General Technical Information

TubeFit Industrial Products provide a wide range of hose & fitting solutions to suit all industries.

Thread Information

What Is A Pipe Thread?

A ‘Pipe Thread’ is a ‘universal’ thread that enables port connection via a common thread form. With the addition of a tube connection fitting, pipe threads can be used to connect tube to the port of a piece of equipment or allow adaptation, both sizing and/or configuration, to satisfy a given situation. However, depending upon the place of manufacture or the industry in which you are working, different ‘universal’ pipe threads may be specified.

In Australia, most specifications will demand either BSP (British Standard Pipe – Taper or Parallel) or NPT/NPS (American Pipe (Taper/Straight). The fundamental difference with these two ‘universal’ threads is the pitch or threads per inch (T.P.I.) and the thread angle.

Pipe thread sizes are determined by the ‘nominal bore’ of pipe and, as such, can be very confusing when ordered. Confusion is often encountered because the wall thickness of the pipe is not included in the calculation for BSPT, BSPP, NPT or NPS thread specifications.

Threads At A Glance

The following tables have been prepared to show information relating to the thread form of both ends of a tube connection fitting – tube end and pipe end.

Nom. Size	British Pipe Thread BSP (G Series)
	Threads		BSP	BSP
	T.P.I.	Angle	O.D. (mm)	Min. Dia. (mm)	Max. Dia. (mm)
1/8″	28	55	9.62	9.51	9.73
1/4″	19	55	13.03	12.91	13.16
3/8″	19	55	16.54	16.41	16.66
1/2″	14	55	20.82	20.67	20.96
3/4″	14	55	26.30	26.16	26.44
1″	11	55	33.07	32.89	33.25
11/4″	11	55	41.73	41.55	41.91
11/2″	11	55	47.62	47.44	47.80
2″	11	55	59.44	59.25	59.62

Nom. Size	American Pipe Thread NPS – National Pipe Straight / NPT – National Pipe Taper
	Threads		NPS	NPT
	T.P.I.	Angle	O.D. (mm)	Min. Dia. (mm)	Max. Dia. (mm)
1/8″	27	60	10.29	10.27	10.29
1/4″	18	60	13.77	13.69	13.77
3/8″	18	60	17.15	17.07	17.15
1/2″	14	60	21.34	21.26	21.34
3/4″	14	60	26.67	26.59	26.67
1″	11.5	60	33.40	33.31	33.40
11/4″	11.5	60	42.16	42.07	42.16
11/2″	11.5	60	48.26	48.17	48.26
2″	11.5	60	60.33	60.24	60.33

AS IS0 7.1/2 (previously AS 1722.1) Sealing Threads of Whitworth Form (R Series)

Commonly termed BSPT, gas thread, sealing thread, dry seal thread or engineering thread, AS IS0 7.1/2 (previously AS 1722.1) require mating threads, including a combination of parallel and tapered sealing ends, to effect a seal without the aid of any form of thread sealant or gasket. Generally longer and more bulky than the AS1722.2 equivalents, pipe threads manufactured to meet AS IS0 7.1/2 (previously AS 1722.1) have a limited working life if continually disassembled and re-made.

AS1722.2 Fastening Threads of Whitworth Form (G Series)

Commonly termed BSP, MI, FI or plumbing thread, the thread will require a sealing aid to effect a positive seal. The sealing agent may take the form of a gasket, O-Ring, thread tape, hemp or thread paste. Threads manufactured to AS1722.2 are used extensively in the Plumbing Industry. If used in the correct manner, threads manufactured to AS1722.2 can be disassembled and re-made many times over.

Tube Thread Table

A ‘tube thread’ is a generic term used for identifying the thread form, of the tube end, of a tube connection fitting and not a specific thread.

