Some standard content:
UDC 622. B14/- 817
National Standard of the People's Republic of China
GB/T15605-1995
Guide for venting of dust explosions
Published on 1995-06-19
Implemented on 1996-01-01
Published by the State Administration of Technical Supervision
1 Main content and applicable scope
Referenced standards
Terms and units
Explosion design indicators
High-intensity explosion venting
6 Explosion venting of tanks with pipelines
Storage, hopper weighing food
Low-intensity separation Source of the package
Combustible mixture explosion.
Glucose tablets
11 Opening pressure determination
12 Installation, transformation and maintenance
Appendix A Kendao, channel and long penetrator (supplementary) Appendix B Basic principles of dust explosion (reference material)
Appendix C Explosion resistance of combustible dust (reference material)
National Standard of the People's Republic of China
Guide to pressure relief of dust explosion
Guke for venting dust 1 Main content and scope of application
GRT15605—1995
This standard provides broad guidance for the design and application of dust explosion relief technology in enclosures. This standard is not applicable to the pressure relief of dust explosion enclosures, nor to enclosures with excessive internal pressure due to external flames or other fire sources.
This standard is not applicable to toxic and fusible materials and fire explosions. This standard is not applicable to safety rooms that effectively protect against uncontrolled overheating. This standard is not applicable to pressure relief or civil pressure vents for equipment such as oil-insulated transformers. 2 Reference standards: GB/T15604-1995 GB/T5577-1995 Light dust explosion safety standard GB/T15604-1995 New explosion protection system - Part 1: Determination of explosion index of combustible dust in air 3 Terms and units 3.1 Units This standard adopts the ST system of units. Pressure sheets are gauge pressures unless absolute pressure is otherwise specified. 3.2 Terminology || TT || 3-2.7 Combustible dust cloud Combustible dust cloud, Explosive dust standai mixture A gas-solid mixture of combustible dust and air. 3.2.2 Stoichiometric mixture Stoichiometric mixture A mixture of combustible dust and an oxidant, the concentration of the oxidant being sufficient to completely oxidize the combustible material according to the chemical reaction formula. 9.2.3 Burning welocity The speed at which the flame front moves in the mixture in a direction perpendicular to the flame front when the combustible mixture burns. 3.2.4 Enclosure The object surrounding the combustible dust, which may be a room, building, container, equipment, corridor, etc. 3.2.5 Relief pressure (PR) The maximum pressure value that can be reached in the enclosure when the dust burns at any basic dust concentration. 3.2.6 Maximum required pressure (p/n) is the maximum rate of pressure rise in the explosion venting system over all dust concentration ranges. 3.2.7 Explosion venting pressure rise rate (dp/d) is the maximum rate of pressure rise in the explosion venting system when a certain dust concentration is exceeded. 3.2-a Quantitative rate of reduced pressure rise (dp/d:>rm) The maximum value of the explosion pressure rise during the explosion in all dust chambers. 3.2.9 Opening static pressure (A. The static pressure at which the explosion device on the package body can be opened when the dust explodes. 3.2.1 Explosion venting eqwipment The device installed on the package to realize venting. 3.2.11 Burst pieces are a kind of explosion venting device, which cracks or opens under a certain opening pressure and opens quickly. 3.2-12 Explosion venting door 9icxplosion Doorg is a kind of explosion relief device, which opens under a certain opening pressure and can be closed after the explosion. 3.2.13 Venting efficiency The ratio of the area of the bursting disc required to avoid explosion under the same opening pressure and reach the same large explosion relief pressure in the same network will be called the venting efficiency of the vent. 3.2.14 Vent durl
The duct that transmits the pressure wave and flame of the explosion to the outside of the building. 3-2.15 Hydraulic diameter: If the pipe is long and the cross-sectional area of the duct is convex, the hydraulic diameter can be used to calculate the length-to-diameter ratio. D-4A/P
Where, A-cross-sectional area, n*
\-circumference of the cross-sectional area, m.
