPa 205 35 %
904L 7.95 g/cm3 1350 °C (2460 °F) Psi 71000 , MPa 490 Psi 32000 , MPa 220 35 %

Stainless Steel Heat Exchanger Tube grade correlation and equivalents

STANDARD WERKSTOFF NR. UNS JIS BS GOST AFNOR EN
SS 304 1.4301 S30400 SUS 304 304S31 08Х18Н10 Z7CN18‐09 X5CrNi18-10
SS 304L 1.4306 / 1.4307 S30403 SUS 304L 3304S11 03Х18Н11 Z3CN18‐10 X2CrNi18-9 / X2CrNi19-11
SS 304H 1.4301 S30409
SS 310 1.4841 S31000 SUS 310 310S24 20Ch25N20S2 X15CrNi25-20
SS 310S 1.4845 S31008 SUS 310S 310S16 20Ch23N18 X8CrNi25-21
SS 310H S31009
SS 316 1.4401 / 1.4436 S31600 SUS 316 316S31 / 316S33 Z7CND17‐11‐02 X5CrNiMo17-12-2 / X3CrNiMo17-13-3
SS 316L 1.4404 / 1.4435 S31603 SUS 316L 316S11 / 316S13 03Ch17N14M3 / 03Ch17N14M2 Z3CND17‐11‐02 / Z3CND18‐14‐03 X2CrNiMo17-12-2 / X2CrNiMo18-14-3
SS 316H 1.4401 S31609
SS 316Ti 1.4571 S31635 SUS 316Ti 320S31 08Ch17N13M2T Z6CNDT17‐123 X6CrNiMoTi17-12-2
SS 317 1.4449 S31700 SUS 317
SS 317L 1.4438 S31703 SUS 317L X2CrNiMo18-15-4
SS 321 1.4541 S32100 SUS 321 X6CrNiTi18-10
SS 321H 1.4878 S32109 SUS 321H X12CrNiTi18-9
SS 347 1.4550 S34700 SUS 347 08Ch18N12B X6CrNiNb18-10
SS 347H 1.4961 S34709 SUS 347H X6CrNiNb18-12
SS 904L 1.4539 N08904 SUS 904L 904S13 STS 317J5L Z2 NCDU 25-20 X1NiCrMoCu25-20-5

Heat Exchanger Tube Size Range

Size OD Nominal Wall Outside Diameter Length Wall
1/2" (12.7) 0.065" (1.65)/0.049" (1.25) +/-0.005 (0.13) +1/8" (3.18) - 0 +/-10.0%
3/4" (19.1) 0.065" (1.65)/0.049" (1.25) +/-0.005 (0.13) +1/8" (3.18) - 0 +/-10.0%
1" (25.4) 0.065" (1.65)/0.049" (1.25) +/-0.005 (0.13) +1/8" (3.18) - 0 +/-10.0%
1-1/2" (38.1) 0.065" (1.65)/0.049" (1.25) +/-0.008" (0.20) +1/8" (3.18) - 0 +/-10.0%
2" (50.8) 0.065" (1.65)/0.049" (1.25) +/-0.008" (0.20) +1/8" (3.18) - 0 +/-10.0%
2-1/2" (63.5) 0.065" (1.65) +/-0.010" (0.25) +1/8" (3.18) - 0 +/-10.0%
3" (76.2) 0.065" (1.65) +/-0.010" (0.25) +1/8" (3.18) - 0 +/-10.0%
4" (101.6) 0.083" (2.11) +/-0.015" (0.38) +1/8" (3.18) - 0 +/-10.0%
6" (152.4) 0.083" (2.11) +/-0.030" (0.76) +1" (25.4) - 0 +/-10.0%
6" (152.4) 0.109" (2.77) +/-0.030" (0.76) +1" (25.4) - 0 +/-10.0%
8" (203.2) 0.109" (2.77) +0.061" (1.55)/-0.031" (0.79) +1" (25.4) - 0 +/-10.0%

Dimensional Tolerances of Stainless Steel Tube U Bend

Standard SIZES OD INCHES Tolerances Chart
O.D. Wall Thickness
PLUS (+) MINUS (-) PLUS (+) MINUS (-)
ASTM-A-213 Under 1.000 .004" .004" 20% 0%
ASME-SA-213 1.000 to 1.500 .006" .005" 20% 0%
Cold Finished Seamless 1.501 to 1.999 .008" .008" 22% 0%
Heat Exchanger Tube 2.000 to 2.499 .010" .010" 22% 0%
Minimum Wall 2.500 to 2.999 .012" .012" 22% 0%
  3.000 to 4.000 .015" .015" 22% 0%
  4.001 to 5.000 .015" .025" 22% 0%

