GB 11639-1989 Method for determination of technical indicators of porous packing for dissolved acetylene gas cylinders
Some standard content:
National Standard of the People's Republic of China
Dissolved acetylene cylinders
Methods for determination of technical indicators of porous fillers
Methods of test for porous mass of dissolved acetylene cylinders1 Subject content and scope of application
GB11639 -89
This standard specifies the method for measuring the compressive strength, bulk density, porosity, surface pores, internal pores, total clearance and shoulder axial clearance of porous fillers.
This standard is applicable to the determination of technical indicators of integral calcium silicate porous fillers in dissolved acetylene cylinders. Note: The measurement ambient temperature for the measurement methods specified in this standard refers to room temperature. 2 Reference Standards
GB11638 Dissolved Acetylene Cylinders
3 Terms
3.1 Samples
Cut test blocks that meet certain size requirements from the porous filler (hereinafter referred to as the filler) . 3.2 Compressive strength
The maximum load per unit area when the sample is compressed by 10% in the height direction at room temperature. 3.3 Bulk density
For a sample, it refers to its mass per unit total volume. For the filling in the cylinder, it refers to the average mass of the filling per unit volume of the cylinder. Note: The total volume refers to the sum of the solid volume and pore volume in the sample. 3.4 Porosity
For a sample, it refers to the percentage of the volume of all its pores (open pores that can communicate with the atmosphere) to the total volume. For the filling in the cylinder, it refers to the percentage of the sum of the volumes of all pores, gaps, and holes and the actual volume of the cylinder. 3.5 Total gap
Observed on the longitudinal section of a cylinder filled with filler, the sum of the widths of the two corresponding gaps between the filler and the inner wall of the cylinder. It is divided into axial total clearance (measured along the axial direction) and radial total clearance (measured along the radial direction). 3.6 Shoulder axial clearance
The gap width between the upper surface of the packing in the cylinder and the inner wall of the upper head of the cylinder. 3.7 Holes
Surface holes refer to the pits visible to the naked eye produced on the surface of the overall filler during the manufacturing process. Internal holes refer to the pits visible to the naked eye when viewed on the transverse section of the overall filler. Approved by the State Bureau of Technical Supervision on 1989-09-21 and implemented on 1990-06-01
4 Summary of method principles
4.1 Determination of compressive strength
GB11639-89
Using pressure The testing machine loads and compresses a sample of a certain size at a specified speed until it is compressed to 90% of its original height. The compressive strength of the filler is calculated based on the maximum load value and sample size indicated by the testing machine. 4.2 Volume Density Measurement
Weigh the dried mass of the filler, and calculate the volume density of the filler in the sample or cylinder based on the sample size or the actual volume of the cylinder. 4.3 Porosity determination
Weigh out the mass of moisture absorbed by the sample after boiling or weigh out the mass of moisture lost by the filler in the cylinder. According to the size of the sample or the actual volume of the cylinder, calculate the porosity of the filler in the sample or cylinder respectively. 4.4 Measurement of surface hole volume
After filling and repairing the holes on the surface of the filler with a certain amount of rubber clay, the volume of the holes on the surface of the filler can be indirectly calculated by weighing the mass of the remaining rubber clay.
4.5 Internal hole surface diameter measurement
Use a graduated 10x magnifying glass to measure the internal hole surface diameter. 4.6 Measurement of total clearance and shoulder axial clearance
Use a special feeler gauge to directly measure the packing gap. 5 General Provisions
5.1 Measuring instruments should be regularly calibrated.
5.2 The solution of the bottle used for testing the technical indicators of the filler (hereinafter referred to as the testing bottle) should not affect the determination of the technical indicators. 5.3 Sampling methods and tools should not change the performance of the filler. Generally, a machine band saw or a manual saw can be used. 5.4 The appearance of the sample shall be free of missing edges, corners, cracks caused by sample preparation, and other defects that may affect the determination of filler technical indicators. 5.5 When measuring with balances, bench scales (including electronic scales) and vernier calipers, the results should be accurate to one decimal place after the unit of measurement. 6 Instruments and Equipment
6.1 Pressure testing machine: Mechanical or hydraulic material testing machine can be used and should meet the following requirements. It has a control system that uniformly and continuously increases the load; a.
should be able to automatically indicate and record the maximum pressure endured by the sample; b.