3.2.16 Maximum flame length outside the explosion vent maximaummeac hnfllame(r) is the value of the length of the flame ejected from the explosion outlet during explosion venting. 3.2.17 explosion pressure outside explosion venting (xternalpeakprraxeulexpliomcouixitleLluwventingujnirgp) is the pressure at the tip of the explosion flame at a distance from the explosion venting. 3.2.18 maximum explosion pressure outside explosion venting (makimumextertalpeakprtxsure) is the value of the pressure at the tip of the flame ejected from the venting. 3.2.19 dust explosion grade dist The severity of dust explosion can be divided into three levels according to the explosion index K value. See Table 1. (1) MPa. (m/s) 3.2.20 Recoil strength (F) Explosion index K>20, 3.2.30 Recoil strength (F) The maximum recoil force given by the leaking fluid to the filling or retaining parts in the enclosure in the opposite direction of the explosion when the explosion is deep. 3.2.21 Maximum recoil force (F) The maximum recoil force given by the leaking fluid when the maximum explosion pressure occurs. 3.2.22 Enclosure strength The maximum internal pressure that the loudest part of the enclosure can withstand. 2
4 Explosion venting design guide
GB/T15605:1995
4.1 Before designing explosion venting, the applicable standards of this standard should be reviewed to avoid the intentional use of explosion venting requirements. 4.2 Strength and design of the two enclosures
4.2.1 The pressure-resistant design requires that the equipment can withstand the maximum explosion pressure without inelastic deformation and damage. The equipment is designed, tested and marked in accordance with the pressure-resistant design specifications and standards. If the air pressure is increased to a certain degree of atmospheric pressure, the explosion pressure will also increase, and the strength of the equipment should also increase accordingly. 4.2.2 Impact-resistant design means that when an explosion occurs inside the equipment, the equipment is allowed to have some permanent inelastic deformation, but it will not crack. 4.2.3 The main difference between pressure design and impact design is that the allowable stress of the same material is lower in pressure design than in impact design. The allowable stress should not be greater than the value of two-thirds of the explosion strength limit. The explosion venting of low-strength packaging + the pressure resistance of the packaging should be at least 2
4.2.4 When the initial pressure is no more than 0.02MPa higher than the atmospheric pressure, it can be treated as atmospheric pressure. When it is greater than the above value, its maximum explosion force is proportional to the initial pressure (absolute pressure>). However, if it is pressurized by inflatable gas, the explosion pressure decreases with the increase of the pressure in the container. When designing, take the maximum explosion pressure under atmospheric pressure. 4.2.5 If the explosion venting area cannot be opened too high to meet the requirements, the strength of the package should be increased to reduce the required explosion venting area. 4.3 Selection of explosion area calculation method
4.3.1 According to the strong wind of the surrounding package, select the algorithm for the positive area of the package (see Section 5.6.7) or low-strength practical enclosure leakage calculation method (see Section 8)
4.3.2 If the powder explosion index K is known, the explosion index band reading method (see 5.2.1) can be used. When the length m is unknown or a higher safety factor is adopted, the dust explosion level reading method can be used. See 5.2.27. 4.4 The supporting structure of the enclosure must be strong to withstand the recoil force. 4.4.1 The recoil force can be calculated according to formula (2):
F,.n=a-A+ prd,u
Wherein, F.. maximum recoil force.kN
@—dynamic coefficient. Generally, 11D0
A—sliding explosion accumulation, m\
Pa. Measure the leakage pressure MP.
4.4.2 After research by professional explosion-proof design and research units, the actual recoil force F (kN) can be calculated using formula (3): Fr = 61190A-Pmm
Where: 5 is the load factor, and the coefficient of correction is taken into account, and the general band is 6 = 0.52 plus the safety factor 504 = 0.78.
4.4.3 The explosion vents should be as uniform and symmetrical as possible to eliminate the recoil force, 4.5 The design of the operation and installation of the explosion vents
4.5.1 For buildings without special requirements for thermal insulation and moisture retention, the pressure-avoiding effect of the non-covered sensitive opening is the highest and most economical, followed by the shutter. If the requirements for airtightness and opening pressure are strict, the operating pressure is high, and the frequency of leakage is not large, it is appropriate to use bursting discs, otherwise the explosion vents should be used. 4.5.2 The total mass of the movable part of an explosion vent (including insulation materials and fixed installation hardware) should be as light as possible, generally not more than 10kg/m, but it should be avoided to be sucked open by external forces. 4.53 When venting pressure, fragile materials such as mineral cement board or glass should not be used as much as possible, otherwise it should be used to reduce injuries. 4.5.4 The door of the explosion vent must be designed and installed to be able to rotate freely and not be affected by other obstacles. 4.5.5 The explosion vent must be equipped with a guardrail to prevent people from falling in. 4.56 It is necessary to avoid ice accumulation to change the opening force of the vent. 4.5. The location of the vent should be close to the place where the induction source may be generated. It should be installed at the top or upper part of the solid package as much as possible. It should not be directed to flammable and explosive dangerous places to avoid ignition. Other combustibles should not be released to the public to avoid explosion and injury. 3
Gu115605bzxZ.net
351833023RA247
GR/T15605—1995
“通的体
38299212833
E醫尊
CR/T15605—1995
lu\生情通
GB/T 15605-1995
E\net volume
5 Leakage management of high-strength round packages
GH/T15605-1995
5.1 This chapter is used for the calculation of the explosion relief area of the enclosure with a pressure capacity Fr.. equal to or higher than 0.02MPa. 5.2 Calculation of explosion relief area of the package without leakage 5-2.1 Explosion grease number Kno diagram method
5.2.1.1 Range of use
Maximum pressure. Within 0.2~α,2MLP: Normally 0.01 or G.02 or C. 05MP explosion index K is between 1~≤60MPa (m/): S1, S12 grade powder group generally has a maximum explosion pressure of less than 1.1MPa or St3 grade dust generally has a maximum explosion pressure of less than 1.3MPa, the enclosure diameter is not more than 1000m
and the aspect ratio is less than 31
without venting, the initial pressure is the maximum pressure.
