TRAINING BULLETIN TOOLS 7 December, 1978 1. NOZZLE NOMENCLATURE AND IDENTIFICATION 1.1 A nozzle identification and nomenclature system is established to insure that issuance and recall of equipment as well as adaptation or utilization instructions for nozzles will be facilitated and/or understood. 1.2 One-piece nozzles, or the components of multi-piece nozzles, will be designated and marked by a letter or letters identifying the nozzle or part, followed by a number which will identify the specific F.D.N.Y. model; in some cases a size designation will be included. 1.3 Data Sheets, describing the specific item will be issued when new appliances are introduced into the department, or to describe existing equipment. Such Data Sheets will make up the Appendix to this bulletin. 2. DEFINITIONS* AND DESIGNATIONS 2.1 A nozzle is a hose line appliance that is either single unit or multi-unit, in that it is composed of one or more sub-assemblies. It is used to direct the flow of water increase the velocity or flow, or disperse the water in small droplets or fog** in various patterns. 2.2 The basic parts of any nozzle are described in this section. In addition, the appropriate Data Sheet will list pertinent technical data, including: Manufacturer Waterway size, Inlet and Outlet threads, Hydraulic characteristics, Overall dimensions, Weight, Operating instructions, etc. * Illustrations will supplement these definitions; specific minor terms are only defined on the illustrations. ** There is a technical difference between the term "fog" and "spray". For our purposes, all devices that produce dispersed streams will be termed "fog" unless specifically designated "spray". 1
2.2.1 SHUT-OFF (SO) Figure 1- That section of the nozzle that contains the water control valve. It is identified by the letters "SO". 2.2.2 TIP - in attachment usually connected to a SO, or a hose butt; it performs the basic function of the nozzle and is designed in various forms. The characteristics of Solid Stream tips and nozzles are determined by tip design. The patterns and flows of fog stream tips and nozzles are determined by special designs. A. SOLID STREAM TIPS are generally Stacked. 1. Stacked Tips for hand lines are limited to two individual tips. a- MAIN SOLID STREAM TIP (MST) [Figure 2] - is fitted with threads at its outlet orifice, is the first tip of the stack, and is attached directly to a SO. b- OUTER SOLID STREAM TIP (OST) [Figure 3] - does not have outlet orifice threads, and is threaded at its inlet for attachment to a MST to further reduce bore diameter. The 1/2" tip is a OST. B. FOG TIPS are fog producing devices. 1. FOG TIP (FT), Figure 4- the most common types have an outer rotating barrel which is used for stream adjustments and, in some models, as a shut-off. 2. Most FT's are classified as Combination Straight stream/ Fog devices. The straight stream is hollow and the fog patterns depend on adjustments permitted by the Outer Rotating Barrel. C. Other tips are designed for various specific functions and are generally named according to their purpose; i.e., foam pick-up, extension, low velocity fog, etc. Data Sheets will be issued detailing their nomenclature and identification, etc. 2.2.3 FOG NOZZLE (FN), Figure 5- is defined as a fog producing device that contains, addition to the Outer Rotating Barrel, a ball-type shut-off as an integral part of its assembly. 2.2.4 DUAL NOZZLE (DN), Figure 6- contains separate discharge orifices and permits selective discharge, usually by means of a shut-off with more than two positions. 2
2.2.5 Some other definitions are: A. OPEN NOZZLE, Figure 7- is basically a solid stream tip designed to be attached directly to the hose butt. It differs from MST in that no threads are provided at its outlet orifice. B. CONTROLLING NOZZLE- any nozzle which contains a mechanism for controlling the flow of water at the nozzle. C. WORKING NOZZLE- any nozzle carried attached to hose in the hose bed of the apparatus. 