Tube O.D.	Standard Compression	Internal Compression	SAE 45˚ Flare	SAE 45˚ Inverted Flare
1/8″	5/16″ x 24UNF	9/32″ x 26BRASS	5/16″ x 24UNF	5/16″ x 28UNS
3/16″	3/8″ x 24UNF	3/8″ x 24UNF	3/8″ x 24UNF	3/8″ x 24UNF
1/4″	7/16″ x 24UNS	7/16″ x 24UNS	7/16″ x 20UNF	7/16″ x 24UNS
5/16″	1/2″ x 24UNS	1/2″ x 24UNS	1/2″ x 20UNF	1/2″ x 20UNF
3/8″	9/16″ x 24UNEF	9/16″ x 24UNEF	5/8″ x 18UNF	5/8″ x 18UNF
1/2″	11/16″ x 20UN	3/4″ x 24UNS	3/4″ x 16UNF	3/4″ x 18UNS
5/8″	n/a	7/8″ x 20UNEF	7/8″ x 14UNF	n/a
3/4″	n/a	1.025 x 18UNS	11/16″ x 14UNF	n/a
4mm	5/16″ x 24UNF	n/a	n/a	n/a
6mm	7/16″ x 24UNS	n/a	n/a	n/a
8mm	1/2″ x 24UNS	n/a	n/a	n/a
10mm	9/16″ x 24UNEF	n/a	n/a	n/a
12mm	11/16″ x 20UN	n/a	n/a	n/a

Thread Abbreviations & Definitions

The thread types listed below are representative of some of the common threads and terms used in general industry.

Thread Abbreviation	Definition
ANP	American National Pipe
ANPT	American National Pipe Taper
Brass Thread	Fine thread common to brass machining and always 26TPI regardless of major diameter (Whitworth form)
BSP	British Standard Pipe
BSPP	British Standard Pipe Parallel
BSPT	British Standard Pipe Tapered
Dry Seal	A generic term referring to a thread that seals without the aid of a thread sealant or washer
Engineering Thread	A term referring to a thread capable of sealing without the aid of a thread sealant or washer
F.I.	Female Iron (BSP Female – common in the Plumbing Industry)
GAS	A term referring to BSPT or NPT thread (common in Automotive and Plumbing Industry)
J.I.C.	Joint Industries Conference or J.I. Case
M.I.	Male Iron (BSP Male – common in the Plumbing Industry)
NPS	National Pipe Straight (American pipe thread)
NPT	National Pipe Taper (American pipe thread)
NPTF	National Pipe Taper Fuel (Internal, straight, American pipe thread)
TPI	Threads per inch
Pipe Thread	A term referring to BSPT/BSPP or NPT/NPS thread
Plumbing Thread	A term referring to BSP fastening thread
P.T.	Sealing, tapered, pipe thread of Whitworth form
SAE	Society of Automotive Engineers
Sealing Thread	A term referring to a thread capable of sealing without the aid of a thread sealant or washer
Tube Thread	Thread used on the tube end of a tube connection fitting
UN	Unified National (not standard UNF)
UNEF	Unified National Extra Fine
UNF	Unified National Fine (formally SAE)
UNS	Unified National Special (not standard UNF)

Maximum Working Pressures

Maximum Working Pressure Tables for Tube Connection Fittings (kPa)

All working pressures are calculated at an ambient temperature using a safety factor of 4:1. Generally, working pressure is dependent upon the type of tubing used and not the fitting. Consequently the tables shown below should be used as a guide only.

Hydraulic Applications Only – Maximum Working Pressure (kPa)

Tube O.D.	Stand Compression	Internal Compression	SAE 45˚ Flare	SAE 45˚ Inverted Flare	Fleetfit Air Brake	Pneufit
1/8″	3500	3500	17250	17250	n/r	n/r
3/16″	3500	3500	17250	17250	n/r	n/r
1/4″	2750	2750	13750	13750	n/r	n/r
5/16″	2750	2750	13750	13750	n/r	n/r
3/8″	2000	2000	10400	10400	n/r	n/r
1/2″	2000	2000	7000	7000	n/r	n/r
5/8″	n/a	1400	7000	n/a	n/r	n/r
3/4″	n/a	1400	7000	n/a	n/r	n/r
4mm	3500	n/a	n/a	n/a	n/r	n/r
6mm	2750	n/a	n/a	n/a	n/r	n/r
8mm	2750	n/a	n/a	n/a	n/r	n/r
10mm	2000	n/a	n/a	n/a	n/r	n/r
12mm	2000	n/a	n/a	n/a	n/r	n/r

n/a = Not Available

n/r = Not Recommended for Hydraulic Applications

Pneumatic Applications – Maximum Working Pressure (kPa)