5.2.1.2 Calculation based on the vertical model
amplified venting pressure.d
includes the enclosure volume, V:
explosion index, K.
5.2.1.3 Calculation method
Shen school open to find the corresponding reading (see Figure 2. 3>. On the right side of the coordinate system, draw a vertical line upward to intersect the corresponding maximum explosion pressure line of the explosion package according to the required explosion relief. Then draw a horizontal line from the intersection to intersect the explosion index K line. From this intersection, draw a vertical line downward to intersect the mark. The point of the explosion relief is the starting point. 5.2.1.4 Regression formula
Regression formula for explosion index K The regression of the explosion index K is the same as the range of calculation. The calculation formula is as follows; Ay=a-Km.ela..yi.
Sliding pressure surface, m
Use package storage.ml;
Coal explosion index.MPa: (m/s):
....-design volume explosion relief bed.MHa
=3.00u 571exp20pur
&=0.97Rexp1.05u)
=-0.687exp[2.26pu.J
Open static positive, MPa.
5.2.2 Semi-explosion and micro-reading medical law
5.2.2. 1 Scope of application: The explosion pressure is between C.02-0.2M. The opening pressure is 0.01 or 0.02 or 0.05M. 5.2.2.2 According to the national standards for explosion, dust explosion, etc., 5.2.2.3 Calculation method: GE/T15605:1995. The explosion pressure is calculated based on the corresponding dust explosion level (see Figure 1, Figure 6, Figure 6), from the corresponding point of the explosion through the body upward. awMP
hand: the dust
2 items
two can be air
before||tt| ... For example, if the maximum combustion pressure of the equipment with only venting pipe is 0.02MPE, after installing venting pipe less than 3m, the maximum venting pressure will increase to 0.06MPB. This can be obtained from the vertical line drawn from the coordinate 0.02MP in Figure 7 to intersect 0<(or the 3m straight line drawn from this intersection to intersect the vertical coordinate 0<(0.06MPa). The maximum blasting pressure change of the equipment after installing venting pipe can be calculated by formula (5) and (6): When 0.3m,
p\4.a=0. B3(pr.)9.a1
In the formula, the length of venting pipe is
P'md.0.90f pd.y4 +1d
When there is no explosion relief, the maximum explosion relief pressure in the container is MPa. When there is a leakage pipe, the maximum pressure in the container is (5)
+++hh++(6)
GA.T15605—1995
5.3.3 Calculation of explosion area of explosion relief device When installing an explosion relief device, if the strength of the device does not increase, the leakage area must be increased: so that the maximum leakage pressure does not increase. The container strength is 0.06MPa, and a 2.5m long leakage pipe is required. The pseudo-coordinate force mm=D.U6M Draw a horizontal line at P and intersect the 0≤3m oblique line. From this intersection, draw a gravity line downward and intersect the coordinate at pm=0.C2MPa. Then control the explosion relief area of the non-venting section to the explosion relief area required when there is an explosion relief, S: the explosion relief area of the iron explosion relief, m
Figure 6 The dust explosion level diagram with an opening pressure of 0.5MPa can be calculated by the following formula:
015.3m when
pwn=l.330s(pd.).sm
C6m when:
fd.mr=]. 243 6 Pmnm
According to the maximum explosion relief pressure, explosion index K, dust explosion grade St, container volume V, and opening pressure, the required venting pressure is calculated
5.3.4 If a hole is set near the explosion relief device to maintain the pressure and remove debris, the hole and the shell channel must be the same as the explosion relief tube, and must be closed well
5.3.5 Lightweight protective film is used to prevent the explosion relief from invading each other, but the increased opening pressure must be within the allowable range. 5.3-6 The explosion relief arm should have a large cross-sectional area and thickness, at least the surface of the explosion vent and the strength of the fan body. 5.3. The explosion vent should be as straight as possible, generally not more than 3. 5.3.8. The discharge control pipe should be equipped without elbows as much as possible to reduce the resistance of combustion and the time of explosion discharge.
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.