CN209945934U - Simple device for measuring apparent density of light aggregate powder - Google Patents
Simple device for measuring apparent density of light aggregate powder Download PDFInfo
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- CN209945934U CN209945934U CN201920348803.4U CN201920348803U CN209945934U CN 209945934 U CN209945934 U CN 209945934U CN 201920348803 U CN201920348803 U CN 201920348803U CN 209945934 U CN209945934 U CN 209945934U
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- cantilever
- beaker
- apparent density
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- support column
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- 239000000843 powder Substances 0.000 title claims abstract description 38
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 35
- 239000012528 membrane Substances 0.000 claims abstract description 25
- 238000007789 sealing Methods 0.000 claims abstract description 23
- 238000000108 ultra-filtration Methods 0.000 claims abstract description 22
- 238000004321 preservation Methods 0.000 claims abstract description 3
- 238000003825 pressing Methods 0.000 claims description 24
- 230000002209 hydrophobic effect Effects 0.000 claims description 6
- 239000002184 metal Substances 0.000 claims description 6
- 229910052751 metal Inorganic materials 0.000 claims description 6
- 239000004033 plastic Substances 0.000 claims description 3
- 229920003023 plastic Polymers 0.000 claims description 3
- 239000002245 particle Substances 0.000 abstract description 7
- 238000000034 method Methods 0.000 description 14
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- PEDCQBHIVMGVHV-UHFFFAOYSA-N Glycerine Chemical compound OCC(O)CO PEDCQBHIVMGVHV-UHFFFAOYSA-N 0.000 description 3
- 238000001739 density measurement Methods 0.000 description 3
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- 238000004519 manufacturing process Methods 0.000 description 2
- 239000004005 microsphere Substances 0.000 description 2
- -1 polypropylene Polymers 0.000 description 2
- 229920001155 polypropylene Polymers 0.000 description 2
- 239000004576 sand Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
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- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
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- 238000003889 chemical engineering Methods 0.000 description 1
- 239000000084 colloidal system Substances 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000005292 diamagnetic effect Effects 0.000 description 1
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- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
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- Separation Using Semi-Permeable Membranes (AREA)
Abstract
The utility model provides a measure simple and convenient device of light aggregate powder apparent density, seal bag, beaker and constant temperature basin including horizontal base, support column, cantilever anchor clamps, push down scale post, milipore filter, on the support column vertical fixation was on the horizontal base, cantilever anchor clamps height-adjustable's vertical fixation was on the support column, pushed down scale post and support column parallel arrangement, its upper end and cantilever anchor clamps are connected, milipore filter seal bag hangs in the lower extreme that pushes down the scale post. The beaker is filled with water with a known volume, the beaker is placed on a horizontal base and is positioned right below an ultrafiltration membrane sealing bag which is correspondingly packaged with a powder sample, and a cantilever clamp is adjusted to descend, so that the whole device is placed in a constant-temperature water tank for heat preservation after the ultrafiltration membrane sealing bag is immersed in the beaker. The device has simple structure and wide practicability, and provides a solution for demanders lacking a special powder particle density measuring device. When in application, the required data are measured and recorded: and then density calculation is carried out according to a corresponding formula, and the obtained result has high accuracy.
Description
Technical Field
The utility model belongs to the technical field of the density measurement, concretely relates to measure simple and convenient device of light aggregate powder apparent density.
Background
The density of materials is almost always known and measured in civil engineering, metallurgy, chemical engineering, scientific research and production of materials, because the measurement of density is an important part of controlling engineering and product quality. Most solid materials contain more or less porosity and voids. Thus, there are four different defined densities for the solid material: density (absolute density), apparent density, bulk density, and bulk density. Apparent density refers to the ratio of mass to volume in the natural state. The volume of a material in its natural state includes the volume of closed pores contained in the material, i.e., the apparent or apparent volume of the material. For a closed block material with a regular geometric shape, the geometric dimension can be directly measured, and the apparent volume can be calculated; for solid materials of irregular shape or having open porosity, the apparent volume is typically measured by the tapping method. For bulk solid materials with a density less than water, drainage measurements can still be made by either the colligation immersion method or the acupressure method. For most solid powder particles, measurements are often made using volumetric flasks or a lees pycnometer. However, for light aggregate powders having a density less than that of water or even kerosene, the above method is no longer applicable due to its dispersibility and evasion property.
At present, the measurement method aiming at the light aggregate powder with the density lower than that of kerosene is very rare, and the application of the light aggregate powder is limited to a certain extent.
CN103743651A discloses a device for measuring the average density of minute masses, which can accurately measure the average density of minute masses by non-contact force of irregular minute masses on a stage in liquid. However, since the permanent magnet and the ammeter are used as the stress measuring device, only the average density of the non-or weakly magnetic micro-particles can be measured, and the powder containing magnetic minerals and the apparent density cannot be measured.