Tube O.D.	Stand Compression	Internal Compression	SAE 45˚ Flare	SAE 45˚ Inverted Flare	Fleetfit Air Brake	Pneufit
1/8″	2000	2000	4800	4800	1050	1800
3/16″	1750	1750	4800	4800	1050	1800
1/4″	1400	1400	4800	4800	1050	1800
5/16″	1400	1400	4800	4800	1050	1800
3/8″	1050	1050	2750	2750	1050	1800
1/2″	1050	1050	1750	1750	1050	1800
5/8″	n/a	700	1750	n/a	1050	n/a
3/4″	n/a	700	1750	n/a	1050	n/a
4mm	2000	n/a	n/a	n/a	1050	1800
6mm	1400	n/a	n/a	n/a	1050	1800
8mm	1400	n/a	n/a	n/a	1050	1800
10mm	1050	n/a	n/a	n/a	1050	1800
12mm	1050	n/a	n/a	n/a	1050	1800

n/a = Not Available

Pipe End Pressure Ratings – Maximum Working Pressure (kPa)

Pipe Size	Brass Alloy
Pipe Size	Hydraulic	Pneumatic
1/8″	13750	3500
1/4″	13750	3500
3/8″	13750	2750
1/2″	10400	2750
3/4″	7000	2000
1″	4000	1250

Copper Annealed Seamless ASTM B-75 or Equivalent

Calculated, maximum working pressure (kPa) for temperatures between 6.7° and 37.8°C. Burst pressure of copper tube is 5 times that of the working pressure.

Tube Wall Thickness – Maximum Working Pressure (kPa)

Tubing O.D.	0.71mm ISWG 22	0.91mm ISWG 20	1.22mm ISWG 18	1.63mm ISWG 16	2.03mm ISWG 14
1/8″	18700	23700	–	–	–
3/16″	11920	15300	22150	–	–
1/4″	8780	12080	16200	22000	–
5/16″	6870	9380	12600	17300	–
3/8″	5650	7680	10200	14000	18500
1/2″	4170	5630	7450	10100	13450
5/8″	–	4440	6090	7980	10400
3/4″	–	3670	4850	6540	8540
1″	–	2720	3700	5070	6260

Corrosion Rating Charts

Alloy Group Definitions

Copper
Brass
352 DZR Brass Alloy

Corrosion Rating Charts

The accompanying charts give relative corrosion resistance ratings for copper and the commonly used copper alloys. These ratings are based on consideration of laboratory test data, service experience and a general knowledge of corrosion resistant properties; however, it must be fully recognised that the ratings are relative only and definite unqualified recommendations of corrosion resistance cannot be made.

When interpreting the data, it should be remembered that corrosion resistance or rate of corrosion is greatly affected by conditions of exposure such as presence of oxidising agents, velocity of solution, aeration, temperature and similar factors.

In general, the information in the tables refers to non-oxidising conditions, low velocities (below 1.2 metres per second) and ambient temperatures.

Corrosion Rating	Definition
E (Excellent)	The metal should be suitable under most conditions of use.
G (Good)	The metal offers good corrosion resistance. It may be considered in place of a metal with an “E” rating when some property other than corrosion resistance governs its use.
F (Fair)	The metal offers fair corrosion resistance.
N (Not to be used)	The metal is not suitable.

