TRAINING DIVISION. Hose and Fittings fa t= '=BE%

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1 TRANNG DVSON '=BE% Z!Jd7L Hose and Fittings fa t= 1. PRESSURE DROP A. The most important consideration one must give to the proper selection of hoses and fittings is the pressure drop. The realization of what pressure drop is and how it effects the equipments operation must be understood. n order to understand pressure drop one must have a basic knowledge of what C.F.M. (cubic feet per minute) and p.s.i. (pounds per square inch) are. C.F.M. is defined as a given volume air that flows past a given point in one minutes time, and p.s.i. is the amount of force pushing the cubic foot of air through the hose or tool. 6. Restriction through associated items such as, hose connections, adapters, nipples, valves, filters and air and fluid controls that are being used in the system. B. The condition which effects the pressure loss in the selection of the hose are: 1. The inside diameter or crosssectional area of the hose has the greatest effect. (e.g. when a 1/2 inch.d. hose is used instead of a 1/4 inch.d. hose, the pressure loss in the half inch hose will be almost 20 times less than the 1/4 inch hose for the same conditions). BASE50 PSlG NPUT 50' LENGTHS WTH FTTNGS The amount of air that a tool consumes will remain constant for a given set of conditions. The pressure will always drop whenever the tool is turned on and, when the air begins to flow through the hose. The pressure drop will vary in relation to the adjustment made on the tool. The same pressure loss occurs when we speak of moving a fluid through a hose. Therefore one must also consider pressure loss for the proper selection of fluid hoses and fittings. Pressure drop cannot be eliminated because it will always be present. The only thing one can do is recognize the causes then minimize the effects by considering the following: 1. Frictional resistance between the fluid and the walls of the hose. 2. Frictional loss as the fluid has to flow over itself (internal resistance or shear). This is because the fluid moves faster through the center of the hose and slowesagainst the walls. 3. The restriction of flow due to the change of direction the air or fluid must take. 4. The volume of air or fluid the hose must carry in a given period of time. This is determined by the amount of back pressure in the system. 5. The actual weight of the air or fluid being carried in the hose. For instance, the elevation must be accounted for at the approximate rate of.5 p.s.i. per foot of lift based on water , i lb ;5 io i5 j, i5 i 45 sb CFMFREE AR BASE100 PSlG NPUT 100' LENGTHS WTH FTTNGS CFMFREE Ald 2. As the length of the hose increases the pressure drop increases. This drop is proportional through out the total length of the hose. 3. The conditions of the surface of the inner tube will greatly influence the pressure drop; a rough tube can cause as much as a 50% increase in pressure drop. j,*, '>\

2 11. HOSE CONSTRUCTON: The bndc constnction of?lost air and fluid hoses Ne comprised of the followlng parts: 1. TU L.. T ~ only U part in contact with the coating material. t is carefully selected to resist the solvent action of the coating under application temperatures and pressure. 2. CA~CASS... One or more layers of high tensile fabric or met01 braid bonded to the tube and jacketrequired to provide satisfactorily high working rmure and designed to provide maximum flexibility. 3. JACKET... Tho protective outer coverchosen to resist damage from abrasion and wear, oils and chem icals and atmospheric exposure ~ HOSE 1 ~ CONSDERATON A. When selecting an air hose consider the following points: 1. The volume of air that the hose must carry; this may be determined by totaling the air consumption (CFM) of all the air tools supplied by the hose at one time. See the manu facturers literature for amounts. This factor determines the inside diameter of the hose required. NOTE: Remember, the greater the volume (CFM) of air that must pass through the hose in a given time the greater the pressure drop will be. Below is a list of some typical air operated equipment and the approximate C.F.M. required air at 100 p.ai. Air Motor (agitator type). 68 CFM Airless Pump (one G.P.M.). 610 CFM Airless Pump (two G.P.M.) CFM Airless Pump (three G.P.M.) 3040 CFM Dusting gun (blow gun) CFM Low pressure Pump (light materials) CFM Low pressure Pump (medium materials) 1020 CFM LOW pressure Pump (heavy materials) CFM Pressure tank (any size) CFM Spray gun (home owner type) CFM Spray gun (production external mix) CFM Spray gun (production type internal mix). 