Firewater pump presentation ntt
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This document discusses fire pump system design according to NFPA 20 standards. It provides information on the purpose of fire pumps, acceptable pump types, sizing requirements, accessories, and operation. Fire pumps are designed to supply adequate water for sprinkler or standpipe systems by automatically starting when pressure drops and operating at 150% of rated capacity and 65% of rated head. Acceptable pump types include horizontal split case, vertical in-line, end suction, and vertical turbine configurations.
Firewater pump presentation ntt
- 1. PETROVIETNAM ENGINEERING J.S.C DESIGN-SELECTION FIRE PUMP SYSTEM
- 2. PETROVIETNAM ENGINEERING J.S.C FIREWATER PUMP NFPA20 Standard for the Installation of Stationary Pumps for Fire Protection Presented by: Nguyen Thanh Tin
- 3. PETROVIETNAM ENGINEERING J.S.C Purpose of a Fire Pump • To protect lives and properties against fire by supplying an adequate water supply to automatic sprinklers or standpipe systems • To meet building codes and insurance requirements
- 4. PETROVIETNAM ENGINEERING J.S.C Listing Authorities • Underwriters Laboratories (UL) • Factory Mutual Research Corporation (FM)
- 5. PETROVIETNAM ENGINEERING J.S.C Codes and Standards • NFPA Philosophy – A fire pump system should operate irrespective of any damage it may cause to itself – No element of the system under emergency conditions should: • Prevent a fire pump from turning on • Cause a fire pump to turn off – Changes to the code must be substantiated by data or experience (actual scenarios)
- 6. PETROVIETNAM ENGINEERING J.S.C Water Supply – Where fire pumps are installed on a city main, a fire flow test should be performed to determine minimum and maximum supply pressures as well as suitability of supply for the fire protection system – Where adequate city supply water is unavailable, a suction tank or pit should be installed – Tank sizing must consider 150% of the fire pump rated flow – Total water requirements are defined in NFPA13 (Sprinkler Systems), NFPA14 (Standpipe Systems), NFP A15 (Spray or Mist Systems), Mains)
- 7. PETROVIETNAM ENGINEERING J.S.C Pump Requirements “Centrifugal fire pumps shall be listed for fire protection service.” “Pumps shall furnish not less than 150% of rated capacity at not less than 65% of total rated head. The shutoff head shall not exceed 140% of rated head for any type pump.”
- 8. PETROVIETNAM ENGINEERING J.S.C Pump Requirements 100% 150% 140% 100% 65% %Rated Head %Rated Flow Max Shutoff Head
- 9. PETROVIETNAM ENGINEERING J.S.C Pump Sizing “A stationary pump for fire protection should be selected in the range of operation from 90 percent to 150 percent of its rated capacity. The performance of the pump when applied at capacities over 140 percent of rated capacity can be adversely affected by the suction conditions. Application of the pump at capacities less than 90 percent of the rated capacity is not recommended. The selection and application of the fire pump should not be confused with pump operating conditions. With proper suction conditions, the pump can operate at any point on its characteristic curve from shutoff to 150 percent of its rated capacity.”
- 10. PETROVIETNAM ENGINEERING J.S.C Pump Sizing 100% 150% 100% Head Flow Pump Design Flow 90% Pump Rated Flow
- 11. PETROVIETNAM ENGINEERING J.S.C Pump Requirements • FM & UL require that fire pumps have packing seals • Packing requires periodic adjustment and replacement as it hardens over time • The packing gland should be tightened until the seal leaks 30 drips per minute • If the gland is tightened to much, the seal receives no lubrication and will burn
- 12. PETROVIETNAM ENGINEERING J.S.C Allowable Pump Types – Horizontal Split Case – Vertical In-Line – End Suction – Vertical Turbine
- 13. PETROVIETNAM ENGINEERING J.S.C Horizontal Split Case Fire Pumps
- 14. PETROVIETNAM ENGINEERING J.S.C HSC Fire Pumps • BENFITS – Available in a wide flow and head range – Serviceable without disturbing piping or driver – Available in electric or diesel drive • DRAWBACKS – Large floor space requirement – Restricts mechanical room layout due to direction of rotation – More costly – More difficult to service
- 15. PETROVIETNAM ENGINEERING J.S.C Vertical In-Line Fire Pumps