The force measurement indication error shall not be greater than ±2%;| |tt||c.
The compressive load value should be between 10% and 90% of the full scale of the testing machine dial. d.
6.2 Drying box: with automatic constant temperature control device. 6.3 Balance: The maximum weighing capacity is not less than 1000g, and the graduation value is 0.1g. 6.4 Platform scale (or electronic scale); the maximum weighing should be 1.5 to 3.0 times the actual weighing, and the minimum graduation value (or minimum display value) should not be greater than 0.2kg.
6.5 Water container: aluminum pot or stainless steel pot with a capacity of not less than 3 liters. 6.6 Measurement simple: 50mL (or 100mL).
6.7 vernier caliper.
6.8 electric stove.
6.9 electric drying box.
6.10 Right square (or ruler).
6.11 Plasticine.
2 special feeler gauge. See Figure 1.
6.12
R2.5
G31163989
Print in size A
Working
R
Sharp edges are blunted
Material, stainless steel
Figure 1 Special feeler gauge
The specifications of dimension A (thickness) of the special feeler gauge for acetylene bottle series products are: general dimensions are used according to Table 1, and only gauge dimensions Select according to Table 2. Table 1 General size A
0.3
Nominal volume of block bottle
L
Size A
mm
0.5||tt| |10
0.8
1.4
1.8
0.7
Note: Feeler gauges with the same size A do not need to be duplicated. 7 Sample preparation and dimensional plastic testing
Table 2
16
0.9
1.7
2.3
1.5
Gauge size A
25
1.8
1.0
2.1
2.8
7.1 Preparation
Filling from testing After taking out the whole bottle, prepare a sample 2.1
40
1.1
2.6
3.1
mm| in the middle of the filler as shown in Figure 2. |tt||2.4
60
1.3
2.6
3.1
7.1.1 Compressive strength specimen:
125| |tt||GB11639—89
Figure 2
1 - Compressive strength sample; 2 - Volume density and porosity sample 7.1.1.1 Size: 100mm axial). 7.1.1.2 Quantity: 1 piece.
7.1.1.3 Requirements: The load-bearing surface of the specimen should be flat. When the sample is inspected on a flat plate, its non-verticality tolerance and non-parallelism tolerance are not greater than 3mm.
7.1.2 Bulk density and porosity sample:
7.1.2.1 Size: 50mm×80mm×125mm. 7.1.2.2 Quantity: 1 piece.
Note: When bulk density and porosity are tested separately, the number of samples should be 2. 7.1.2.3 Requirements: All surfaces of the specimen should be smooth. When inspecting with a ruler, the gap between the straight edge of the ruler and any side of the specimen shall not be greater than 1 mm.
7.2 Dimensional measurement
The measurement of each size of the sample should be carried out in the middle of each geometric plane, and each size should be measured twice on the corresponding surface of the same part. Take its arithmetic mean.
8 Measurement steps
8.1 Measurement of technical indicators of filling in bottles for testing Measurement items: total clearance, surface pores, internal pores, compressive strength, volume density of the sample, and porosity of the sample. 8.1.1 Determination of total clearance:
8.1.1.1 Open half of the bottle shell along the axis of the testing bottle, and use a special feeler gauge to measure the total axial clearance and the total radial clearance respectively. 2 to 4 groups should be selected for measurement. corresponding measuring points. The number of measurements at the same measuring point for a feeler gauge of the same specification should not exceed two. 8.1.1.2 The maximum measured value is the measurement result of the total clearance. 8.1.2 Determination of surface pore volume:
8.1.2.Determination of the volume of 130cm2 plasticine: Use a 50mL (or 100mL) measuring tape to fill it with 20mL (or 70mL) of distilled water, and then put the plasticine into the measuring tape (distilled water must not be splashed). Make the liquid level scale stop exactly at 50mL (or 100mL). Pour out the distilled water and take out the plasticine. Blow dry the water attached to the surface (or use gauze to absorb it). Weigh out the mass of the plasticine and seal it in a plastic bag for later use. 8.1.2.2 Measurement of the volume of a single hole on the surface: Use a known volume of plasticine to fill and repair the largest single hole on the surface of the filler until the plasticine on the surface of the patched hole is flush with the surface of the filler on the edge of the hole. Weigh the remainder. Lower quality of plasticine. Calculate the volume of a single hole on the surface according to formula (1): Volume of a single hole on the surface, cm\;
where.V
mo
mi
-30cm plasticine The mass > g;
GB11639-89
30
2. (mo mi)
mo
The mass of plasticine remaining after repairing a single hole , g; 30-known volume of plasticine, cm.