CN205562331U discloses a substance density measuring device, which utilizes a gas specific heat ratio determinator to measure the density. But the air pump, the sealing rubber ring and the assembled flask have strict requirements on air tightness, so that the actual operation process is complicated and fussy.
CN107478543A discloses a centrifugal density measuring device and method based on the diamagnetic suspension principle, which realizes the material density measurement through the suspension height measurement. However, due to the large size and high price of the magnetic field generating device, the measuring box, the rotating device and the image acquisition control device, the device is not specially equipped and applied in production fields and laboratories.
And no simple device and method for measuring the apparent density of the lightweight aggregate powder exist at present.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to provide a can accurate simple and convenient device and application method of measuring light aggregate powder apparent density.
The utility model provides a simple and convenient device for measuring apparent density of light aggregate powder, which comprises a horizontal base, a support column, a cantilever clamp, a downward pressing scale column, an ultrafiltration membrane sealing bag, a beaker and a constant temperature water tank, wherein the support column is vertically fixed on the horizontal base; the beaker is filled with water with a known volume, the beaker is placed under an ultrafiltration membrane sealing bag correspondingly packaged with a powder sample on a horizontal base, and a cantilever clamp is adjusted to descend, so that the whole device is placed in a constant-temperature water tank for heat preservation after a scale column is pressed downwards to press the ultrafiltration membrane sealing bag into the water in the beaker.
In an embodiment of the above technical scheme, the cantilever fixture includes a cantilever, a fixture and a vertical connecting member, the fixture includes a buckle and two fastening knobs, the buckle has a supporting column clamping groove and a cantilever clamping groove, and the two fastening knobs are respectively connected to the side walls of the two clamping grooves.
In an embodiment of the above technical scheme, the horizontal base is a rectangular base made of metal, the support column and the cantilever are cylinders made of metal, and the downward pressing scale column is a cylinder made of PVC hydrophobic plastic.
In one embodiment of the above technical scheme, one end of the cantilever is an external thread head, the upper end of the downward pressing scale column is the external thread head, and the lower end of the downward pressing scale column is provided with a fixing ring.
In one embodiment of the above technical solution, the range of the pressing scale column is 10-50ml, the minimum scale is 0.1ml, and the scale compensates and corrects the volume of the fixing ring.
In an embodiment of the above technical scheme, the vertical connecting piece includes the protruding platform of cylinder and its side arm, and the lower extreme of cylinder has vertical internal thread hole, has horizontal internal thread hole on the protruding platform, the one end of cantilever is fixed in horizontal internal thread hole through the connection of external screw thread head, the upper end of pushing down the scale post is fixed in vertical internal thread hole through the connection of external screw thread head.
In one embodiment of the above technical scheme, the ultrafiltration membrane sealing bag comprises a bag body and an airtight seal at the upper end of the bag body, wherein a lifting rope is fixed on the bag body and bound on the fixing ring through the lifting rope.
The utility model discloses an adopt the milipore filter to seal the bag and encapsulate the powder sample, retrained the chaotic dispersion and the escape of powder sample. The scale post will be pressed down and the one end of cantilever anchor clamps is fixed in, and the milipore filter seals the bag and is fixed in the lower extreme that pushes down the scale post, when adjusting cantilever anchor clamps and descend along the support column, pushes down the scale post and descends thereupon, can realize that the milipore filter seals the aquatic of sand bag and powder sample submergence in the beaker completely, avoids the immersion process to bring the bubble into, stops that small particle escapes to the surface of water, pushes down the scale post and withholds the milipore filter and seal the bag, guarantees apparent density measuring result's accuracy nature. The device has simple configuration, convenient material taking and low investment cost, but can ensure the accuracy of the measuring result. The utility model discloses extensive applicability does not have the requirement to whether powder particle has magnetism. For hydrophilic and easily soluble powder particles, kerosene or glycerol with hydrophobic property in an aqueous solution can be flexibly replaced.
Drawings
FIG. 1 is a schematic structural diagram of an embodiment of the present invention
Fig. 2 is an enlarged top view of the cantilever clamp of fig. 1.
Detailed Description
As shown in fig. 1 and fig. 2, the simple and convenient device for measuring the apparent density of the lightweight aggregate powder disclosed in this embodiment includes a horizontal base 1, a support column 2, a cantilever clamp 3, a downward-pressing scale column 4, an ultrafiltration membrane sealing bag 5, a beaker 6 and a constant-temperature water tank 7.