510 CFM Spray gun (undercoating internal mix) CFM 2. The second factor in determining the inside diameter required is the total length. This length should be determined by measuring the distance between the input point of the air and the point of exit. f long distances are en counted, the reduction of the inside diameter in stages will he1 reduce pressure loss and lower the cost OF the hose over the entire length or by using a wipend. The charts below indicate the pressures drop in hoses for the following conditions: Average Compressor H.P. Requirement3 Gas Powerd 4to6HP 6to8 HP 6to8HP 8to12HP 12to18HP 25 to 60 HP Tool CFM Requirements a $ : L L 8 s AR HOSE SELECTON GUDE i L 0 n Based on Pressure Drop At 90 PS nput 5/16".D. Hose 3/8".D. Hose 112".D. Hose 314".D. Hose ( (71132) (71133) (71.134). 0 +e Cln %$ LL 00 m r U 0 s Note: Pressure loss exceeding 10 PS is excessive and unacceptable for normal conditions. The specific pressure loss through a hose is relative to the pressure and C.F.M. usage of the tool. 2

3 NOTE: For standard production spray gun applications, 5/16.D. for a maximumof 50 ft. is the recommended size. For pump applications, 3/8.D. should be used at a maximum length of 50 feet from the air supply to the pump. 3. The third factor in selecting an air hose is the systems working pressure. The working pressure of the hose should be selected according to the highest amount of pressure the system is capable of reaching. 4. The forth factor in the selection is the material used in the construction of the hose. This should be based on the nature of any liquids that may be introduced into the air hose, either intentionally or as a result of equipment wear, such as catalysts to cure a plastic coating or oil leakage from a compressor. 5. The flexibility requirements should be determined by how many times the hose is bent or moved and who will be holding the hose. For example, men or women spray operators. 6. CostHose should not be based on initial cost but on the benefits one will receive over the entire life expectancy of the hose. D. Basic Types of Air Hose Construction: Nonoil resistanta general purpose air hose recommended for spray guns, pumps and pressure pots, where oil is not present in the air supply. Oil resistantrecommended for industrial use and paint spray applications where resistance to entrained oil and external oil contamination is required. Nylon retrack hose permanently coiled nylon tubing for air service where it is desirable to have the air hose retract to an unobtrusive location. Air hose with a static grounding wire. Same as the oil resistant hose except it incorporates a copper grounding wire in the braid. Used mainly to prevent the possibility of fire due to static discharge and particularly helpful in minimizing a finish failure commonly referred to as mottling. V. FLUD HOSE A. When selecting fluid hoses.d., consider the following: 1. The volume of material to be carried by the hose in a given period of time. This may be determined by checking the volume of fluid required by the tool being used. 2. The viscosity of the material should be measured by instruments or compared to the way some substances move. For example: Liquid Description Centiposes Alcohol Water Kerosene Motor Oil 810 weight SAE Castor Oil Corn Oil Molasses Very thin Thin Medium Medium Heavy Heavy Very heavy Extra heavy.2 1.oo , The total length of the fluid hose from the point of discharge is another factor in determining the inside diameter required for the hose, To help in determining this, the following pressure loss chart is submitted for approximating this demension. Size of inside diameter required.d. of Delivery in Type of Approximate Hose Used F oz/minute Fluid Used Pressure Drop 114.D. 32 F oz/m (1 ) Water 3 psi 114.D. 32 F oz/m (2) DOP 76 psi 318.D. 32 F oz/m (1) Water.5 psi 318.D. 32 F oz/m (2) DOP 16 psi 318.D. 32 F oz/m (3) SAE 30 Oil 55 psi (1 ) Water was measured at 16 seconds in #2 Zahn Cup at 71OF. (2) Dioctylpthalate was measured at 26 seconds in a #2 Zahn Cup at 71oF. (3) SAE 30 Weight Oil was measured at 63 seconds in a #4 Ford Cup at 80 F. t must be remembered that if the hose has any bends in it or fittings, the pressure loss will be greater. f the fluid viscosity is greater than water the pressure loss will also be greater. f the viscosity is less then DOP the pressure loss will be less. Therefore, since most light consistency paints haveviscosities that fall between water and DOP, a 3/8.D. hose is