Most Selling Types of Stainless Steel Heat Exchanger Tube

Stainless Steel U Tube

Stainless Steel U Tube

Stainless Steel Tube Coil Heat Exchanger

Stainless Steel Tube Coil Heat Exchanger

Corrugated Stainless Steel Tubing Heat Exchanger

Corrugated Stainless Steel Tubing Heat Exchanger

Stainless Steel Shell and Tube Heat Exchanger

Stainless Steel Shell and Tube Heat Exchanger

Stainless Steel U Bend Pipe

Stainless Steel U Bend Pipe

Stainless Steel U Bend

Stainless Steel U Bend

Stainless Steel Tube U Bend

Stainless Steel Tube U Bend

U Shaped Stainless Steel Tube

U Shaped Stainless Steel Tube

Stainless Steel Fin Tube Heat Exchanger

Stainless Steel Fin Tube Heat Exchanger

Stainless Steel Heat Exchanger Tubing

Stainless Steel Heat Exchanger Tubing

U Tube Heat Exchanger

U Tube Heat Exchanger

Heat Exchanger Tubes

Heat Exchanger Tubes

U Bend Heat Exchanger Tube

U Bend Heat Exchanger Tube

tube in tube heat exchanger

tube in tube heat exchanger

tube and tube heat exchanger

tube and tube heat exchanger

U-bent low stress tubing

U-bent low stress tubing

Seamless U Tube

Seamless U Tube

U Bundle Heat Exchanger

U Bundle Heat Exchanger

U Tube Type Heat Exchanger

U Tube Type Heat Exchanger

U Tube Exchanger

U Tube Exchanger

Shell Tube Heat Exchanger

Shell Tube Heat Exchanger

U Tube Bundle Heat Exchanger

U Tube Bundle Heat Exchanger

Cold-Drawn Seamless U Tube

Cold-Drawn Seamless U Tube

U Tube

U Tube

Heat Exchanger Tube

Heat Exchanger Tube

U Tube Bundle

U Tube Bundle

Shell and Tube Heat Exchanger

Shell and Tube Heat Exchanger

Testing And Inspection Of SS Heat Exchanger Tubes

Technology Applicable tube size Features
Eddy current testing

Approx. internal diameter: 7 mm–105 mm (0.28 in.–4.1 in.)

Approx. thickness: 0.56–3.4 mm (0.02 in.–0.13 in.)

Estimate the location of corrosion in a tube

Fast

The tube’s U-shaped section can be inspected

Works on nonferromagnetic materials.

Internal rotary inspection system (IRIS)

Approx. internal diameter: 11.4 mm–76.2 mm (0.45 in.–3 in.)

Approx. thickness: 1.7–6.1 mm (0.07 in.–0.24 in.)

Precise inspection of a whole tube

Inspectors can identify the locations, shapes, and depths of defects

Special preparation and cleanup using water are required

Remote visual inspection

Approx. internal diameter: 6 mm (0.24 in.)

Approx. thickness: None

Corrosion condition inside a tube can be visually observed

The outside of a tube cannot be inspected

The tube’s U-shaped section can be inspected

Defects can be measured

Easy to use with no special techniques required

Advantages of Stainless Steel hairpin heat exchanger tubes

  • Thermal shock.
  • All-welded baffle cages for durability.
  • Cycling.
  • Long radius U-bends for effective thermal expansion.
  • Ease of cleaning.
  • High pressure closures for pressures up to 10,000 psi.
  • High temperature differences.
  • No internal bolting.
Distributor of Stainless Steel U Tube Heat Exchanger ( Seamless/ welded) with hydro-static testing, check our online price list

Limitations and Features of SS Shell and Tube Heat Exchangers

  • Only chemical tube side cleaning is possible.
  • Access to the tubes other that the outside row is limited.
  • High pressure application is limited.
  • High degree of protection against contamination of streams.
  • Double tubesheet is possible.
  • Mechanical tube side cleaning is possible.

SS Heat Exchanger Tube Pressure Rating

SIZESINGLE BRAIDDOUBLE BRAID
Nominal SizeStatic Dynamic bend radiusMax. workingTest pressureBurst Static Dynamic bend radiusMax. workingTest pressureBurst 
bend radiuspressurepressurebend radiuspressurepressure
Inchmmmmmmbarbarbarmmmmbarbarbar
1/462510015423061625100246369984
3/8104015010515742040150168252672
1/212502008813235250200140210560
5/816502007310929250200116174464
3/42070200649625670200102153408
1259020050752009020080120320
32110250426316811025067100268
1 ½4013025032481281302505176204
25017535031461241753504973196
2 ½6520041026391042004104161164
3802054501827722054502842112
41002305601624642305602639104
51252806601624642806602537100
6150320815121848320815203080
820043510151016404351015162464
1025056012206.51026560122010.51642

U bend dimension capablity

Tube OD Tube thickness Bending Radius U tube straight “leg” length Straight tube before U bending
Min. 12,7mm / Max. 31,75mm Min. 0,70mm / Max. 4,19mm Min. 1,5 x OD / Max. 1250mm Max. 12500mm Max. 27000mm

Wall Thickness Of Stainless Steel Heat Exchanger Tube

OUTER DIAMETER (OD)0.500 - 3.000 inch
12.7 - 76.2 mm
WALL THICKNESS (WT)0.035 - 0.220 inch
0.89 - 5.52 mm