- 16. PETROVIETNAM ENGINEERING J.S.C VIL Fire Pumps • BENEFITS – Compact – Serviceable – Reliable – Cost Effective • DRAWBACKS – Only available up to 1500GPM – Electric Drive Only – Requires suction strainer
- 17. PETROVIETNAM ENGINEERING J.S.C End Suction Fire Pumps
- 18. PETROVIETNAM ENGINEERING J.S.C End Suction Fire Pumps • BENFITS – Moderate floor space requirement – Flexibility in mechanical room layout – Available in electric or diesel drive – Serviceable • DRAWBACKS – Only available up to 1500gpm – Single suction design limits hydraulic efficiency
- 19. PETROVIETNAM ENGINEERING J.S.C Vertical Turbine Fire Pumps • Used where a flooded suction cannot be maintained • Underground water sources or below ground tanks with above ground pump room
- 20. PETROVIETNAM ENGINEERING J.S.C Vertical Turbine Fire Pumps • BENFITS – Will operate under suction lift – Available in electric or diesel drive – Available over wide flow and head range • DRAWBACKS – More costly – More difficult to service and install
- 21. PETROVIETNAM ENGINEERING J.S.C Typical Application Wet Pit - Electric Motor Driver
- 22. PETROVIETNAM ENGINEERING J.S.C Typical Application Wet Pit - Diesel Engine Driver
- 23. PETROVIETNAM ENGINEERING J.S.C NFPA Required Pump Accessories Suction & Discharge GaugesAir Release Valve Pressure Relief Valve
- 24. PETROVIETNAM ENGINEERING J.S.C NFPA Required Pump Accessories • Suction gauge must be of the compound type (capable of reading negative pressure or vacuum) • Discharge gauge must read two times the working pressure of the pump and not less than 200psi
- 25. PETROVIETNAM ENGINEERING J.S.C Air Release Valve • 1/2” Air Release Valve is required • Exception: top centre-line discharge end suction and vertical fire pumps
- 26. PETROVIETNAM ENGINEERING J.S.C Automatic Air Release and Pressure gauges
- 27. PETROVIETNAM ENGINEERING J.S.C Circulation relief valve • A circulation relief valve allows a small amount of water to discharge from the pump to keep the fire pump from overheating when operating at no flow or very low flows.
- 28. PETROVIETNAM ENGINEERING J.S.C Relief Valve • 3/4” up to 2500usgpm • 1” over 3000usgpm • Should be set between the maximum suction pressure and minimum suction pressure plus the closed valve pressure of the pump • Piped before the fire pump dischar ge check valve
- 29. PETROVIETNAM ENGINEERING J.S.C Eccentric tapered reducer at suction inlet • When the pump suction pipe is larger than the pump suction flange, an eccentric tapered reducer is required to minimize the possibility of air pockets forming at the pump suction.
- 30. PETROVIETNAM ENGINEERING J.S.C Isolation Valves • Suction OS&Y Gate Valve • Discharge Butterfly Valve • Both must be supervised • Discharge Butterfly Valve Installed after “Test Tee” and pressure sensing line
- 32. PETROVIETNAM ENGINEERING J.S.C Hose Valve Systems – Provides testing means – Sized by pump rated capacity – There are hundreds of different thread types depending on jurisdiction - type should be specified on projects
- 33. PETROVIETNAM ENGINEERING J.S.C Flow Meters – Does not replace a hose valve system – Flow meters must be listed for fire protection service – Gauge reading is a minimum of 175% the pump rated flow – Provides a testing means without wasting water – Flow meter is installed in bypass back to suction – Must be installed with isolation valves per manufacturer’s specifications – RULE OF THUMB: Annular Type - 10Ø upstream - 5Ø downstream Venturi Type - 7Ø upstream - 5Ø downstream
- 37. PETROVIETNAM ENGINEERING J.S.C Main Relief Valves and Waste Cones – Sized by pump rated capacity – Spring or pilot operated – Waste cone provides visibility of flow through the valve – When it is used: 1) Diesel driven systems 2) Electric systems ???
- 38. PETROVIETNAM ENGINEERING J.S.C Main Relief Valves and Waste Cones – Recommended on all diesel driven systems – Not required on diesel if maximum supply pressure plus 1.21 x closed valve pressure does not exceed system pressure rating – NFPA allows piping back to suction - NOT recommended – Relief valve should be set below maximum pressure rating of the system
- 39. PETROVIETNAM ENGINEERING J.S.C NFPA Fitting Sizing Piping, Relief Valves, Metering Devices, and Hose Valves should be sized according to Table 2-20 on Page 20-13.
