CN2442261Y - Anti-leakage property test instrument for water-proof coiled material - Google Patents

Abstract

The utility model relates to a leakage resistance testing instrument for waterproof coiled material. An existing testing instrument has the defects of complicated structure, complicated operation, and large testing error. The testing instrument of the utility model utilizes a sealing piston to make the volume of liquid in a cylindrical sealed cavity compressed to certain pressure, and the relationship of the pressure of a pressure meter and the time is recorded to calculate the leakage amount of water to obtain the leakage resistant performance of tested samples. The leakage resistance testing instrument has the advantages of simple structure, low cost, convenient operation, and high accuracy.

Description

A kind of waterproof roll anti-permeability performance tester

The utility model is a kind of instrument that is used for the test of waterproof roll anti-permeability performance.

The domestic existing standard GB/T17642-1998 of the test of waterproof roll anti-permeability performance, Ministry of Water Resources has also issued ministerial level standard SL/T235-1999, and external no this item standard still, do not improve ripe detection method and instrument but still have at present, its crucial part is to record seepage flow (seeing " geotextile and relevant product prostatitis national standard a surname thereof are passed through teaching material ") more accurately.The Anti-leakage instrument of Nanjing Shui Keyuan (seeing SL/T235-1999 " geotextile and relevant product test handbook thereof "), it uses air compressor machine as pressurized equipment, measuring the seepage flow pipe is small one and large one two buret, this kind instrument is because the influence of factors such as pipeline, very high to the operation requirement, and be easy to cause personal error.

The purpose of this utility model is the waterproof roll anti-permeability performance tester that a kind of simple structure of design, easy to operate, precision improve.

Anti-leakage instrument of the present utility model is made up of annular seal space, piston, base, holding ring and tensimeter.The annular seal space upper and lower opening of column type is equipped with packed-piston above and is used for pressurization, seals with holding ring clamping sample with base below, and water is housed in it.Annular seal space tube wall end outwards has chimb, and also there is protrusion base and annular seal space tube wall corresponding position.The matrix holding ring is with the raised seals clamping of two places, and flat being clipped in wherein of testing sample tested.Because this characteristic that concerns of the volume change that the utility model utilizes water and pressure variation, therefore tested media is a water, come the impermeability of specimen by testing sample with pressure (hydraulic) water, therefore on the base infiltration structure must be arranged, being embedded with a microwell plate in the middle of the utility model base, is hollow in the middle of the base, and microwell plate partly seat is fixed in base, the middle base intermediate hollow part that partly sees through can directly outwards seep water.For detecting hydraulic pressure, the high-precision pressure table is housed in annular seal space tube wall bottom.

Microwell plate on this instrument base can be to make of permeable stone, and cost is low, and material is easy to get.

Pressurization piston of the present utility model can be used the electrodynamic type piston when water in annular seal space pressurizes, test operation not only simply but also accurate like this.

Measuring instrument of the present utility model can be used for the test of waterproof roll anti-permeability performance, is mainly used in the anti-permeability performance test of composite geo-membrane.

This instrument compressed liquid can be tested, and pressure-producing part can realize that promptly screw fixed between annular seal space and pressurizing piston is backed out spiral promotion packed-piston and made liquid compression during pressurization with the screw press piston.

Use the utility model instrument, test process is as follows:

The impervious coefficient of I

1 installs sample, has added degassing pure water;

2 motion packed-pistons are forced into required pressure, and whether (than the big 0.01MPa in test pressure side) optical viewer has the infiltration situation, if do not have, shows in order;

Pressure and time between 3 record P+0.01～P-0.01, paint P～t curve, rate of curve (dP/dt) is the pressure fall off rate during pressure power P;

4 dry instrument moisture content on every side, pour out water in the container, obtain volume V with graduated cylinder or additive method;

5 calculate impervious coefficient according to hydraulic formula and impervious coefficient k computing formula $\mathrm{\βp}=\frac{\mathrm{dV}/V}{\mathrm{dp}}\⇒\mathrm{dV}=-{\mathrm{\β}}_P\·\mathrm{dp}\·V$ K=QT/ (tA Δ p) Q-water percolating capacity; T-seeps water the time; T: thickness; A: area; P: pressure reduction; β _P: the coefficient of volume compressibility of water, get 4.85 * 10 for 20 ℃ ^-10m ²/ N, the coefficient of volume compressibility of other temperature can be tabled look-up and be obtained; Q/t gets with the dV/dt replacement $k=\frac{\mathrm{dV}}{\mathrm{dt}}\·\frac{T}{A\·P},$ Then can get $k=\frac{{\mathrm{\β}}_P\·\mathrm{dP}\·V}{\mathrm{dt}}\·\frac{T}{A\·P}$ $k={\mathrm{\β}}_P\·\frac{\mathrm{dP}}{\mathrm{dt}}\·\frac{V\·T}{A\·P}$ DP/dt: can check in MPa/s from curve; V: graduated cylinder measures, annular seal space inner volume, cm ³(after the off-test, 10ml); A: effective seepage area, cm ², be fixed value; T: geomembrane thickness cm, thicknessmeter records; P: pressure reduction cm (available 1kPa=10cm water column conversion) stipulates certain pressure differential P; Like this, infiltration coefficient is easy to obtain, and its precision meets in GB and the Ministry of Water Resources's examination criteria fully to be stipulated.II resistance to hydrostatic pressure value 1. clips geomembrane, makes hydraulic pressuring difference reach 0.1MPa, as estimating the general range of sample resistance to hydrostatic pressure, can directly hydraulic pressuring difference be added to this scope lower limit; 2. observed 2 hours, and quick decline do not occur as pressure in the tensimeter, (even descend 0.05MPa in 2 hours, also not very broken, be normal seepage flow); 3. be differential pressure boost gradually with 0.1～0.2MPa, every grade all kept 2 hours, descend fast until pressure, and as seen the geomembrane downside had water, shows then to be punctured by hydraulic pressure that the value of getting its previous stage is as the resistance to hydrostatic pressure value; 4. triplicate is got minimum value as the resistance to hydrostatic pressure value.