Stainless Steel Fin Tube Heat Exchanger Dimensions

Type Description Base tube
O.D. (mm)
Fin specification (mm)
Fin pitch Fin height Fin thick
Embedded G-type fin tubes 16-63 2.1-5 <17 ~0.4
Extruded Single metal combined metal 8-51 1.6-10 <17 0.2-0.4
Low fin tube t-type fin tubes 10-38 0.6-2 <1.6 ~0.3
Bamboo tube corrugated tubes 16-51 8-30 <2.5 /
Wound l/kl/ll type fin tubes 16-63 2.1-5 <17 ~0.4
String String fin tubes 25-38 2.1-3.5 <20 0.2-0.5
U-type U-type tubes 16-38 / / /
Welding HF-welding fin tubes 16-219 3-25 5-30 0.8-3
H/HH type fin tubes 25-63 8-30 <200 1.5-3.5
Studed fin tubes 25-219 8-30 5-35 φ5-20

Shell Tube Heat Exchanger Advantages

  • wide variety of engineering designs
  • wide variety of materials for optimal thermal conductivity
  • cost-effective calculations for optimal capacity
  • space saving designs
Manufacturing Stainless Steel U Bend Heat Exchanger Tube, Cooling Coils and Hairpin Tubes without any circumferential welds

Stainless Steel U Tubes

  • ЕМА RCB 2.31 − Standards of the Tubular Exchanger Manufacturers Association (9th edition).
  • АSТМ А688 − Standard Specification for Seamless and Welded Austenitic Stainless Steel Feedwater Heater Tubes.
  • АSТМ B163 − Standard technical requirements for tubes of nickel and nickel alloy for condensers and heat exchangers.
  • DIN 28179 − Steel U-tubes for tubular heat exchangers - Technical delivery conditions.

Testing Methods for SS Heat Exchanger Tubes

Flattening test

Flattening test

Drift Expanding test

Drift Expanding test

Reverse Flattening test

Reverse Flattening test

Flange test

Flange test

Flaring Test

Flaring Test

Reverse Weld Bend test

Reverse Weld Bend test

Hardness test

Hardness test

Microhardness test

Microhardness test

Tensile Test

Tensile Test

Hot Tension Test

Hot Tension Test

Burst test

Burst test

Dimensional Control Test

Dimensional Control Test

Eddy Current Testing

Eddy Current Testing

Ultrasonic Test (UT)

Ultrasonic Test (UT)

Air Under Water Test (AUW)

Air Under Water Test (AUW)

Differential Air Pressure Test

Differential Air Pressure Test

Austenite/ferrite balance

Austenite/ferrite balance

Roughness measurement

Roughness measurement

Grain Size Determination

Grain Size Determination

Positive Material Identification (PMI)

Positive Material Identification (PMI)

Macrographic analysis

Macrographic analysis

Micrographic analysis

Micrographic analysis

SEM Analysis and EDS analysis

SEM Analysis and EDS analysis

Ultrasonic wall thickness measurement

Ultrasonic wall thickness measurement

Standard Sizes of ASTM A213/ SA 213 Heat Exchager Tubing

SA 789 Stainless Steel Heat Exchager Tubes

Standard Sizes of ASTM A789/ SA 789 Stainless Steel Heat Exchager Tubes

SA 213 Stainless Steel Heat Exchager Tubes

Sizes of SS U Tube

BWG BWG BWG BWG BWG BWG BWG BWG
25 22 20 18 16 14 12 10
WT mm WT mm WT mm WT
mm
WT mm WT mm WT mm WT
mm
Outside Diameter Outside Diameter 0.508 0.71 0.89 1.24 1.65 2.11 2.77 3.40
mm inch kg/m kg/m kg/m kg/m kg/m kg/m kg/m
6.35 1/4 0.081 0.109 0.133 0.174 0.212
9.53  3/8 0.126 0.157 0.193 0.257 0.356 0.429
12.7  1/2 0.214 0.263 0.356 0.457 0.612 0.754
15.88  5/8 0.271 0.334 0.455 0.588 0.796 0.995
19.05  3/4 0.327 0.405 0.553 0.729 0.895 1.236
25.4 1    0.44 0.546 0.75 0.981 1.234 1.574 2.05
31.75 1 1/4 0.554 0.688 0.947 1.244 1.574 2.014 2.641
38.1 1 1/2 0.667 0.832 1.144 1.514 1.904 2.454 3.233
44.5 1 3/4 1.342 1.774 2.244 2.894 3.5
50.8 2    1.549 2.034 2.574 3.334 4.03
63.5 2 1/2 1.949 2.554 3.244 4.214 5.13
76.2 3    2.345 3.084 3.914 5.094 6.19
88.9 3 1/2 2.729 3.609 4.584 5.974 7.27
101.6 4    4.134 5.254 6.854 8.35
114.3 4 1/2 4.654 5.924 7.734 9.43