An example use case for the present invention is in the field of high-pressure hydraulic fracturing (aka: “fracing”), as used in the oil production industry. Fracing includes the use of high-pressure, positive displacement, pulsing pumps to deliver suspended sand fracing fluids to subsurface areas containing oil deposits. The fracing process cracks the formation where oil resides and places sand in the fractures for improved oil flow and volume to the wellbore.
Although utilizing the fracing process increases the cost of production for a well using it, the process can substantially increase the efficiency of the well's production. In times of high oil prices, the increase of production efficiency exceeds the cost of the fracing process. Demand for fracing, along with horizontal drilling spurred a boom in US oil and natural gas production. However, in times of low oil prices, the increase in production efficiency does not offset the cost of the fracing process for the well, and low producing wells are shut-in, rather than initiating a fracing operation. Even the largest hydraulic fracturing operations in the US have been forced to dramatically cut costs in response to reduced demand for services. With oil companies cutting and expecting to continue to cut more than 100 billion dollars in spending globally, fracing expenditures are expected to concomitantly fall as much as 35%. It has been reported that about half of the hydraulic fracturing companies operating in the US would be closed or sold by year-end 2015, because of falling oil prices and reduced oil company expenditure.
With a continuing poor outlook for a significant increase in oil prices in near and mid-term future, solutions for reducing production expenses, including fracing costs, are expected to be a continued critical focus. One critically high cost common in the fracing industry is related to equipment failures, caused by the high-pressure, pulsating flow into the fracing piping. The high-pressure, pulsating flow results from the massive positive displacement pumps used to pump the fracing fluids into the fracing piping. The pressure pulses slam the couplings, joints and fittings of the piping with thousands of pounds of force three hundred (300) times per minute causing failure of these fittings. Replacement of high-pressure fracing equipment is very expensive. Failed fracing fixtures and pipe also results in costly downtime required to resource and replace failed components before the production process can continue. Pumps, piping, fittings, and valves are all adversely affected by the very high-pressure pulses from the massive positive displacement fracing pump systems. The industry has long been in search of meaningful solutions to the fracing iron failure problem. It would be seriously beneficial to the oil production industry, and hydraulic fracturing services specifically, if a means for reducing fracing costs could finally be provided with a solution.
However, there are serious barriers to safe and successful implementation pulsation dampening on high-pressure pulsatile flow lines. One major barrier is to the use of “gas-cushioning” in pulsation dampeners. This is because in high-pressure applications (e.g., pressures on the order of 20,000 psig), the very highly compressed gas can present a very real explosion threat and potential injury to nearby persons and equipment. Another barrier that has long prevented the application of “gas-cushioning” in pulsation dampeners is the limitations of gas-seals in the dampener apparatus to withstand and be proof against the high Δp (pressure differentials) typical of high-pressure pulsatile flow systems. Also, in “gas-cushioning” type pulsation dampeners with moving interfaces (e.g., a sliding piston) the pressure differentials across barriers (e.g., walls) separating liquid and gaseous spaces can be distorted or caused to balloon under the pressure differences. This is a serious problem for maintaining liquid/gas seal integrity at a dampener's moving/sliding interfaces.
Reference Numerals DDepth of the interior wall LLength of Dampener housing 10HP flow pulsation dampener 12Dampener housing 14Dampener housing end 14aDampener housing 1st end 14bDampener housing 2nd end 15Dampener housing axis 16High-pressure fluid flow line 17Fluid I/O port 17aFluid inlet port 17bFluid outlet port 20Housing-to-flow line adapter 22Fluid flow thru-path 24Non-flow fluid chamber 26Liquid communication means 28Dampener housing fluid space 30Union 33Union flange member 34 Union flange member(a&b) 36Flange fasteners 50Damper canister 52Canister housing 53Canister housing axis 54Canister interior space 55Canister flange 56Canister opening 57Canister rim 58Canister interior wall 59Canister interior bulkhead 60Piston stop ring 61Fastener aperture 62Stop ring fasteners 64Through-flow spacer ring 66Radius stand-off 68Ring fluid port 69Canister piston stop shoulder 70Damper piston assembly 72Damper piston 74Damper piston head 75aPiston gas pressure surface 75bPiston fluid pressure surface 76Damper piston skirt 79Piston ring channel 82Wiper ring 90Gas port fitting 92Gas port 94Gas valve 96Gas port cover102Canister gas port
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