Emergency Vehicle Ops: Review of Hydraulics and Pump Components

Pumps Refresher Course Session Reference:1 Topic:Review of Hydraulics and Pump Components Time Required: 3 hours Materials:Chalkboard Reference:Pump Operator Student Manual, Maryland Fire and Rescue Institute Preparation...


      a. primer - creates vacuum in casing for drafting operations

      b. auxiliary cooler – circulates water between pump and radiator

      c. Radiator fill - transfers water from pump to radiator

III . Hydraulics review (1-3)

A. Nozzle pressures

  1. Straight tip

      a. 50 PSI handlines

      b. 80 PSI master streams

  2. Fog tip - 100 PSI handlines and master streams

  3. Automatic nozzles - 100 PSI handlines

B. Friction loss principles

  1. Round flow to nearest 50 gallons

  2. Supply lines - based on 3-inch hose (using hand method)

      a. 3-inch hose - Q2 (in hundreds of gallons)

      b. 4-inch hose - Q2 (in hundreds of gallons) divided by 5

      c. 5-inch hose - Q2 (in hundreds of gallons) divided by 15

      d. 2-1/2-inch hose - Q2 (in hundreds of gallons) times 2

      e. If quantity is between hundreds, multiply lower and upper quantities together. For example, 350

          gallons, multiply 3 times 4 for a total of 12 PSI per 100 feet between for 3-inch hose. Convert

          for 2-1/2-, 4-, or 5-inch hose.

  3. Attack lines up to and including 2-inch, 30 PSI per 100-feet

  4. Devices - 10 PSI per device

  5. Elevation - .5 PSI per foot

C. Calculating friction loss

  1. Attack pumper EP = FL + D +/- EL + NP

  2. Supply pumper EP = FL + D +/- EL + 50 PSI

D. Pressure control devices

  1. Intake

      a. Intake relief valve

      b. LDH relief valve

Should be set no more than 20 PSI above the average water system pressure in response area

  2. Discharge

      a. Pressure governor

      b. Relief valve Should be set after lines are charged

E. Characteristics of hose*

                            Quantity of Water                  Weight of Water             Maximum Flow

                            (in gal.)                                   (in lbs.)                          (in GPM)

1-1/2-in.               9.00                                       75.15                             125

1-3/4-in.              12.25                                      102.29                           150

2-in.                     16.00                                      133.60                           200

2-1/2-in.               25.00                                      208.75                           250

3-in.                      36.00                                     300.60                           400

4-in.                      64.00                                     534.40                           800

5-in.                      100.00                                   835.00                           1,500

*Quantity and weight based on 100 feet of hose

Review:

Review of Hydraulics and Pump Components

   * Introduction to Fluids

   * Centrifugal Pump Components

   * Hydraulics Review