2.3 FTs AND FNs MAY BE OF VARYING DESIGN: 2.3.1 CONSTANT FLOW OR VARIABLE FLOW - These terms define what occurs to the amount of water being discharged when the pattern selection is changed. A. CONSTANT FLOW - Once a given flow had been established, a flow will remain constant and will not vary if the discharge pattern is changed. Because of this feature, member must be aware that the volume discharged may be less than required. B. VARIABLE FLOW - Once a given flow has been established, flow will vary if the discharge pattern is changed. For example, more water is generally delivered in the fog position than in the straight stream position. 2.3.2 CONSTANT PRESSURE OR VARIABLE PRESSURE - These terms define what occurs to the nozzle pressure when the amount of water being supplied to the tip/nozzle is increased or decreased. A. CONSTANT PRESSURE (Automatic)- Should be understood to mean, that the nozzle pressure remains practically constant within the operational limits of the automatic feature of the tip (for the FT-2, 65 to 105 PSI), as the water being supplied is increased or decreased. Changes in pattern selection will not affect nozzle pressure This type of tip automatically adjusts the orifice size, thus keeping the nozzle pressure practically constant. Consequently, the reach will also remain practically constant. Because of this feature members must be aware that the volume discharged may be less than required. A sure sign of this condition would be reduced nozzle reaction (easier handling), while the stream appears to remain unchanged. B. VARIABLE PRESSURE (Non Automatic) - Nozzle pressure will vary directly as the water being supplied is increased or decreased. Depending on nozzle 3
design, nozzle pressure may or may not be affected by chances in pattern selection. 2.4 Tips or nozzles that produce fog depend on two basic actions described as PERIPHERAL or IMPINGING. 2.4.1 Fog is developed in the Peripheral type (Figures 4 & 5) by directing a stream of water against a baffle which deflects the water through serrated teeth at the periphery, which action separates disperses water into fine droplets. 2.4.2 THE IMPINGING NOZZLE (Figure 6) includes a series of small orifices which cause multiple streams to impinge on each other. The impingement breaks the water into fixed, non adjustable fog pattern. 3. NOZZLE MAINTENANCE 3.1 All hose fittings equipment should be regularly examined and cleaned to insure that they are always in good condition and ready for immediate operational use. 3.2 A systematic program for this maintenance not only insures that equipment is maintained in firstclass condition at all times but also that personnel become thoroughly familiar with it and get to know exactly where each item is kept on the apparatus. This knowledge is essential if members are to operate quickly and efficiently at fire operations. 3.3 When cleaning nozzles, particular attention should be given to insuring that all moving parts operate freely; that any rough edges or projections which might damage the hose are smoothed or removed, and that residue from paint or polish is removed from places where it may tend to block holes, threads or passages, and thus reduce operating efficiency. 3.4 Nozzles should be washed out and thoroughly checked for any defects before being placed back in service following use. Nozzles should be washed in solution of soap and hot water. Submerge the nozzle and work the mechanism until free movement is obtained, then rinse in water. Nozzles should be examined after use and any obstructions removed. A. Special care must be taken to insure that there is no obstruction in the orifice between the baffle and the rim of fog tips, otherwise poor streams of fog will result. Also, combination SS/Fog devices shall be placed in straight stream position (turned to the right) at all times when stored on apparatus or in hose bed. This will avoid possible damage to the baffle. 4
December, 1978 B Tips depend for their efficiency upon the true circular opening of the outlet orifice and upon an undamaged lip, and care should be taken when cleaning them. C Particular attention must be given to the inlet orifice diameter of any of the solid stream tips to make certain it equals the outlet orifice diameter of the SO to which it is attached. If it is smaller and the lip of the inlet orifice projects as a sharp edge into the bore, the stream will be severely limited (coefficients of discharge may vary from normal.998 to.80 or worse). Units when discovering this condition, shall promptly forward the tip to Division of Repairs & Transportation to have the inlet orifice adjusted. Adjustment usually consists of chamfering (beveling) the lip to avoid a sharp projection into the waterway. 