webinar-overview of fire pumps and water storage tanks

Overview of Fire Pumps and Water Storage Tanks Webinar

1Proprietary Presentation by Koffel Associates, Inc.

M. Steven Welsh, P.E.

Registered FPE

Koffel Associates, Inc.

www.koffel.com

[email protected]

Overview of Fire Pumps and Water Storage Tanks

Expertly Engineering Safety From Fire

Outline

Introduction

Fire Pump Design

Water Tank Design

Coordinating with other trades

Deficiencies

Koffel Services

Consulting

Design

Construction Period Services



My Background

Graduated with Bachelor of Science in Fire Protection Engineering from the University of Maryland at College Park in 2002.

Worked in the United Kingdom.

Worked for sprinkler contractor.

Employed with Koffel for 9 years.

Registered engineer (DE and MD)

Standards

NFPA 20, Standard for the Installation of Stationary Pumps for Fire Protection, 2013 Edition

NFPA 22: Standard for Water Tanks for Private Fire Protection, 2013 Edition

Typical Arrangement



Typical Arrangement

Exterior Fire Pump House and Tank

Typical Arrangement

Electric Centrifugal (horizontal split-case)

Typical Arrangement

Centrifugal Cutaway: pressure is developed principally by an action away from center.



Typical Arrangement

Parts of Packing

Typical Arrangement

Vertical In-line

Typical Arrangement

Diesel



Typical Arrangement

Vertical Turbine

Typical Arrangement

Vertical Turbine Cutaway

Typical Arrangement

Packaged System



Typical Arrangement

Bolted Steel

Typical Arrangement

Bolted Steel

Typical Arrangement

Pressure Tank



Typical Arrangement

Fiberglass-Reinforced Plastic Tanks

New vs. Existing

New Work

Existing Document existing conditions

Check servicing

Sizing Pumps and Tanks

Sprinklers

Standpipes

Special hazards

Firefighting





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.

Fire Pump Design



Fire Pump Design

Fire Pump Design

Bypass: Where the suction supply is of sufficient pressure to be of material value without the pump, the pump shall be installed with a bypass [4.14.4.1]

Fire Pump Design

Elbows and tees with a centerline plane parallel to a horizontal split-case pump shaft must 10 times the suction pipe diameter away from the pump’s suction flange [4.14.6.3]

X



Fire Pump Design

Fire Pump Design

Fire Pump Design

Elbows and tees with a centerline plane perpendicular to the horizontal split-case pump shaft are permitted at any location



Fire Pump Design

X

Fire Pump Design

Strain Relief: where the pump and its suction supply are on separate foundations with rigid interconnecting pipe, the pipe must be provided with strain relief [4.14.6.5]

Valves: outside screw and yoke (OS&Y) gate valve must be installed in the suction pipe [4.14.5]

Fire Pump Design



Fire Pump Design

Fire Pump Design

Fire Pump Design



Fire Pump Design

Fire Pump Design

Eccentric tapered reducer or increaser required at pump suction to avoid air pockets [4.14.6.4 ]

Fire Pump Design

Eccentric tapered reducer



Fire Pump Design

Eccentric tapered reducer

Fire Pump Design

Fire Pump Design

No requirement at pump discharge, typically concentric



Fire Pump Design

Pressure gauges [4.10]

Fire Pump Design

Circulation Relief Valve: installed on the discharge side of the pump before the discharge check valve, valve shall provide flow of sufficient water to prevent the pump from overheating when operating with no discharge, nominal size of 0.75 inch(19 mm) [4.11]

Fire Pump Design



Circulation Relief Valve:

Fire Pump Design

Fire Pump Design

Check Valve: required in the pump discharge assembly. [4.15.6]

Fire Pump Design

Gate or butterfly valve: required in the pump discharge assembly. [4.15.7]



Fire Pump Design

Pressure Maintenance Pumps: sized to replenish the fire protection system pressure due to allowable leakage and normal drops in pressure, no listing required [4.25]

Fire Pump Design

The jockey pump stop point should equal the pump churn pressure plus the minimum static supply pressure.

The jockey pump start point should be at least 10 psi (0.68 bar) less than the jockey pump stop point.

The fire pump start point should be 5 psi (0.34 bar) less than the jockey pump start point.

Fire Pump Design

100 psi pump at churn, 50 psi minimum from city

Jockey pump stop = 100 psi + 50 psi = 150 psi

Jockey pump start = 150 psi − 10 psi = 140 psi

Fire pump start = 140 psi − 5 psi = 135 psi



Fire Pump Design

Fire Department Connection

Fire Department Connection

Fire Pump Design

Fire Pump Design

Test Header



Fire Pump Design

Fire Department Connection and Test Header

Fire Pump Design

Maximum Pressure for Centrifugal Pumps [4.7.7]

The net pump shutoff (churn) pressure plus the maximum static suction pressure, adjusted for elevation, must not exceed the pressure for which the system components are rated.

Fire Pump Design

Maximum Pressure for Centrifugal Pumps [4.7.7]

Variable speed pressure limiting control drivers, as defined in this Standard, shall be acceptable to limit system pressure.



