background image

D&RGW K-28 COAL FIRED MANUAL

6

pump is sized to pump water in excess to the needs of the engine, and given time, will fill the boiler to its maxi

-

mum capacity. During those times the locomotive is stopped and the blower is on, makeup water needs to come 

via the tender pump.

Maximum water level is not critical, but should not exceed the bottom edge of the top nut of the water gauge. Over 

filling the boiler results in the engine priming, or passing water to the cylinders, and can be noticed by a spray or 

mist of water coming from the cylinder exhaust or blower stream exiting the smokestack. A more detailed discus-

sion of maintaining water level will be presented later in these instructions.

Coal Burning Processes

The combustion of coal in a firebox, and using the derived energy for steam production, is not a simple process. 

Coal is a complex material and its combustion is intricate. Coal, a mineral compound, contains, depending upon 

its specific type and source, various quantities of moisture, hydrocarbon volatile, ash, sulphur and fixed carbon . 

Coal needs a significant amount of heat to initiate and maintain combustion as well as a continuous supply of oxy

-

gen. Coal combustion takes two avenues. The first avenue takes place at a relatively low temperature and results 

in the combustion of the volatile hydrocarbon components. As fresh coal is added to the top of the burning bed of 

coal on the grates, the volatile hydrocarbons are gasified and driven off, burning in the space above the coal bed 

and producing hot flue gases that transfer their heat to the firebox, tubes and flues by convection, with minimal 

radiant energy. The second stage involves the fixed carbon portions of the coal bed situated on the grates.

The fixed carbon in the presence of a significant supply of oxygen, burns at a high temperature, becoming incan

-

descent in the process. This second process produces considerable amounts of radiant energy as well as ad-

ditional hot flue gases. The sulphur component, which is relatively small, also bums producing a corrosive in the 

form of sulphur dioxide which, in the presence of moisture, becomes sulphuric acid. The ash, or non-combustible 

portion, composed mostly of clay, remains behind to form clinker, clog grates, drop into the ash pan and be de-

posited in the smoke box.

In small scale locomotive boilers the heating surface apportionment between the fire tubes and the firebox, 

coupled with the small diameter of the tubes and their relative short length, generally favors the firebox for absorb

-

ing the energy of combustion . Most of the heat value in coal is contained in the fixed carbon portion , and since 

the fixed carbon portion combust with a high level of incandescence, this energy is readily transferred to the boiler 

radiantly. This results in the firebox being the major contributor to the steaming capacity of the boiler.

The combustion of both the volatile and the fixed carbon portion takes considerable amounts of oxygen. This 

necessitates that the bed of burning coal have a sizeable amount of air passing through it to maintain combustion. 

This air is provided by the exhaust nozzle and a separate blower, both located in the smoke box. The nozzle, as 

the engine runs , and the blower when it is stationary, reduce the pressure in the smoke box which induces air to 

be drawn up through the grates and burning bed of coal, through the tubes and flue, and out the stack.

The main requirement for this to take place, is for the air to have a free and unobstructed passage through the 

bed of coal, and that the coal be evenly spread across the grates. Any obstruction to the flow of air or lack of 

forced draft will cause the fire to go out . As well as obstructions, if there are large holes in the coal bed that allow 

air to circumvent passage through the burning portions of coal, combustion will be reduced . This is true also with 

leaving the firebox door open.

How you fire and run your locomotive needs to take into account how coal burns. The frequency of stoking , the 

quantity of coal stoked , how it is spread on the grates, as well as the quality of the coal , will all have considerable 

impact on how your locomotive performs . The specifics of coal firing will be covered in detail further on in these 

instructions.

Содержание D&RGW K-28 COAL FIRED

Страница 1: ...D RGW K 28 COAL FIRED INSTRUCTION MANUAL Instructions Provided by Pikes Peak Locomotive Works ACCUCRAFT TRAINS 33268 CENTRAL AVE UNION CITY CA 94587 TEL 510 324 3399 FAX 510 324 3366 WWW ACCUCRAFT COM...

Страница 2: ...eal wood NOT BRIQUET charcoal Available from gourmet cooking stores barbeque supply stores and some home improvement centers Cowboy Brand barbeque charcoal Cowboy brand barbeque charcoal available fro...

Страница 3: ...each run is highly recommended with special attention to the eccentric ram and driving yoke of the axle pump AFTER RUN BRUSHING To clean off the light dusting of ash and cinders following a run we use...

Страница 4: ...m done The functioning water level of a butane locomotive with its usual single flue located along the bottom of the boiler is less critical than that of a coal fired boiler with a crown sheet The cro...

Страница 5: ...your locomotives boiler and how it behaves The boiler in your locomotive duplicates a full size boiler in all aspects including significant areas of flat surface Construction includes 8 fire tubes an...

Страница 6: ...producing a corrosive in the form of sulphur dioxide which in the presence of moisture becomes sulphuric acid The ash or non combustible portion composed mostly of clay remains behind to form clinker...

Страница 7: ...ng The Welsh steam coal available from Coles Power Models falls into this category Although it bums relatively fast and needs more continuous stoking than other coals it burns without much ash no smok...

Страница 8: ...r Also available is Green Velvet Steam Cylinder Oil We have not tried this oil and have no opinion as to its suitability but it is being used by various ride on 7 5 inch gauge builders It can be purch...

Страница 9: ...condensed water remaining after a run Your lubricator is fitted with a drain to use for removing the condensate at the end of a run but this makes measuring it difficult The best way to accomplish th...

Страница 10: ...but only after a good bed of coals is established If you are using the Cole s Power Models product it will come in a bucket with pieces ranging from pea sized on up to the a lump twice the size of the...

Страница 11: ...f running time Water can now be added to the tender It will hold approximately 2 quarts and should be filled to the bottom of the hatch Once the tender is full of water you can clear the pump feed lin...

Страница 12: ...best By now your locomotive should be completely converted over from the startup charcoal and you can begin a regular rhythm of stoking checking the water gauge and occasionally adding water to the t...

Страница 13: ...h pan Place engine on table so that front truck and rear truck are on newspaper or paper towel Open hinged Smoke box door and using the flue brush thoroughly brush out the tubes and flue Use computer...

Страница 14: ...e fired again within 60 days you may leave the boiler with water at or above the red line on the gauge glass Store engine and tender in a dry environment Do not wrap in plastic condensation can form w...

Страница 15: ...ates the 2 mm stainless steel socket headed cap screws although we provide one for your use replacements can also be purchased at your Sears store The wrench set best suited for maintaining your locom...

Страница 16: ...nnecting Rod Pin Valve Gear and Valve Guide Reverse Rod Check That Grates are Clean and Installed 3 Place Locomotive on Track and Prep Check That Smoke box is Clean Close Door Drain and fill Lubricato...

Страница 17: ...ghtly to compensate for increased pressure When Pressure Reaches 70 Lbs Start Engine Check Coal Level Add level with bottom of door if needed Open Cylinder Drains Check that Bypass Valve is Closed Pla...

Страница 18: ...urn out while the engine continues to run When pressure drops to about 45 lbs Run engine onto cooling track Close throttle close lubricator valve close blower valve Open firebox door Open gauge glass...

Страница 19: ...ont engine and run ning gear and firebox Wipe off residue with paper towels and let engine air dry for a while Lightly spray running gear with WD 40 and wipe excess off with a paper towel Reassemble s...

Страница 20: ...e shovel or the hook end of the Fire Pick Il also runs cool enough to be opened and closed by hand The door has two small air holes in it that allow the operator to see the intensity of the fire The w...

Отзывы: