Propane regulator with a balanced valve

A propane or liquefied petroleum pressure regulator comprising:

• an inlet port configured for connection to a source of one of propane and liquefied petroleum to receive gas therefrom at a varying supply pressure;
• a supply valve and a supply seat in fluid communication with the inlet port for selectively passing gas from the inlet port to an outlet port, the supply valve having a first surface area that is acted upon by the gas at the inlet pressure to bias the supply valve toward the supply seat in accordance with the supply pressure and the first area and a second surface area that is acted upon through the supply seat by the gas at an outlet port pressure to bias the supply valve away from the supply seat in accordance with the outlet Port pressure and the second area;
• a pressure set point adjustment which biases the supply valve away from the supply seat with a biasing force set by an operator in accordance with a selected outlet port pressure;
• a first fluid pressure feedback passage for feeding back gas from the outlet port at the outlet port pressure to the pressure set point adjustment, the fed back outlet port pressure counteracting the force set by the operator to bias the supply valve toward the supply seat in accordance with the fed back outlet port pressure;
• a balance element having a first surface with a first area and a second, opposite surface with a second area, the balance element first surface area being substantially the same as the supply valve first surface area and the balance element second surface area being substantially the same as the supply valve second surface area, the balance element first surface being in fluid communication with the inlet port such that the balance element first surface is acted upon by the supply pressure;
• a second fluid pressure feed back passage for feeding back gas from the outlet port at the outlet port pressure to the balance element second surface such that the fed back outlet pressure acts on the balance element second surface;
• a mechanical connection between the balance element and the supply valve such that the supply valve is biased away from the supply seat in accordance with the supply pressure and the first surface area and is biased toward the supply seat in accordance with the fed back outlet port pressure and the second surface area;
• and
• an annular sliding frictional damping element connected to the balance element for damping movement of the balance element in response to supply and outlet port pressure changes to limit a speed with which the supply valve moves relative to the supply seat in response to the supply and outlet port pressure changes as well as turbulent flow effects on the supply valve, the balance element and the mechanical connection.

A pressure regulator for propane and liquefied petroleum comprising:

• an inlet port, said inlet port receiving supply pressure;
• an outlet port, said outlet port receiving output pressure;
• a pressure set point adjustment including:
• a T-handle adjustment including a rotatable T-handle and a threaded shaft;
• a spring assembly, said threaded shaft engages said spring assembly;
• a diaphragm assembly, said diaphragm assembly engages said spring assembly;
• said T-handle is rotated to move said spring assembly downward, compressing said spring, and creating a net downward force on said diaphragm;
• a valve mechanism including:
• a supply seat located between said inlet port and said outlet port;
• a supply valve which engages said supply seat;
• a balance piston which is positioned below said supply valve;
• a pintle interconnection, said pintle interconnection threads to and connects said supply valve and said balance piston to said diaphragm assembly, said supply valve moves off of said supply seat as said downward force is exerted on said diaphragm assembly, supply pressure fills said outlet port as said supply valve moves off of said supply seat;
• a balanced valve including:
• a balanced diaphragm, said balanced diaphragm located on a top surface of said balance piston and below said supply valve, and
• an o-ring, said o-ring is positioned within said balance piston;
• and,
• an aspirator tube, said aspirator tube transfers supply pressure from said outlet port to said diaphragm resulting in a net upward force on said diaphragm as a function of outlet pressure times diaphragm area.

A method for regulating pressure for propane and liquefied petroleum comprising:

• (a) feeding propane or liquefied petroleum gas as a supply pressure to a valve and a seat, such that the gas acts on a lower surface of the valve to bias the valve toward the seat with a first force:
• (b) mechanically creating a downward second force on a first movable seal, said second force is equal and opposite to the first force;
• (c) moving the valve off the seat in response to the second force and against the first force allowing the gas to flow between the valve and the seat to create an output gas pressure downstream of the seat, which output gas pressure acts through the seat to bias the valve away from the seat with a third force;
• (d) operating on a second movable seal that is connected to the valve with the gas at the supply pressure to bias the second movable seal and the valve with a fourth force, which fourth force is equal and opposite to the first force;
• (e) feeding back the gas at the output pressure to the first seal to create an upward fifth force on the first movable seal;
• (f) feeding back the gas as the output pressure to the second seal to bias the second movable seal and the valve with a sixth force which sixth force is equal and opposite to the third force;
• (g) moving the valve relative to the seat until the second and fifth forces counter balance;
• (h) concurrently redundantly sealing the valve and using sliding frictional drag to damp movement of the valve to limit a speed at which the valve moves relative to the seat.