Fire Pump Design

Pressure Regulating Devices: No pressure regulating devices must be installed in the discharge pipe [4.15.10]

Exceptions

Fire Pump Design

Pressure Regulating Devices, exceptions:

Where a diesel engine fire pump is installed and where a total of 121 percent of the net rated shutoff (churn) exceeds system rating

Where an electric variable speed pressure limiting controller or a diesel pressure limiting driver is installed

Fire Pump Design

Nameplate [4.9]



Fire Pump Design - Diesel


Requires sprinkler protection [4.12.1.3]

Enclosing diesel engine pump drivers and day tanks


Exhaust Piping: [11.5.2]

Each pump engine must have an independent exhaust system.

A flexible connection with a section of stainless steel, not less than 12 in. (305 mm) in length must be made between the engine exhaust outlet and exhaust pipe.

The exhaust pipe shall be covered with high-temperature insulation or otherwise guarded to protect personnel from injury.

Exhaust pipes passing directly through combustible roofs or walls must be guarded at the point of passage





Exhaust Discharge Location: [11.5.3]

Exhaust from the engine shall be piped to a safe point outside the pump room and arranged to exclude water.

Exhaust gases shall not be discharged where they will affect persons or endanger buildings.

Fire Pump Design

Flow Meter



Fire Pump Design

Vertical Turbine Pump:

Fire Pump Design

Suction Screening: where the water supply is obtained from an open source such as a pond or wet pit, the passage of materials that might clog the pump shall be obstructed [4.14.8.1]

Tank Design



Tank Design

OSHA-compliant (29 CFR 1910) standard railing shall be placed around the roof manholes and other accessories that require access [4.14.1.1]

Tank Design

Tank Design

Where the steel roof is essentially airtight, there must be a substantial vent above the maximum water level [4.15.1]



Tank Design

Tank Design

Water-Level Gauge: “suitable design” [14.1.8]

Tank Design

Water-Level Gauge: “suitable design” [14.1.8]



Tank Design

Controlling Valve: [14.2.12]

Tank Design

Anti-Vortex Plate Assembly [14.2.13]

Tank Design

A permanent pipe connected to a water supply shall be provided to fill the tank [14.4.1]

The means to fill the tank shall be sized to fill the tank in a maximum time of 8 hours [14.4.2]



Tank Design

Overflow: the overflow pipe shall be of adequate capacity for the operating conditions and shall be of not less than 3 inches (75 mm) [14.6]

Tank Design

Tank Riser Drain: A drain pipe of at least 2 inch (50 mm) must be connected into the tank discharge pipe near its base [14.7.4]

Tank Design - Heating

Tanks that are subject to freezing shall be heated [16.1.1]

The heating system must be of such capacity that the temperature of the coldest water in the tank or tank riser, or both, is maintained at or above 42°F (5.6°C) during the coldest weather



Tank Design - Heating

Coordination with Other Trades

Fire-Resistive Construction [NFPA 20, 4.12]

2-hour High-rise building

Not full sprinkler protected.

Outdoor: 50 feet (15.3 m) away from any fire exposures

Otherwise, 1-hour


Ventilation for diesel fire pumps shall be provided for the following functions: [11.3.2.1]

To control the maximum temperature to 120°F (49°C) at the combustion air cleaner inlet with engine running at rated load

To supply air for engine combustion

To remove any hazardous vapors

To supply and exhaust air as necessary for radiator cooling of the engine when required




Fire alarm must monitor for the following supervisory signals: [NFPA 20, 10.4.7.2.2]

Fire Pump Running

Loss of Phase

Phase Reversal

Connected to alternate source (if applicable)

Nothing else is required to be supervised

Jockey Pump running should not be monitored


Power [NFPA 20, 9.2]

A normal source of power from a continually available source

Must be reliable

Dedicated source

Identifiable and remote disconnecting means


Structural for tanks

Dead Load

Live

Wind

Snow




Drainage [NFPA 20, 4.12.7]

Floors must be pitched for adequate drainage of escaping water away from critical equipment such as the pump, driver, controller, and so forth.

Must discharge to a frost-free location.

Fire Pump Design

Deficiencies

Corrosion and damage packing



Deficiencies

Parts of Packing

Deficiencies

Damaged packing and improper packing drainage

Deficiencies

Fire pump based not secure



Deficiencies

Fire pump is dirty

Deficiencies

Fire pump is dirty

Deficiencies

No drain for circulation relief valve



Deficiencies

Rock in impeller

Deficiencies

No service clearance for controller, 3 feet [NFPA 70]

Future Questions….

Join our LinkedIn Discussion Groups Life Safety Code

People can join the group and submit their questions or

People can email [email protected] and submit anonymously

Smoke Management

Proposed Changes to the IBC

Ask the Expert FAQ.Koffel.com



Thank You

M. Steven Welsh, P.E.Registered Fire Protection Engineer

www.koffel.com

[email protected]

410-750-2246

Follow us on LinkedIn

Expertly Engineering Safety From Fire

webinar-overview of fire pumps and water storage tanks

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