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   Pump Jack Hydraulic Cylinder Engines 

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  Pump Jack Hydraulic Cylinder Engines 
 These engines derive their power from the extension and retraction of hydraulic cylinders. The pressure to operate the cyclinders is created by heating propane is hot water and then pressurizing a tank filled hydraulic fluid using the pressurized gas.

 This engine uses a pivot beam with some cable and a hydraulic cylinder to provide the lift in and out of the water for the gas tank and drive a output shaft. The gas pressurizes a tank with hydraulic fluid which operate the hydraulic cylinder.   The cylinder in this setup is a log splitter type with a 4″ diameter piston and a 24″ extension.   The output is 2 powered rotations per cycle at about 300 ft lbs torque then 2 low power rotations as the beam and cylinder reset.

  This engine also uses a hydraulic cylinder to provide the movement force. In this version The cylinder lifts itself , the hydraulic fluid tank, the gas tank, inner frame and turns the output shafts using wind one/off cable drums.  The output shafts turn in opposite directions when operating.  The output is roughly the same as the beam engine system above.  This design is easy to scale up of down as needed.  The only real requirement is that the gas tank gets completely removed from the water bath when the hydraulic cylinder is completely extended.  The gas tank should have at least a couple of inches of clearence above the water tank at the end of the extension stroke.  A mechanical release system like the one incorporated in the cable engines in the section above can also be added if wanted.

Both of these engines above can put out much more power than I’m designing them to use. By limiting the output of the cylinder to about 1000 lbs the frames of the systems don’t have to be that big.  The systems are both easily capable of putting out over 2000 lbs depending on the hot water temperature. I prefer to keep the gas pressure below 125 psi.  Propane tanks are actually capable of holding over 300 psi. The relief valves are generally set about 325 psi.
  300 psi would be an output of over 3700 lbs of force. It would need a much stronger frame to withstand that type of power.

This version operates a slightly differently than most of the types I have been designing. It uses two 4″ by 24″ hydraulic log splitting cylinders to make the output through a winding drum like some of the other designs.  The output is geared up though chains and sprocket gears. This design is completely mechanical in operation.

  What is different is it uses a propane flash boiler to generate the pressure for the cylinder. After the cylinder is extended the propane gas is vented off into a condenser system that stores it as liquid until needed for the next cycle.

 The picture shows the system in two parts because one fits behind or in front of the other. It doesn’t matter which way it is arranged.  

  Each cylinder has it’s own flash boiler and condensing system.  The two systems are operated by the position of the cylinder extension rods.  There is a simply a slide type link that controls both sides at the same time like that used on some steam engines.

  The exhaust valves and the feed pumps are all operated by magnetic repulsion. This allows the system to maintain  complete integrity in the propane loops to prevent any possible leaks from valve stems or piston rods. 

 The system pumps it’s own cooling and heating water through two separate double acting piston pumps.   The pumps pump slightly more cooling water than hot water.   The cooling water should be supplied by a large tanks or cooling coils.   The hot water can be supplied by a back of solar hot water panels or some other heating source such as a coil heated by some sort of wood burning stove.   Any source of hot water will work but should be capable of at least 3 gallons per stroke of the cylinders.

 The cylinders are tied together hydraulically also so at least one side of both cylinders will provide power during a cycle.  This is not shown in the picture, nor are the feed hoses to the cylinders or hot and cold water plumbing for simplicity.  The locations where they would go are marked of ease of understanding. 

This system is capable of up to 16 hp theoretical maximum output using 250 psi gas pressures and 4 cycles per minute.  100 psi with 2 cycles per minute would give a working output of about 2.5 hp.  This should be easy to attain.