At clamping composite geo-membrane position placement force table, water percolating capacity is calculated in decline according to force value.Pressuring method is then abandoned air compressor machine, directly utilizes the effect of packed-piston on the de aerated water of sealing, makes the water body compression and raising pressure.The method of this measurement seepage flow can improve measuring accuracy greatly.Its precision is directly proportional with the tensimeter precision, is the tensimeter of 0.005MPa as common precision, and its water percolating capacity precision then can reach 2.5 * 10 ^-3Ml is 4 times of precision 0.01ml of prior art; Such pressuring method is easy, does not need other pressurized equipments such as air compressor machine, has saved manufacturing cost.Therefore the utility model apparatus structure is simple, and test operation is convenient, and measuring accuracy improves, and provides economical and practical surveying instrument for improving canonical measure.

Fig. 1 is the cut-away view of the utility model tester.Wherein 1 is the column type annular seal space, the 2nd, and packed-piston, the 3rd, tube wall is terminal to be protruded, and the 4th, base, the 5th, base protrudes, and the 6th, holding ring, the 7th, permeable stone, the 8th, tensimeter, the 9th, pressurizing piston, the 10th, sample to be tested.

Embodiment:

Get an interior diameter 59cm, the stainless pipe of high 28cm is made the column type annular seal space of upper and lower opening, and the nearly base position of tube wall is installed a high precision digital display manometer, and the tube wall end is the type of pulling out that pushes away along the wall evagination.Base is made with same material, and base diameter is identical with annular seal space, also pushes away in its outer ring and capsule walls corresponding position to pull out shape and protrude, two protruding places need use the clamping of matrix holding ring, embed a permeable stone in the base, hollow out in the middle of the base makes permeable stone expose to the space at the hollow out place.

Get the circular steel plate of the thick 5cm of a diameter 59cm, the side y-shaped ring that stretches tight can constitute a simple packed-piston, can certainly buy the packed-piston of finished product.Weld the stainless steel force-transmitting pole of the long 5cm of a diameter 20cm at circular steel plate upper surface.

At the screw thread of pipe upper inner car 5cm pitch 1mm, the screw thread of the long 10cm stainless steel bar of cut-off footpath 59cm surface car 5cm pitch 1mm is supporting with pipe in addition.The downward driving of stainless steel bar can down be twisted with hand, can be at car one duck eye in the middle of the stainless steel bar, and force-transmitting pole passes from the hole and places under the pressing machine, when waiting to be depressed into required pressure, with bolt packed-piston is fixed,, preferably joined a miniature motor and make it to drive for easy to operate simple.

Claims (5)

1. waterproof roll anti-permeability performance tester, by the cylindrical seal chamber, piston, base, holding ring and tensimeter are formed, it is characterized in that column type annular seal space (1), be the packed-piston (2) that can pressurize above, its bottom is an opening, the tube wall end outwards protrudes (3) along tube wall, base (4) is to protrude (5) with annular seal space tube wall corresponding position, matrix holding ring (6) is with the raised seals clamping of two places, be embedded with the microwell plate (7) identical in the middle of the base with the annular seal space interior diameter, the base intermediate hollow, microwell plate part seat is in base, middle part communicates with the external world, and tensimeter (8) is arranged at the tube wall bottom.

2. waterproof roll anti-permeability performance tester according to claim 1 is characterized in that the microwell plate on the tester base is a permeable stone.

3. waterproof roll anti-permeability performance tester according to claim 1 is characterized in that the packed-piston that can pressurize on the column type annular seal space is the electrodynamic type piston.

4. waterproof roll anti-permeability performance tester according to claim 1 is characterized in that this tester is mainly used in the anti-permeability performance test of composite geo-membrane.

5. waterproof roll anti-permeability performance tester according to claim 1 is characterized in that pressure-producing part is the screw press piston on the tester packed-piston.