The calculation result retains two significant digits.
(1)
8.1.2.3 Determination of the total volume of surface holes. Use the remaining plasticine to continue filling all the remaining fire holes on the repaired surface according to the method in 8.1.2.2, and weigh out the final remaining volume. The quality of plasticine. Calculate the total volume of surface holes according to formula (2):
V
where: ZV—total volume of surface holes, cm\;30
mo
(mom2)
m2-The final mass of plasticine remaining after filling and repairing the hole for the second time, g. Calculation results retain two significant digits.
8.1.3 Determination of the surface diameter of the internal holes: (2)
After the overall filler is cut transversely as shown in Figure 2, use a 10x magnifying glass (or a measuring microscope with a 20x magnification) to measure four arbitrary The surface diameter of the hole in the cross section, where the maximum plane distance between any two points of the largest hole is the measured value of the maximum diameter of the internal hole (when the diameter exceeds the measurement range of a 10x graduated magnifying glass, a ruler can be used instead). 8.1.4 Determination of compressive strength:
8.1.4.1 After measuring the length, width and height of the sample according to 6.2, dry it in a drying oven at 150°C for 2 hours, remove it and place it in a desiccator ( Or seal and package in plastic bags) and cool to room temperature.
8.1.4.2 Place the sample vertically in the center of the lower pressure head with a pressure plate. Place the upper end of the sample on the pressure plate and then adjust the testing machine so that the upper pressure head of the testing machine is just in contact with the upper pressure plate. , determined as the zero point of deformation. Compress the filler sample uniformly at a loading speed of 0.1 to 0.5 N/mm2·s. When the sample is compressed to 90% of its original height, the test stops immediately. Record the maximum load indicated on the force measuring dial of the testing machine at this time.
8.1.4.3 Calculate the compressive strength according to formula (3): de
where: .
Compressive strength, N/mm2;
F—maximum load, N;bzxz.net
A—compression area of ??the specimen, mm2.
Test calculation results retain two significant digits. 8.1.5 Measurement of bulk density of the sample:
F
(3)
8.1.5.1 After brushing off the surface dust of the sample, measure the length and width according to Article 7.2 , high size, put it into a drying box, dry it at 150℃ to constant weight, take out the sample and put it into the desiccator, cool it to room temperature, and then weigh the mass of the sample. Note: Constant weight means that the difference between the two weighings of the sample during the drying process is less than 0.1% of the mass of the sample. 8.1.5.2 Calculate the volume density of the sample according to formula (4): e
where: p-
volume density, g/L;
V
· (4)
m, the mass of the sample after drying, g;
I—the total volume of the sample, L.
The calculation result retains three significant digits.
8.1.6 Determination of porosity of the sample:
GB11639-89
8.1.6.1 Place the sample with measured bulk density into a water container (can be at the bottom of the container First put on no less than five layers of clean gauze), fill it with tap water that can filter out the sample, heat it on an electric stove, boil continuously for more than 5 hours (the boiling should not be too violent), cool naturally and let it stand for no less than 12 hours. , so that the sample absorbs water and reaches saturation (the sample is always submerged in water). Take out the sample, immediately use multi-layer gauze full of water to remove excess moisture on the surface of the sample (be careful not to suck out the water in the pores of the sample), weigh and record the mass of the sample in this state, 8.1.6.2 according to formula (5 ) Calculate the porosity of the sample: g = (m2*) . 100%
V.
where: o,-
mg
porosity, %;
Sample mass under saturated moisture state, 8;
u—specific volume of water, value 0.001L/g.
