Steam Engine Specifications

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Main > Energy > Steam Engine


Summary[edit]

  • Deliverable: a one cylinder prototype module with scalability, to constitute a single stage of a stageable system (compound or 3 stage) which uses the same module that is scaled to make other stages
  • System consists of cyliner, crank arm, mechanical valve, automatically adjusted cutoff ratio, and constitutes a Steam Engine Construction Set
    • Cutoff ratio controlled by closed loop electronic feedback with some type of linear actuator
  • Applications to stationary, mobile, and solar power

Cost-Related Features[edit]

  • Lowest materials cost for a given performance
  • Simplest to fabricate, therefore lowest fabrication cost
  • Advanced techniques of fabrication utilized only when necessary to achieve cost
  • Fabrication tooling preferably simple, but secondary to fabrication cost
  • Uses commonly available parts
  • Replicable
  • Materials cost of $50/hp

Materials Calculations[edit]

  • 20 pounds of weigh per horsepower

Steel weights .2833 pounds per cubic inch

Flexibility and Performance[edit]

  • Scalable in power output from 1 - 100 hp by scaling or adding modules
  • Power density of 1 hp/10 lb
  • Pressure up to 500 psi
  • Scalable cylinder dimensions, uncoupled staging, and tandem operation allows scaling of power and eficiency from 1-100 hp and up to 25% efficiency
    • Multiple cylinder, in-line configuration is possible by bolting several cylinders together

Performance-Chart.png

See the following for steam engine calculations:

Lifecycle[edit]

  • Long lifetime under continuous use (50 years)

Ecology[edit]


Sources[edit]


Parts List[edit]

The following list of parts is based on the initial set of technical drawings linked from Steam Engine Build Instructions.

Steam Engine Parts

  • Piston Assembly
    • Piston (1)
      • Piston Head (1)
      • Piston Stem (1)
      • Piston Stem Pin (1)
      • Piston Stem Pin Washer (1)
      • Piston Stem Pin Cotter (1)
    • Piston Rings (2)
    • Bump Valve Pins (2)
    • Connector Rod (1)
      • Coupler (1)
      • Rod (1)
      • Bearing Case Assembly (1)
        • Bearing Case Top (1)
        • Bearing Case Bottom (1)
        • Quarter Inch Bolts, 3/4" long (2)
        • Quarter Inch Nuts (2)
        • Quarter Inch Lock Whaters (2)
  • Cylinder Assembly
    • Cylinder Liner (1)
    • Cylinder Case (1)
      • Cylinder Pipe (1)
      • Cylinder Flanges (2) - Flanges are missing four bolt holes
    • Valve Seat Plate (1)
    • [Valve Seat Seal ???] - this is a thin, soft metal seal.
    • Cylinder End Mount (1)
      • Plate (1)
      • Flange (1)
      • Half Inch Base Bolts, 1" long (3)
    • Exhaust Plenum
      • Exhaust Plenum Elements (4)
      • Quarter Inch Plenum Bolts, 1.5" long (4)
      • Quarter Inch Plenum Lock Washers (4)
      • Quarter Inch Plenum Nuts (4)
    • Half Inch Cylinder End Bolts (8) - Bolts can be replaced by a threaded rod.
    • Half Inch Cylinder End Lock Washers (8)
    • Half Inch Cylinder End Nuts (8)
  • Valve Assembly
    • Valves (2)
    • Valve Springs (2)
    • Vavle Spring Base (2)
    • Valve Cover (1) - Cover could be extended to eliminate the mounting bracket
      • Valve Holder (1)
      • Valve Cover Plate (1)
      • Valve Cover Flanges (4)
    • [Valve Cover Seal ???] - this is a thin, soft metal seal.
    • Cylinder Mounting Bracket - has two base plate holes, but cylinder end mount has 3.
      • Upright Plate (1)
      • Flange (1)
      • Half Inch Base Bolts (2?)
    • Half Inch Valve End Bolts (8) - Bolts can be replaced by a threaded rod.
    • Half Inch Valve End Lock Washers (8)
    • Half Inch Valve End Nuts (8)
  • Other
    • Base Plate (1)
    • Oil Dribbler - TBD (1)


Crankshaft Parts

  • Shaft
    • Flywheel Shaft (1)
    • Drive Shaft (1)
  • Crank Assembly (1)
    • Crank Pin (1)
    • Crank Counterweight (2)
    • Crank Arm (2)
    • Nylon Bushings, 0.5" long (2)
  • Pillow Block Assembly (2)
    • Pillow Block Bearings (2)
    • Supoprt Element (1 - 2 total)
    • Support Base (1 - 2 total)
    • Support Rods (2 - 4 total)
    • Half Inch Pillow Block Bolts, 2" long (2 - 4 total)
    • Half Inch Pillow Block Lock Washers (2 - 4 total)
    • Half Inch Pillow Block Nuts (2 - 4 total)
    • Half Inch Base Bolts (2 - 4 total)
  • Flywheel Assembly (1)
    • Flywheel (1)
    • Collar (1)
    • Quarter Inch Set Screws, 0.5" long (2)

Techniques

  • Stock parts wherever feasible
  • Lathing for valves and other parts
  • Milling of exhaust plenum and other parts
  • Hole drilling
  • Cylinder boring may be necessary, depending on stock availability
  • Welding of parts in several places

Specification Decisions[edit]

There are a few key dimensions that need to be specified before the full dimensions of the engine and it's parts are known. These include:

  • Valve Gap - the amount of space open in the valves at top dead center.
    • Initially, we shall use 1/8" (0.125"). This can be adjusted by changing the valve pin length.
  • I.D. of a half inch bolt - needed to determine valve spring holes and valve stem diameter.
    • O.D. is 0.515", I.D. is 0.482". However, this might not be the size of the hole we need. See valve spring size.
  • Cylinder clearance - space remaining in the bore at top dead center.
    • "Steam Engines" recommends 3-8% of the piston displacement, which is 4". If we assume 6%, this is a clearance of 0.24, which we can round off to 0.25 (1/4 inch).
  • Exhaust port locations - near bottom dead center
    • We will use 3.6" from T.D.C as the left edge of the exhaust holes, which shall be 0.25" in diameter..