CN2059499U

CN2059499U - Tester for uplift pressure of reservoir dam

Info

Publication number: CN2059499U
Application number: CN 89205466
Authority: CN
Inventors: 李载达; 徐毓澄
Original assignee: NANJING AUTOMATION INST
Current assignee: NANJING AUTOMATION INST
Priority date: 1989-10-26
Filing date: 1989-10-26
Publication date: 1990-07-18

Abstract

The utility model relates to a tester for uplift pressure of reservoir dam, which is composed of a water depth sensor, and a weight dropper, wherein, the output end of the circuit of the water depth sensor is transmitted by a cable to an observation room for centralized detection by the output frequency signal of a V/f changeover circuit integrated package; the cavity of the water depth sensor is connected with an oil isolator to make the cavity seal by oil face, and can be in self-balance with outside atmospheric pressure. The utility model has the advantages of less equipment investment, convenient operation, and high precision, having high anti-interference ability for transmission in fields.

Description

Tester for uplift pressure of reservoir dam

The utility model is about a kind of depth of water pick-up unit, particularly about detecting the depth of water detecting device of reservoir dam uplift pressure.

Reservoir dam can produce the infiltration phenomenon because of quality problems, just may cause dam deformation, collapse if local infiltration surpasses certain limit, and this will cause great loss to the basin, downstream.In order to guarantee the safe operation of reservoir, generally having several at each position of dam when founding a capital the dam is liner with the steel pipe, and diameter is about the well logging of 10cm, so that regularly measure each well water position height value (being uplift pressure), in time scents a hidden danger, and keeps in repair.Traditional uplift pressure detection method is time-consuming taking a lot of work mostly, and the equipment rapid wear, and measuring error is also big.Developed a kind of depth of water sensor in recent years, change the principle of resistance according to silicon pressure drag pressurized, convert uplift pressure to d. c. voltage signal output,, thereby time saving and energy saving and solved the problem of camp equipment rapid wear by cable transmission to observation ward's centralized detecting.But observation ward and dam distance is bigger, and this sensor output signal a little less than, be the various interference of avoiding transmitting in the way, cable must be provided with expensive screen layer.In addition, because the pressure rh of water column in the well logging _iBe the reference pressure P in the sensor annular seal space _ORecord down, actual uplift pressure also must be carried out pressure correction, that is:

P=rh _i+ P _Atmosphere-P _O

P in the formula---uplift pressure

R---water proportion

h _i---the water column height

P _O---the reference pressure in the sensor cavity

Also must establish atmosphere pressure sensor for this reason in addition and measure P _AtmosphereValue, not only increased equipment investment, and influenced accuracy of detection.

In view of this, the purpose of this utility model provides a kind of easy to use, and equipment investment is few, measuring accuracy height, the reservoir dam uplift pressure detecting device of strong anti-interference performance.

The utility model uplift pressure detecting device is made up of depth of water sensor and weight, and to be threaded, weight (12) has inlet opening (11) between the two, and the upper end is embedded with permeable stone (10), and itself and inlet opening link; Depth of water sensor is made up of cavity (8), silicon cup (9) and wiring board, and silicon cup is fixed in the lower end of cavity, and wiring board places in the cavity, and by cable (13) output electric signal; Wiring board is by positive and negative stabilized voltage supply IC ₁, IC ₂With four-operational amplifier IC ₃And silicon pressure drag RC output bridge circuit composition loop, silicon pressure drag RC contacts with silicon cup (9).The utility model is at above-mentioned amplifier IC ₃Output terminal connect a V/f change-over circuit ic chip ₄, the output terminal of this integrated package successively with resistance R ₃₀And triode T ₁Base stage connect, and by triode T ₁Emitter connect with cable (13), be transferred to observation ward with frequency signal.For making the pressure in the sensor cavity consistent with external atmosphere pressure, the utility model is gone up at sensor cavity (8) and is connected an inverted U-shaped pipe (3), one end of this U-shaped pipe is connected with the oily isolator (6) that fluid (5) is housed, and pipe end stretches in the fluid, the sensor cavity is promptly sealed by fluid, the top of oil isolator (6) has air hole (4) and communicates with atmosphere, when atmospheric pressure changes, fluid promptly fluctuates between oily isolator and U-shaped pipe, thereby the sensor cavity internal pressure is changed thereupon synchronously, keep balance with external atmospheric pressure all the time.

This detecting device is fastened the galvanized wire of pulling strings (2), it is dropped in the well logging (1), owing to the effect of weight is sunk, by the control of pulling strings being made it rest on a certain position in the well, well water sees through permeable stone (10) by hole (11) and acts on silicon cup (9), makes the silicon pressure drag RC that places on the silicon cup be subjected to hydraulic pressure and produces change in resistance, and bridge circuit output also changes thereupon, amplify through amplifier, convert frequency signal to through the V/f change-over circuit again and export by cable.

Adopt the utility model detecting device to detect the uplift pressure at each position of dam, can make the height value of water column convert frequency signal output to, its with prior art in compare with voltage signal output, the interference free performance of signal strengthens, therefore, can adopt the common electrical cable transmission of unshielded layer, reduce investment cost.Owing to set up oily isolator, under the condition that sensor seals in guaranteeing the chamber can with the external atmosphere pressure self-equilibrating, both can prevent from that extraneous humid air from entering to damage element in the cavity, solved the problem of pressure correction again, make that to detect data accurate, and simplified equipment.In sum, the utility model is easy to use, strong anti-interference performance, and the measuring accuracy height, equipment investment is few, has reached the goal of the invention of aforementioned proposition.

Embodiment below in conjunction with description of drawings the utility model reservoir dam uplift pressure detecting device.

Fig. 1 is the structural representation of present embodiment uplift pressure detecting device.

Fig. 2 is the sensor circuit figure of present embodiment.

Present embodiment is from sensor outgoing cable line (13), steel wire (2) and U-shaped pipe (3), and the three protects with same plastic tube (7) sealing.When detecting uplift pressure, steel wire (2) upper end should be securely fixed in the well head place.The V/f change-over circuit adopts commercially available AD537 type integrated package in the present embodiment.

Claims

1, reservoir dam uplift pressure detecting device is made up of depth of water sensor and weight, and both are to be threaded, and the lower end of sensor cavity (8) is fixed with silicon cup (9), by positive and negative stabilized voltage supply IC ₁, IC ₂With four-operational amplifier IC ₃The wiring board that reaches silicon pressure drag Rc output bridge circuit composition loop places in the cavity (8), and silicon pressure drag Rc contacts with silicon cup (9), it is characterized in that described amplifier IC ₃Output terminal connect a V/f change-over circuit ic chip ₄, the output terminal of this integrated package successively with resistance R ₃₀And triode T ₁Base stage connect, and by triode T ₁Emitter connect with cable (13), export with frequency signal.

2, as the described reservoir dam uplift pressure of above-mentioned claim 1 detecting device, it is characterized in that, depth of water sensor cavity (8) is gone up and is connected an inverted U-shaped pipe (3), one end of this U-shaped pipe is connected with the oily isolator (6) that fluid (5) is housed, and pipe end stretches in the fluid, and the top of oily isolator (6) has air hole (4).