GB1262320A - Pipeline by-pass flow control system and method - Google Patents

Abstract

1,262,320. By-pass system for cleaning pipes in pipe-line systems. M. H. GROVE, and J. M. E. GROVE, [trading as M. & J. DEVELOPMENT CO.]. 25 March, 1969 [8 April, 1968], No. 15503/69. Heading F2N. In a booster station arrangement in a pipeline system for handling liquids such as petroleum products and which is adapted to allow cleaning spheres to by-pass a main station pump 11, the latter is connected by suction and discharge lines L 1 , L 4 respectively to flow-tees T1, T4 at the up and down stream ends of a by-passed line section 10 of a main line 10a, and, in addition, by suction and discharge lines L 3 , L 2 connected respectively with intermediate flow-tees T3, T2, the lines L 1 -L 4 incorporating valves V1-V4 respectively which are manually, or power, operated preferably by remote control, and which are preferably of the gate type provided with piston and cylinder hydraulic motors H1-H4 controlled respectively with electrical switch devices S1-S4. Devices D-1, D-2, D-3 for detecting the presence of cleaning and separating spheres are located respectively at the inlet, intermediate, and outlet positions of the by-pass 10 which also includes first and second check valves 16, 17, each of which allows the spheres to pass while preventing back-flow of fluid, the detecting devices D1-D3 being connected to a sequence controller 19 which initiates operations for the sequential opening and closing of certain of the valves V1-V4 according to the electrical pulses received from the detectors D-1, D-2 and D-3. The flow-tees T1 and T4 are provided with barriers which prevent a sphere from passing into the respective branch line L 1 or L 4 . A control panel 14, the details of which are described with reference to Fig. 7 (not shown), includes, for each hydraulic motor (H1), a four-way valve (26) which is controlled by solenoid valves (36, 37) and is regulated by the sequence controller (19) or manually. The flow path within each flow tee is inclined downwardly toward its outlet end so that a sphere, entering a tee, is induced by gravity, to proceed to the outlet end of the tee and not obstruct the opening leading to the associated branch line, Figs. 7 and 8 (not shown). In operation, assuming that the system is operating normally with the valves V1, V4 open and valves V2, V3 closed so that all of the fluid in the main line 10a is diverted along the branch line L 1 to the pump 11, which discharges the fluid back to the main line 10b through branch line L 4 , upon arrival of a sphere at the detector D-1, the opening and closing of the valves V3, V1 respectively takes place automatically, the sphere being sucked by the flow of fluid in the branch line 10 past the detector D-2 and up to the tee T3. The detector D-2 then initiates the opening of valve V1, the valve V3 starting to close when the valve V1 is fully open and the valve V2 opening when the valve V3 is closed. When the valve V2 is fully open the closing of the valve V4 is initiated. The fluid flow through the by-pass causes continued movement of the sphere in the by-pass 10 up to the detector D-3 which then restores the system back to normal. Fig. 6 (not shown), illustrates a suitable sequence controller with ports electrically associated to carry out a sequence of operations as described above. The controller includes mechanism which prevents the system operating should a second sphere arrive at the detector D-1 while a preceding sphere is passing along the by-pass 10. Means are also provided which disables the entire system in event of power failure to the main pump 11. In a modification, Figs. 9-11 (not shown), which is more simplified and employs only two detectors (D11) and (D12), valves (V11, V12) are normally closed with valves V13, V14 normally open so that flow normally takes place up to the tee (T13) and past the detector (D11) in the by-pass (10) to the suction side of the pump (11) which discharges through the valve (V4) to the detector (D12). As the sphere passes the detector (D11) the valve (V11) starts to open which action prevents any further spheres arriving passing through the flow tee (T11) and into the by-pass (10). When the valve (V11) is open, valve (V13) commences to close, and when the latter is completely closed valve (V12) commences to open, whereupon the valve (V14) starts to close. When the sphere passes the detector (D12), the system is restored to normal where valves (V11, V12) are open and valves (V13, V14) are closed.