recommended to minimize the pressure loss. When the viscosity is greater then DOP larger.d. hose should be selected. The approximate amount of material one can expect to find in various sizes of hose lengths might be of some interest and are therefore listed below: Size of Hose Length of Hose Contents in Gallons 1 14.D. 15 Feet.05 1 /4.D. 25 Feet D. 100 Feet D. 15 Feet 318.D. 25 Feet 318.D. 100 Feet The amount of material necessary to fill a hose is quite small, therefore, when storing fluid hose it would be good practice to keep the hose filed with a solvent which will not attack the tube of the hose. Keeping the hose wet prevents material from hardening in the inside, breaking loose, and later plugging the fluid nozzle or tip, Even though one may flush out a hose, a small amount of residue can remain behind and cause problems. 3

4 B. Consideration of the fluid hose construction: 1. Solvent resistance. Not all fluid hoses are able to resist all types of solvent and chemicals. Therefore, it is important to select the right fluid hose for each application. Check the manufacturers solvent resistance chart showing the suitability of various hoses to resist different chemicals and solvents. As an aide in selecting the proper fluid hose for the various solvents, one might consult the following chart. TYPES OF SOLVENTS, TH NN E R S, CATALYSTS Drying Oils A kyds (Mineral Spirits) (Naphtha) Phenolic Varnishes Epoxy Esters Coal Tars 1 Pkg. Urethanes (Naphtha Toluene Blend) Chlorinated Rubber Chlor. Rub. Zinc Rich Silicones "Hypalon" (Toluene) (Xylene) Phenolics Epoxies Epoxy Zinc Rich Vinyl Alkyds (Toluene MEK Blend) Vinyls Viny CAcrylics Polyesters Polyester Zinc Rich (MEK) (MBK) Lacquers 2 Pkg. Urethanes High Gloss Enamels (Ketone Ester Blend) PV Acetate Polyacryl ics Latex Zinc Silicates (Water Based) Amines (Epoxy and Phenolic Paints) MEK Peroxide (Polyester Coatings ). Nitric Acid (Epoxy Foams) Nater Based FLUD HOSE SERVCE AND SELECTON CHART TYPES OF FLUD HOSE AND TUBNG ROOM TEMPERATURE SERVCE: CONTNUOUS SERVlCl HEATED MATERAL SERVCE: CONTNL US SERVlCl Fluid Thiokol All Thiokol Nylon Solvent Synflex Electro High Pressurc Resistant Nylon Static Airless.. 0 B NTERMTTENT SERVCE 0 NTERMTTENT SERVCE 0 Airless H.P. Teflon BunaN Extrusion Wire Braid am 00 am an am 0 Polyethy lent Tubing a0 00 om am om am 0 0.0/@ 0 am 0 am am 0 am a om am i Aromatic Solvent Based a a Chlorinated Solvent Based a a a 4

5 2. The working pressure of the fluid hose should be greater than the highest possible pressure the system is capable of reaching. Hoses are normally rated according to the working pressure and the burst pressure. The type of carcass, and the number of braids required are determined by the working pressure. 3. The temperature of the material and the ambient (surrounding) conditions determines the material the tube and jacket are made of. (Note many solvents and fluids become more reactive when they are heated). 4. The flexibility requirements, 5. The weight of the hose. C. Types of fluid hoses available: 1. Fluid All; a nylon tube low pressure fluid hose with a rubber cover cabable of handling almost any type of fluid, 2. Standard thiokol fluid hose for most type paints, 3. Compar hose for fine finishing materials and heated paints (NOTE: Not recommended for water based paints)., 4. High pressure wire braided teflon hose for all types of airless applications. 5. Nylon high pressure hose with a static ground ing wire for most standard type airless applications, 6. Polyethylene catalyst hose (braided), is the only hose recommended to be used where atomized catalyst are injected into the air stream, 7. Extrusion high pressure hoses have an internal wire braid which is used with heavy mastic type materials, Fluid transfer (high pressure) hose similar to nylon airless hose except it does not incorporate a static grounding wire, Electrostatic hose (low pressure), a special composition material, is used in its construction so that it is able to conduct electricity, 10. Synflex nylon tubing (low pressure), a highly solvent resistant tubing with a maximum a mount of flexibility for nylon tubing, 11. Polyethylene tubing (low pressure) designed to be used with water type applications, 12. Retmct nylon hose (low pressure). NOTE: Gen erally used as an air hose but may be used as a fluid hose if desired. V. CONNECTONS A. Hose connections and fittings are available in various thread styles and sizes. The most common thread style used in the spray painting industry are either N.P.S. (National Pipe Straight) or