The cantilever clamp 3 comprises a cantilever, a clamp and a vertical connector. The cantilever 31 is a cylinder made of metal, and one end thereof is an external thread head. The clamp comprises a buckle 32 and two fastening knobs XN, the buckle 31 is provided with a supporting column clamping groove and a cantilever clamping groove, and the two fastening knobs XN are respectively connected to the side walls of the two clamping grooves.
The vertical connector 33 comprises a cylinder 331 and a boss 332 of a side arm thereof, wherein the lower end of the cylinder is provided with a vertical internal threaded hole, and the frustum is provided with a horizontal internal threaded hole.
The lower pressing scale column 4 is a cylinder made of PVC hydrophobic plastic, the upper end of the lower pressing scale column is provided with an external thread head, and the lower end of the lower pressing scale column is provided with a fixing ring 41. The range of the lower plunger scale 4 of the embodiment is 10-50ml, the minimum scale is 0.1ml, and the scale compensates and corrects the volume of the fixed ring at the bottom. The material of the fixing ring 41 is copper or stainless steel, and the surface thereof is polished. The use of the downward pressing scale column 4 can reduce the errors generated by system errors and manual operation, and is favorable for further improving the accuracy of the measuring result.
The ultrafiltration membrane sealing bag 5 comprises a bag body 51 and an airtight sealing strip 52 at the upper end of the bag body, and a lifting rope 53 is fixed on the bag body. The PES hydrophobic permeable membrane is made of polypropylene and consists of thousands of tiny hollow fibers, the aperture is 0.01 micron, and the water permeability is 300L/h. PES hydrophobic permeability membrane is food level polypropylene material, has stopped secondary pollution, and polyacrylonitrile membrane silk can wash the use repeatedly, has reduced the waste of experiment consumptive material. The high-precision filtration of the ultrafiltration membrane can reach 0.01 micron, and substances with the grade of colloid, organic matters and the like can be intercepted by the ultrafiltration membrane with the diameter, so that the light aggregate powder with the micron grade can be intercepted by 100 percent, and the escape of sample powder is avoided. The quantity of the fiber yarns is large, so that the water permeability can reach 300L/h, the water permeability is excellent, the complete infiltration of the powder particles and water is accelerated, and the micro-bubbles are prevented from remaining among the powder particles.
The beaker 6 of this example is a glass beaker with a specification of 250ml and a minimum scale of 0.1ml, and is estimated to be 0.01 ml.
The horizontal base 1 of this embodiment is a rectangular base made of metal, and a support column 2.
When the device is assembled, the supporting column 2 is vertically fixed on one side of the horizontal base 1. The external thread head at one end of the cantilever 31 is screwed into the horizontal internal thread hole on the vertical connecting piece 33, and the external thread head at the upper end of the downward pressing scale column 4 is screwed into the vertical internal thread hole on the vertical connecting piece 33. The support post clamping groove of the buckle 32 is sleeved on the support post and is screwed down by a fastening knob. The free end of the cantilever 31 is then inserted into the cantilever-holding groove of the catch 32, tightened by the tightening knob and the levelness of the cantilever adjusted. The cantilever clamp 3 has been fixed to the support post 2 so far, the lateral position of the down-pressing scale post 4 has been determined.
The following are the specific steps for the measurement using the assembled device described above:
(1) standing the sealed bag on a balance, and measuring its dry mass m1. Adding appropriate amount of clean water into beaker, preferably 1/2-2/3, placing into constant temperature water tank, standing, and measuring total volume v of beaker and water1. The standing time is about 20min, based on the stable water temperature in the beaker.
(2) A lifting rope of the ultrafiltration membrane sealing bag is tied on a fixing ring at the lower end of the downward pressing scale column, a fastening knob for clamping the supporting column is adjusted, the cantilever clamp is made to slowly descend along the supporting column, the downward pressing scale column carries the fixed ultrafiltration membrane sealing bag to be slowly immersed into a beaker filled with water, and bubbles are prevented from being brought in the downward pressing process.
(3) And placing the adjusted device and the beaker into a constant-temperature water tank for standing, wherein the temperature of the constant-temperature water tank is controlled to be 20 +/-0.5 ℃, and the water in the constant-temperature water tank is enabled to immerse the depth of the beaker 1/2. Reading the scale v on the push-down scale column2And total volume v of beaker and water3. The standing time is about 30min, based on the condition that no micro bubbles are left on the ultrafiltration membrane sealing bag and the sample powder.
(5) putting a proper amount of light aggregate powder sample to be measured into a re-dried ultrafiltration membrane sealing bag, sealing, standing on a balance, and measuring the mass m of the sample2. Injecting proper amount of clean water into the beaker, placing the beaker into a constant-temperature water tank for standing, and measuring the total volume v of the beaker and the water4. The standing time is about 20min, based on the stable water temperature in the beaker.