Corrosion Media	Copper	385 Brass	352 DZR Brass
Acetic Acid	G	N	F
Acetic Anhydride	G	N	F
Acetone	E	E	E
Acetylene	N	E	N
Alcohols	E	E	E
Alum	G	N	G
Alumina	G	E	E
Aluminium Chloride	E	N	F
Aluminium Hydroxide	G	E	E
Aluminium Sulfate	E	N	G
Ammonia, Absolutely dry	N	E	E
Ammonia, moist	N	N	N
Ammonium Hydroxide	N	N	N
Ammonium Chloride	N	N	N
Ammonium Nitrate	F	N	N
Ammonium Sulfate	E	N	N
Amyl Acetate	E	G	E
Amyl Alcohol	F	E	E
Aniline	F	F	F
Aniline Dyes	E	F	F
Asphalt	E	E	E
Atmosphere, Industrial	E	G	E
Atmosphere, Marine	E	G	E
Atmosphere, Rural	E	E	E
Barium Carbonate	G	E	E
Barium Chloride	E	N	F
Barium Hydroxide	E	G	E
Barium Sulfate	F	E	E
Barium Sulfide	E	G	G
Beer	E	G	E
Beet Sugar Syrups	E	G	E
Benzine	E	E	E
Benzoic Acid	E	G	E
Benzol	E	E	E
Black Liquor	F	N	N
Bleaching Powder, Wet	G	N	G
Borax	E	E	E
Bordeaux Mixture	E	G	E
Boric Acid	E	G	E
Brines	G	N	G
Bromine, Dry	E	E	E
Bromine, Moist	G	N	F
Butane	E	E	E
Butyl Alcohol	E	E	E
Butyric Acid	G	F	G
Calcium Bisulfite	G	N	G
Calcium Chloride	G	N	G
Calcium Hydroxide	E	G	E
Calcium Hypochlorite	G	N	G
Cane Sugar Syrups	E	G	E
Carbolic Acid	G	G	G
Calcium Dioxide, Dry	E	E	E
Carbon Dioxide, Moist	G	F	G
Carbonated Water	G	F	G
Carbonated Beverages	G	F	G
Carbon Disulfide	G	E	E
Carbon Tetrachloride, Dry	E	E	E
Carbon Tetrachloride, Moist	G	N	G
Castor Oil	E	E	E
Chlorine, Dry	E	E	E
Chlorine, Moist	F	N	F
Chloracetic Acid	G	N	F
Chloroform, Dry	E	E	E
Chromic Acid	N	N	N
Cider	E	F	E
Citric Acid	E	F	E
Coffee	E	E	E
Copper Chloride	F	N	F
Copper Nitrate	F	N	F
Copper Sulfate	G	N	G
Corn Oil	E	G	E
Cottonseed Oil	E	G	E
Creosote	E	G	E
Crude Oil	G	F	G
Ethers	E	E	E
Ethyl Acetate	E	G	E
Ethyl Alcohol	E	E	E
Ethyl Chloride	G	F	G
Ethylene Glycol	E	G	E
Ferric Chloride	N	N	N
Ferric Sulfate	N	N	N
Ferrous Chloride	G	N	G
Ferrous Sulfate	G	N	G
Formaldehyde	E	G	E
Formic Acid	G	N	F
Freon	E	E	E
Fruit Juices	G	N	F
Fuel Oil	E	F	E
Furfural	E	G	E
Gasoline	E	E	E
Gelatine	E	E	E
Glucose	E	E	E

Corrosion Media	Copper	385 Brass	352 DZR Brass
Glue	E	G	E
Glycerine	E	E	E
Hydrobromic Acid	F	N	F
Hydrocarbons, Pure	E	E	E
Hydrochloric Acid	F	N	F
Hydrocyanic Acid	N	N	N
Hydrofluoric Acid	F	N	N
Hydrofluosilicic Acid	G	N	G
Hydrogen	E	E	E
Hydrogen Peroxide	G	F	G
Hydrogen Sulfide, Dry	E	E	E
Hydrogen Sulfide, Moist	N	F	G
Kerosene	E	E	E
Lacquers	E	E	E
Lacquer Solvents	E	E	E
Lactic Acid	G	N	F
Lime	E	E	E
Lime-Sulfur	F	G	G
Linseed Oil	G	G	G
Magnesium Chloride	G	N	F
Magnesium Hydroxide	E	E	E
Magnesium Sulfate	E	F	E
Mercury	N	N	N
Mercury Salts	N	N	N
Methyl Alcohol	E	E	E
Methyl Chloride, Dry	E	E	E
Milk	E	G	E
Mine Water	F	N	F
Natural Gas	G	E	E
Nitric Acid	N	N	N
Nitrogen	E	E	E
Oleic Acid	G	F	G
Oxalic Acid	G	N	F
Oxygen	E	E	E
Palmitic Acid	G	F	G
Paraffin	E	E	E
Phosphoric Acid	G	N	F
Potassium Carbonate	E	G	E
Potassium Chloride	G	N	G
Potassium Chromate	E	E	E
Potassium Cyanide	N	N	N
Potassium Dichromate Acid	N	N	N
Potassium Hydroxide	G	F	G
Potassium Sulfate	E	G	E
Propane	E	E	E
Rosin	E	E	E
Sea Water	G	F	E
Sewage	E	F	E
Silver Salts	N	N	N
Soap Solutions	E	G	E
Sodium Bicarbonate	G	F	G
Sodium Bisulfate	G	N	G
Sodium Carbonate	E	G	E
Sodium Chloride	G	N	G
Sodium Chromate	E	E	E
Sodium Cyanide	N	N	N
Sodium Dichromate, Acid	N	N	N
Sodium Hydroxide	G	F	G
Sodium Hypochlorite	F	N	F
Sodium Nitrate	G	F	G
Sodium Peroxide	F	N	F
Sodium Phosphate	E	G	E
Sodium Sillicate	E	G	E
Sodium Sulfate	E	G	E
Sodium Sulfide	F	G	G
Sodium Sulfite	G	N	G
Sodium Thiosulfate	F	G	G
Steam	E	F	E
Stearic Acid	G	F	G
Sugar Solutions	E	G	E
Sulfur, Dry	G	E	E
Sulfur, Molten	N	N	N
Sulfur Chloride, Dry	E	E	E
Sulfur Dioxide, Dry	E	E	E
Sulfur Dioxide, Moist	G	N	G
Sulfur Trioxide, Dry	E	E	E
Sulfuric Acid	G	N	F
Sulfurous Acid	G	N	G
Tannic Acid	E	G	E
Tar	E	G	E
Tartaric Acid	E	F	E
Toluene	E	E	E
Trichloracetic Acid	G	N	F
Trichlorethylene, Dry	E	E	E
Trichlorethylene, Moist	G	F	G
Turpentine	E	G	E
Varnish	E	E	E
Vinegar	G	N	F
Water, Potable	E	N	E
Zinc Chloride	F	N	F
Zinc Sulfate	G	N	G