N.P.T. (National Pipe Tapered). The N.P.S. style is the preferred thread used on most spray guns, air and fluid inlets. The N.P.T. thread style is the common type used for piping. The most common size connections and fittings used are 1/4, 3/8, 1/2, 3/4, and 1 in both the N.P.S. or N.P.T. stvle. n some sdecial instances Sometimes special types are used such as J..C. (joint industrial connection) which are high pressure hydraulic fittings. Airless fittings which are normally over a 1/4 and are used at high pressure are J..C. N PS NPT fo\ JC Not one type hose fitting will adapt to all types of hoses. Therefore, selection of the proper type connection necessary is dependent on the following: 1. The type of hose being used, 2. The size of the hose selectedits inside diameter and outside diameter, 3. Method of fastening the connection to the hose. 4. The thread style and type, fitting size, male or female type, required on the tool, accessories such as adaptors, nipples or valves etc., 5. The working pressure of the connection, 6. The chemical and solvent resistance of the wet parts of the connection. B. Some of the typical type connections that qre available are: 1. Reuseable connections are those connections which may be used over again when a hose has become unserviceable. They are available for all production type air and fluid hoses. This type of connection uses a compression ring which wedges the hose into a ferrule, binding the connection in the hose. This type connection is recommended for most conventional application. *Note: Without a compression ring. 2. Ferrule connections are used on low cost hose assemblies. They are not reusable. 3. Strap connections for standard medium pressure hose available in 1/2, 3/4, 1.D. they also require a special tool for mounting. Ei 1/8 might also be &ed. W 5

6 4. Clamp Screw Type reusable connections, used where the hose has an odd size outside diameter also used for low cost installations. D. Coupling or Reducer Coupling. This has two female ends which permits two pipes to be joined together, perhaps of the same size or different size. 5. Hose menders; a low pressure device designed to repair damaged hose by clamping the hose ends together after the damaged portion has been removed. E. Elbows, Street els or Swivel elbowsa fitting designed for creating a bend in the line. Standard types have two female threads, not necessarily the same size and are available in either a 45O or 90 bend, Street els are basically the same except one side has a male thread. V.FTTNGS Fittings are small miscellaneous items that are used in various ways to interconnect hoses, piping and equip ment to make up an air or fluid distribution system. A. NipplesDouble Male are fittings with a male thread on each end; these end threads are not necessarily the same size or style. Some nipples may incorporate a wrench hex in the center portion. They are used to: 1. Connect lengths of hose together, 2. Convert a female thread to a male thread, 3. To adapt one thread style to another. DOUBLE MALE NPPLE B. Adaptershave one male thread and one female thread, not necessarily of the same thread style or size. They are used for converting one male thread size or type to another. Available in either standard or high pressure. F. Tees and Crossesfor interconnecting a third or fourth line into a piping system. U V. VALVES Valves are used in a system to turn air and/or fluid supply on or off. A. The tapered plug valveuses matching tapers on a plug and seat to provide a seal, similar to a gas cock. Note: They have a tendency to freeze or stick when used with fluids. C. Swivel Adapter or Union is a connection which has either two female ends or one male and one female. Designed with a swivel joint, which will permit one to break into a system or add a piece of equipment without having to twist the line. B. Ball Valvesare the most efficient means of controlling air and fluid. They use a ball rotating in teflon seats to provide the following advantages: 1. A minimum restriction to the flow of air or fluid 2. Ease of actuation. They turn easily under full load pressure or no load pressure, 3. Wide range of interchangeable fittings for flexibility of application. Available in either standard pressure or high pressure types, 4. They can be connected to indicate direction of flow. 6