The calculation result retains two significant digits.
8.1.6.3 When one of the following situations occurs, the method given in Appendix A can be used to determine the sample volume. a. The sample has defects not caused by sample preparation;
b. Arbitration measurement.
8.1.6.4 During the measurement of sample porosity, if one of the following situations occurs, the measurement results will be invalid. a.
The area of ??any corner of the sample that is collapsed or damaged is approximately greater than 0.5cm2; the volume of the sample’s disintegration or falling off mass is approximately greater than 0.5cm. b.
8.2 Determination of technical indicators of the filler in the cylinder
Measurement items: shoulder axial clearance, volume density of the filler in the cylinder, and porosity of the filler in the cylinder. 8.2.1 Determination of shoulder axial clearance:
(5)
Use a special feeler gauge to measure the shoulder axial clearance at the mouth of the cylinder filled with filler. The plane angle differs by approximately 120°. It is carried out at three points, and the maximum measurement value is the measurement result of the shoulder axial clearance. The number of measurements at the same position with a cold ruler of the same specification should not exceed two times. 8.2.2 Determination of the volume density of the filler in the cylinder: Weigh the mass of the cylinder (bottle shell) and the dried mass of the cylinder filled with filler. Calculate the volume density of the filler in the cylinder according to formula (6): Pe
Where: Volume -
Volume density of the filler in the cylinder, g/L;
m--| |tt||The dried mass of a filled cylinder, kg. The texture of the cylinder (shell).kg:
m
■ Actual volume of the cylinder, L.
The gram calculation result retains three significant digits.
8.2.3 Determination of the porosity of the filler in the cylinder
Weigh the mass of the cylinder after grouting and the mass after baking. Calculate the porosity of the filler in the cylinder according to equation (7): .1000
=(m,-m,):r.1 000
.100%
(6)
7)
:. Porosity of the filler in the cylinder, %; m, mass of the cylinder after grouting, kg.
The calculation result retains two significant digits.
9 Number Rounding
GB11639--89
When calculating the measurement results, the value after the remaining significant digits should be in accordance with Articles 3.1~3.3 of GB8170 "Rules for Rounding Numbers" The measurement report shall be revised according to the provisions of Article 4.1, and the measurement report shall not be revised for 10 consecutive times according to the provisions of Article 4.1
The measurement report shall include the following content:
Commissioning unit;
b. Sample name;
Measurement items;
C
The batch, kettle (device) number and cylinder number of the sample: d.
The actual measured size of the sample ;
e.
Measurement results;
f.
g: Measuring personnel;
Report date.
h.
GB11639-89
Appendix A
Volume determination by buoyancy weighing method
(reference)
This appendix is Additional method for determining the volume of the sample when measuring the porosity of the filler sample by the water boiling method A1 Summary of method principle
The buoyancy of an object in water is equal to the mass of water displaced by the object. According to the specific volume of water, it can be calculated indirectly Find the volume of the object to be measured A2 method steps
A2.1 Hang the boiled and cooled (saturated with moisture) sample with a nylon thread, and hang it in a container with an overflow pipe filled with distilled water In a container (or other container containing enough distilled water to completely immerse the sample), hang the other end of the nylon thread on the balance and weigh the mass of the sample in the water.
Note: Distilled water can also be replaced by ordinary tap water in place of A2.2. Calculate the sample volume according to formula (A1):
V, - (m. - m.) . ....
Where: me—the mass of the sample in distilled water, g. Additional notes:
This standard is proposed by the Ministry of Labor of the People's Republic of China. This standard is under the jurisdiction and interpretation of the National Gas Cylinder Standardization Technical Committee, and the state-owned Changzheng Machinery Factory is responsible for drafting this standard. The main drafter of this standard is Chen Zhuliang.
(AI)
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