Conversion Tables

Standard Conversions

Pressure (psi to kPa)

psi	kPa	kPa	psi
1	6.9	1	0.15
2	13.8	2	0.29
3	20.7	3	0.44
4	27.6	4	0.58
5	34.5	5	0.73
6	41.4	6	0.87
7	48.3	7	1.02
8	55.2	8	1.16
9	62.1	9	1.31
10	69.0	10	1.45
50	345	50	7
100	690	100	15
250	1724	250	36
500	3448	500	73
1000	6895	1000	145
5000	34475	5000	725
10000	68950	10000	1450
20000	137900	20000	2901
50000	344750	50000	7252
75000	517125	75000	10877
100000	689500	100000	14503

Length / Distance

Metric	Imperial	Imperial	Metric
1mm	0.0393 inch	1/8 inch	3.17mm
1cm	0.3937 inch	1 inch	25.40mm
10cm	0.3281 foot	1 foot	30.48cm
1m	1.0936 yard	1 yard	0.914m
1km	0.6214 mile	1 mile	1.61km

Temperature

Fahrenheit	Celsius
0	-17.8
5	-15.0
10	-12.2
32	0.0
50	10.0
75	23.9
100	37.8
150	65.6
200	93.3
212	100.0

Pressure Conversion

	lbs/in²	kg/cm²	kPa	Bar
lbs/in²	1	0.07031	6.895	0.0689
kg/cm²	14.22	1	98.05	0.981
kPa	0.1451	0.0102	1	0.01
Bar	14.51	1.02	100	1

Imperial to Metric

Inches	Inches	mm	Inches	Inches	mm
Fraction	Decimal	mm	Fraction	Decimal	mm
1/64	0.016	0.397	33/64	0.516	13.097
1/32	0.031	0.794	17/32	0.531	13.494
3/64	0.047	1.191	35/64	0.547	13.891
1/16	0.063	1.588	9/16	0.563	14.288
5/64	0.078	1.984	37/64	0.578	14.684
3/32	0.094	2.381	19/32	0.594	15.081
7/64	0.109	2.778	39/64	0.609	15.478
1/8	0.125	3.175	5/8	0.625	15.875
9/64	0.141	3.572	41/64	0.641	16.272
5/32	0.156	3.969	21/32	0.656	16.669
11/64	0.172	4.366	43/64	0.672	17.066
3/16	0.188	4.763	11/16	0.688	17.463
13/64	0.203	5.159	45/64	0.703	17.859
7/32	0.219	5.556	23/32	0.719	18.256
15/64	0.234	5.953	47/64	0.734	18.653
1/4	0.250	6.350	3/4	0.750	19.050
17/64	0.266	6.747	49/64	0.766	19.447
9/32	0.281	7.144	25/32	0.781	19.844
19/64	0.297	7.541	51/64	0.797	20.241
5/16	0.313	7.938	13/16	0.813	20.638
21/64	0.328	8.334	53/64	0.828	21.034
11/32	0.344	8.731	27/32	0.844	21.431
23/64	0.359	9.128	55/64	0.859	21.828
3/8	0.375	9.525	7/8	0.875	22.225
25/64	0.391	9.922	57/64	0.891	22.622
13/32	0.406	10.319	29/32	0.906	23.019
27/64	0.422	10.716	59/64	0.922	23.416
7/16	0.438	11.113	15/16	0.938	23.813
29/64	0.453	11.509	61/64	0.953	24.209
15/32	0.469	11.906	31/32	0.969	24.606
31/64	0.484	12.303	63/64	0.984	25.003
1/2	0.500	12.700	1	1.000	25.400