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8 X. NOTES OF CAUTON 1. Always know what kind of chemicals, solvents or thinners the materials contain so that the right type fluid hose and connections may be selected. 2. Familiarize yourself with the materials used in the construction of the hose that you are dealine with. Y 3. Never exceed the recommended working pressure or temperature of any hose. 4. Never use standard pressure hose or fittings for high pressure applications, 5. When working with high pressure airless hose, never bend the hose in LESS than a 4 radius, otherwise it will kink and may burst. 6. Check all connections to make certain they are tight before turning on the air or fluid supply system. Eye protection should also be used especially when using dangerous materials. 7. Always use proper tools when working with connections, such as an open end wrench, box wrench, flare or adjustable wrenches. Never use pliers, vise grips, or pipe wrenches. 8. Do not lose or overlook the compression ring or 2eeve from connections where this method is used to hold and seal the hose to the connection. 9. Always match proper pipe thread sizes and styles. 10. Never open partially a valve or use it for regulation. Always have it open or closed all the way. Disregarding this will cause the valve seats or stems to wear out prematurely, or wire draw. X. GLOSSARY OF COMMON TERMS FOR HOSE AND FTTNGS AR HOSEA rubber hose made especially for sup plying air to a spray gun or other airoperated equipment. Binks uses the color red to designate air hose and it comes in the following inside diameters: 1/4, 5/16, 3/8, 1/2, 3/4, and 1 inch. Brown is used to indicate an air hose with a static grounding wire. CENTPOSEA unit of viscosity, conveniently and approximately defined as the viscosity of water at room temperature. The following table of approximate viscosities at room temperature may be useful for rough comparison. Liquid Viscosity in Centipoises Water 1 Kerosene 10 Motor oil $10 weight SAE 100 Castor oil 1000 Corn oil 10,000 Molasses 100,000 C.F.M.Cubic Feed Per Minute which is a measurement of a volume of standard air measuring 12 x 12 x 12 passing a given point in one minute. COMPAR (Hot Lacquer Hose)A special fluid hose used with a plastic lining when hot spray work is to be done; never to be used with a water based material. HGH PRESSURE HOSE CONNECTONSUsed on a nylon high pressure hose for airless spraying. NSDE DAMETER (1.D.)The inside diameter of the tube, hose lining or fittings. J..C. CONNECTON (Joint ndustrial Commission Connection)These connections are generally used by hydraulic or electronic industries and have been used in some airless applications. OUTSDE DAMETER (0.D.lThe measurement a cross the outside diameter of the jacket of the hose. p.s.i. Pounds Per Square nch is a measure of energy or force above a vacuum. RETRAK HOSEA hose that is wound in a coil and will spring back into a compact size when released. This nylon hose is available in 1/4 and 318.D. t may be used for fluids too. STANLESS STEEL HGH PRESSURE BRADED HOSEUsed for airless applications and is more flexible than high pressure nylon and more solvent resistant. Will also withstand more abuse and has a longer life than the nylon high pressure type. STRAGHT PPE THREADSA standard thread system based on pipe sizes used by Binks for most air and fluid connections on spray equipment. Relies on matching tapered seats to provide a seal. STANDARD ARs defined as one cubic foot of air at a atmospheric pressure of 14.7 p.s.i., temperature of 68OF. and a humidity of 36%. STANDARD FLUD HOSEA rubber hose made especially for supplying material to a spray gun. Care must be taken in choosing a fluid hose with the proper tube so that the solvents used will not attack the inner lining. Binks supplies this hose in black and is available in the same sizes as the air hose. STATC GROUNDNG WREA wire built into a hose which is used to ground the spray gun so that there isn t an electrical charge built up in the spray gun or operator. SYNFLEX HOSEA nylon hose, mjky white in appearance, used to carry fluid and solvents which normally affect rubber hoses. Advantages are light weight, chemically inert, cleans easily, minimum pressure loss, translucent and low in cost. TAPERED PPE THREADSA standard thread system found in standard plumbing systems. Relies on interference of threads to provide a sealing surface. TWO BRADED CONSTRUCTONwhere two braids of reinforcement is woven around the tube giving the hose higher burst strength or working pressure rating. WRE DRAWA term used todescribe the process by which hydraulic erosion wears away a portion of a valve seat or stem. Binks Manufacturing Company W. Belmont Ave., Franklin Park, L Telephone (708) Printed in USA 3/89