(6) And tying a lifting rope of the ultrafiltration membrane sealing bag filled with the sample to a fixing ring at the lower end of the downward pressing scale column, and adjusting a fastening knob for clamping the supporting column to enable the cantilever clamp to slowly descend along the supporting column, so that the downward pressing column carries the fixed ultrafiltration membrane sealing sand bag to be slowly immersed into a beaker filled with water, and bubbles are prevented from being brought in the downward pressing process.
(7) And placing the adjusted device and the beaker into a constant-temperature water tank for standing. Reading the scale v on the lower pressure column5And total volume v of beaker and water6. The standing time is about 5 hours, so that no residual micro bubbles are left on the ultrafiltration membrane sealing bag and the sample powder.
in order to verify the measurement accuracy of the device and the method, three measurement experiments are respectively carried out on the density of the fly ash floating bead and the density of the glass bead by the device and the method, and the used raw materials are as follows in parts by weight: 6.4g of fly ash floating beads, 5.8g of fly ash floating beads and 6.7g of fly ash floating beads; glass beads 4.3g, 4.1g, 4.5g, density measurements are shown in the following table:
table of measurement results of powder density of light aggregate
As can be seen from the above table, the difference between the density of the fly ash floating bead in experiment 1 and the density of the fly ash floating bead in experiments 2 and 3 is 0 and 0.01g/cm3The relative error is 1.3%; the difference between the density of the glass microspheres in experiment 1 and the density of the glass microspheres in experiments 2 and 3 is 0.01g/cm30, the relative error is 2.4%. The accuracy of the measurement result is higher. Therefore, the method can be widely applied to the measurement of the density of other lightweight aggregate powder.
Claims (7)
1. The utility model provides a measure light aggregate powder apparent density's simple and convenient device which characterized in that: the device comprises a horizontal base, a support column, a cantilever clamp, a downward pressing scale column, an ultrafiltration membrane sealing bag, a beaker and a constant temperature water tank, wherein the support column is vertically fixed on the horizontal base; the beaker is filled with water with a known volume, the beaker is placed under an ultrafiltration membrane sealing bag correspondingly packaged with a powder sample on a horizontal base, and a cantilever clamp is adjusted to descend, so that the whole device is placed in a constant-temperature water tank for heat preservation after a scale column is pressed downwards to press the ultrafiltration membrane sealing bag into the water in the beaker.
2. The simple apparatus for measuring the apparent density of lightweight aggregate powder according to claim 1, wherein: the cantilever clamp comprises a cantilever, a clamp and a vertical connecting piece, the clamp comprises a buckle and two fastening knobs, the buckle is provided with a support column clamping groove and a cantilever clamping groove, and the two fastening knobs are respectively connected to the side walls of the two clamping grooves.
3. The simple apparatus for measuring the apparent density of lightweight aggregate powder according to claim 2, wherein: the horizontal base is a rectangular base made of metal, the support column and the cantilever are cylinders made of metal, and the downward pressing scale column is a cylinder made of PVC hydrophobic plastic.
4. A simple device for measuring the apparent density of lightweight aggregate powder according to claim 3, characterized in that: one end of the cantilever is an external thread head, the upper end of the downward pressing scale column is an external thread head, and the lower end of the downward pressing scale column is provided with a fixing ring.
5. The simple apparatus for measuring the apparent density of lightweight aggregate powder according to claim 4, wherein: the range of the downward pressing scale column is 10-50ml, the minimum scale is 0.1ml, and the scale compensates and corrects the volume of the fixed ring.
6. The simple apparatus for measuring the apparent density of lightweight aggregate powder according to claim 4, wherein: the vertical connecting piece comprises a cylinder and a boss of a side arm of the cylinder, the lower end of the cylinder is provided with a vertical internal thread hole, the boss is provided with a horizontal internal thread hole, one end of the cantilever is fixedly connected into the horizontal internal thread hole through an external thread head, and the upper end of the downward pressing scale column is fixedly connected into the vertical internal thread hole through the external thread head.
7. The simple apparatus for measuring the apparent density of lightweight aggregate powder according to claim 4, wherein: the ultrafiltration membrane sealing bag comprises a bag body and an airtight seal at the upper end of the bag body, wherein a lifting rope is fixed on the bag body and is bound on the fixing ring through the lifting rope.
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CN201920348803.4U CN209945934U (en) | 2019-03-19 | 2019-03-19 | Simple device for measuring apparent density of light aggregate powder |
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
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CN109781581A (en) * | 2019-03-19 | 2019-05-21 | 中南大学 | A kind of simple device and its application method measuring light-weight aggregate apparent powder density |
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CN109781581A (en) * | 2019-03-19 | 2019-05-21 | 中南大学 | A kind of simple device and its application method measuring light-weight aggregate apparent powder density |
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