Conversion Factors

Mass

From	To	Multiply by
ounce (oz)	gram (g)	28.349
gram (g)	ounce (oz)	0.035
pound (lb)	kilogram (kg)	0.454
kilogram (kg)	pound (lb)	2.205
ton	tonne	1.016
tonne	ton	0.984

Density

From	To	Multiply by
pound / cubic inch (lb/in³)	gram / cubic centimetre (g/cm³)	27.679
gram / cubic centimetre (g/cm³)	pound / cubic inch (lb/in³)	0.036
pound / cubic foot (lb/ft³)	kilogram / cubic metre (kg/m³)	16.018
kilogram / cubic metre (kg/m³)	pound / cubic foot (lb/ft³)	0.062
pound / cubic yard (lb/yd³)	kilogram / cubic metre (kg/m³)	0.593
kilogram / cubic metre (kg/m³)	pound / cubic yard (lb/yd³)	1.684

Pressure

From	To	Multiply by
pound / foot (lb/ft)	kilogram / metre (kg/m)	1.4882
kilogram / metre (kg/m)	pound / foot (lb/ft)	0.672
pound / square inch (lb/in²)	kilogram / square centimetre (kg/cm²)	0.07031
kilogram / square centimetre (kg/cm²)	pound / square inch (lb/in²)	14.22
pound / square inch (lb/in²)	kilopascal (kPa)	6.895
kilopascal (kPa)	pound / square inch (lb/in²)	0.145
pound / square inch (lb/in²)	megapascal (MPa)	0.006895
megapascal (MPa)	pound / square inch (lb/in²)	145.04
ton / square inch (ton/in²)	megapascal (MPa)	15.444
megapascal (MPa)	ton / square inch (ton/in²)	0.0647
bar	kilogram / square centimetre (kg/cm²)	1.02
kilogram / square centimetre (kg/cm²)	bar	0.981
bar	pound / square inch (lb/in²)	14.51
pound / square inch (lb/in²)	bar	0.0689
bar	kilopascal (kPa)	100
kilopascal (kPa)	bar	0.01

Temperature

From	To	Use Equation
centigrade (C)	fahrenheit (F)	(C. x 1.8) + 32
fahrenheit (F)	centigrade (C)	(F – 32) / 1.8

Length

From	To	Multiply by
thou. inch (µin)	millimetre (mm)	0.0254
millimetre (mm)	thou. inch (µin)	0.0393
inch (in)	centimetre (cm)	2.54
centimetre (cm)	inch (in)	0.3937
foot (ft)	metre (m)	0.3048
metre (m)	foot (ft)	3.2808
mile	kilometre (km)	0.6213
kilometre (km)	mile	1.6093

Volume

From	To	Multiply by
cubic inches (ci)	cubic centimetres (cc)	16.3871
cubic centimetres (cc)	cubic inches (ci)	0.061
cubic foot / min (cfm)	litre / min (l/min)	28.3168
litre / min (l/min)	cubic foot / min (cfm)	0.0353
cubic yard (yd³)	cubic metre (m³)	0.7645
cubic metre (m³)	cubic yard (yd³)	1.3079
fluid ounce (fl oz)	ml (cm³)	28.4131
ml (cm³)	fluid ounce (fl oz)	0.035
pint	litre (dm3)	0.5682
litre (dm3)	pint	1.7605
imperial gallon	litre (dm3)	4.5506
litre (dm3)	imperial gallon	0.2197