- 40. PETROVIETNAM ENGINEERING J.S.C NFPA Required Pump Accessories Fire Pump Rating GPM (L/s) Suction Size (in.) Discharge Size (in.) Relief Valve Size (in.) Relief Valve Discharge (in.) Flow Meter Size (in.) Number & Size of Hose Valves Hose Valve Manifold Size (in.) 25 (95) 1 1 ¾ 1 1¼ 1 - 1½ “ 1 50 (189) 1½ 1¼ 1¼ 1½ 2 1 - 1½ “ 1½ 100 (379) 2 2 1½ 2 2½ 1 - 2½ “ 2½ 150 (568) 2½ 2½ 2 2½ 3 1 - 2½ “ 2½ 200 (757) 3 3 2 2½ 3 1 - 2½ “ 2½ 250 (946) 3½ 3 2 2½ 3½ 1 - 2½ “ 3 300 (1136) 4 4 2½ 3½ 3½ 2 - 2½ “ 3 400 (1514) 4 4 3 5 4 2 - 2½ “ 4 450 (1703) 5 5 3 5 4 2 - 2½ “ 4 500 (1892) 5 5 3 5 5 2 - 2½ “ 4 750 (2839) 6 6 4 6 5 3 - 2½ “ 6 1000 (3785) 8 6 4 8 6 4 - 2½ “ 6 1250 (4731) 8 8 6 8 6 6 - 2½ “ 8 1500 (5677) 8 8 6 8 8 6 - 2½ “ 8 2000 (7570) 10 10 6 10 8 6 - 2½ “ 8 2500 (9462) 10 10 6 10 8 8 - 2½ “ 10 3000 (11,355) 12 12 8 12 8 12 - 2½ “ 10
- 41. PETROVIETNAM ENGINEERING J.S.C Pressure Maintenance Pump (Jockey) • Every system has a normal leakage rate that will result in a pressure drop • Jockey Pump will maintain the pressure in the system • This will prevent the main fire pump from starting for minor leaks
- 42. PETROVIETNAM ENGINEERING J.S.C Jockey Pumps Jockey (pressure maintenance) pumps and jockey controllers need not be listed for fire protection service. “The primary or standby fire pump shall not be used as a pressure maintenance pump.” A jockey pump should be sized such that it CANNOT meet the flow demand of a single sprinkler fixture.
- 43. PETROVIETNAM ENGINEERING J.S.C Jockey Pump Sizing • Jockey pumps should be sized for 1% of the flow of the main fire pump • Jockey pumps should be sized to provide 10psi more pressure than the main fire pump • Jockey pump should be sized so that it cannot meet the demand of the lowest flow fire protection fitting in the system
- 44. PETROVIETNAM ENGINEERING J.S.C Jockey Pump Sizing
- 45. PETROVIETNAM ENGINEERING J.S.C Fire Pump Operation – Fire pumps are designed to start on a pressure switch setting – Some fire pumps can be started automatically based on a deluge valve opening, or a remote signal – The pressure sensing line is the lifeline for the fire protection system
- 46. PETROVIETNAM ENGINEERING J.S.C Fire Pump Operation – Pressure switches should be rated for maximum pressure conditions – Jockey pump and fire pump sensing lines must be separate
- 47. PETROVIETNAM ENGINEERING J.S.C Fire Pump Operation
- 49. PETROVIETNAM ENGINEERING J.S.C CONTROLLER STARTING METHOD 600 % of Full Load Current Full speed 390 252 200 FULL VOLTAGE PRIM. RESISTOR PART WINDING AUTO- TRANSFORMER WYE DELTA FULL LOAD CURRENT 420 100
- 50. PETROVIETNAM ENGINEERING J.S.C DIESEL CONTROLLERS • Serve Three Basic Functions: • Start the Diesel Engine in an emergency • Monitor the Operation and Condition of the Diesel Engine • Keep the batteries charged
- 51. PETROVIETNAM ENGINEERING J.S.C DIESEL CONTROLLERS • Diesel Can be Started by Three Methods: • Pressure Switch (In the Automatic Mode) • Pressure Switch (In the Test Mode) • Manual Cranking (In the Automatic or Manual Mode) • Starting sequence: • Alternating cranking sequence • Six cranks every 30 seconds until diesel starts • If diesel fails to start, an alarm is activated
- 52. PETROVIETNAM ENGINEERING J.S.C DIESEL CONTROLLERS • Diesel Can be Stopped by Two Methods: • Manually by Pushing the Stop Button • Automatically after 30 minutes during weekly test • Overspeed shutdown: • A diesel fire pump will shut down in an emergency condition if the diesel operates mor e than 20% faster than the rated speed
- 53. PETROVIETNAM ENGINEERING J.S.C DIESEL CONTROLLERS • Diesel Controller Alarms • Battery and Charger Failures • Diesel operating condition (High Coolant Temperature, Low Oil Pressure, Overspeed, Failure to Start) • Contacts for remote indication of alarm conditions • Optional Pump Room Alarms (Low suction pressure, flow meter on, Main Relief Valve open, Low/High Pump Room temperature, Low fuel level, Others )
- 54. PETROVIETNAM ENGINEERING J.S.C DIESEL CONTROLLERS • Battery Charging Systems: • One charger for each set of batteries • Chargers are capable of fully charging the batteries in 24 hours • Batteries remain in an overcharged condition
- 55. PETROVIETNAM ENGINEERING J.S.C Pump Maintenance • Pump acceptance tests are defined in NFPA20 Chapter 11 • Inspection and maintenance are defined in NFPA25 Chapter 5 • Seals and bearings are the highest maintenance item for a pump • The packing should be checked and adjusted each time the pump is tested • As fire pumps do not run often, bearings should be checked for cleanliness and to ensure that adequate oil or grease has been applied (depending on the type of bearing) • Motor bearings should also be checked