3.5 Nozzle/Tip couplings which, due to damage, cannot be connected without difficulty should be taken out of service until such time as they can be repaired or replaced. A faulty coupling left in service may well be the cause of delay in getting a vitally important line of hose to work on a fire. 3.6 Excessive force should not be used to tighten nozzle components or couplings as this may damage the washer and cause leakage. 3.7 A light coating of oil should be put on all couplings and moving parts after cleaning. 3.8 Officers supervising the operation of hose streams shall keep OST in their possession when they are removed from nozzles. Similarly, FT shall be in the officer's possession when not attached to a SO or hose butt. 3.9 Identifying letters and numbers placed on nozzles and components shall be stamped on the coupling along the hub, adjacent to the coupling lug. 3.10 Until conditions require removal, the OST (½" tip) shall always be attached to the nozzle. 3.11 Nozzles shall be carried in an accessible position on the apparatus, protected from damage. Neither the control handles of SOs and FNs, nor the shut-off valve itself shall be used for the purposes of holding or clamping nozzles to holders. 3.12 To prevent mechanical damage, nozzles should be handled with care. They should not be dropped or thrown aside. 3.13 When using a nozzle, care should be taken not to twist or bend control handles. Either of these conditions may prevent the control valve from opening fully or may permit the valve to go past the full opening. In both cases the bore would not be fully opened and the result would be a broken stream and/or reduced flow to the fire. 3.14 Nozzle mechanisms should work freely. If for any reason a control sticks, the nozzle should immediately be taken out of service and sent for repairs. It should never be necessary to 5
December, 1978 hammer a control handle or apply excessive torque, by hand or mechanically, to a rotating type control to make it operate. 6
3.15 Controlling nozzles will be tested annually in August and whenever deemed necessary in accordance with schedules established by Division Commanders as follows: A. Two lengths of hose (100') shall be stretched from the pumper, nozzle attached, water started and sufficient pressure developed to attain an effective stream. B. Shut offs shall be opened and closed several times as in normal operating procedures, and nozzles operated (MST, OST, FT) throughout their various positions and pressures. C. Nozzles found defective shall be removed from service and forwarded to the Repairs and Transportation Unit for necessary repairs. 3.16 New issue or repaired nozzles shall be tested in accordance with Section 3.15 before being placed in service. FIGURE 1 Typical Shut-Off (SO) 7
FIGURE 2 Typical Main Solid Stream Tip (MST) Hub Converging Cylindrical section section of bore of bore Washer space Inlet Orifice Diameter Outlet Orifice Diameter Coupling Female (generally 1 1/2 FDNY Thread) FIGURE 3 Typical Outer Solid Stream Tip (OST) Male threads are compatible with discharge outlet threads of 3/4, 15/16, 1 1/8, 1 1/4, MST Inlet Leather Washer Hub 1/2 Outlet Cylindrical section of bore 8
Rim FIGURE 4 Typical Comb. SS/FOG* Tip (FT) Baffle Serrated Teeth Tip may have raised (braille-like) Pattern indicators and/or click stops Outer Rotating Barrel Sleeve Coupling Lug (pin type) *Straight Stream/Fog Coupling - Swivel or non-swivel female base 1 1/2 or 2 1/2 thread Rim Baffle Nozzle may have raised (braille-like) pattern indicators and/or click stops FIGURE 5 Typical Comb. SS/FOG* Nozzle (FN) Serrated Teeth In some models rubber /plastic guard Outer rotating barrel Sleeve Integral shut-off Shut-off handle Coupling lug (pin type) *Straight Stream/Fog 9 Coupling swivel or non-swivel female base 1 1/2 or 2 1/2 thread
FIGURE 6 Typical Dual Nozzle (DN) TRIPLE ACTION HANDLE OFF Forward position FOG Middle position SOLID STREAM Back position Shut-off handle Swivel or non-swivel base 1 1/2 or 2 1/2 thread Solid stream orifice Impinging jet for high velocity fog Shut-off Tip removable if extension applicator (low velocity fog) is desired 10