Laser Distance Measure is a very convenient
tool for various types of applications in industries, construction and house decoration.
Laser Distance Meter is a very useful device which gives accurate measurement
of distance, area and volume especially in large areas such as rooms,
apartments, buildings, real estates, factories, warehouses, infrastructures, gardens,
roads, and many other applications requiring accurate results for distance ,
area and volume measurement.
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Specification:
Product
Model:
JX40
Accuracy:
±1.5mm (0.06
inch)
Measuring
Unit:
metre/inch/feet
Measuring
Range:
0.03~40m
(0.01 to 131 ft)
Measuring
Time:
0.1~4
seconds
Laser Class:
Class II
Laser Type:
635nm,
<1mW
Waterproof
& Dustproof :
IP54
Auto Laser
Off:
60 seconds
Automatic
Power-off:
480
seconds(8 minutes)
Lighting:
white LED
Datum
Option:
Can choose
Front edge or end piece edge as datum
Battery
Status:
Y
Signal
Strength Display:
Y
2 inch large
screen
Display
illumination and multi-line display:
Max
2 displays
Data Memory:
Y (allow 20
values)
Backlight
display:
Y
Continuous
Measurement:
Y
Min/max
Measurement:
Y
Addition/Subtraction(Distance/Area/Volume):
Y
Area/Volume/Pythagoras
Measurement:
Y
Battery
Type:
AAA alkaline
battery(2*1.5v )
Weight:
about
80g
Dimensions(L*W*H):
4*2*11.5cm
Auto
correction and error report technology:
Y
Operating
Temperature:
0-40 ℃(32-104 ℉ )
Storage
Temperature:
-20~60 ℃
(-4~140 ℉)
Laser Distance Meter Laser Distance Meter,Laser Distance Measure,Laser Rangefinder,Laser Distance Gauge Chengdu JRT Meter Technology Co., Ltd , https://www.jrt-measure.com
1=SimSun Abstract This paper discusses the calculation of the air volume for the hump reducer. Due to the large selection range of coefficients in the calculation formula provided by the data, the calculation results of different coefficients differ by two or three times. Based on practical experience, the author proposes how to select the coefficient to determine the air volume of a single air compressor and the number of air compressors. The calculation of the air volume of the hump reducer is the main basis for the equipment selection of the hump power room engineering design hollow press. When calculating, determine the air volume according to the type and configuration of the reducer. The calculation is based on the 1 signal design manual 〉〉 and 2 汀 series vehicle reducer 〉〉 two calculations provided in the data. According to the actual situation encountered during the work, the author calculated the air volume of the hump reducer in a certain section of the Jinpu line. Combined with the actual management, I feel that the selection of the air volume of the hump reducer and the air volume of the air compressor have the following questions worth discussing. 1 When selecting the coefficient when calculating the air volume, please refer to the calculation formula in the signal design manual. Reference 1 page 748. When different parameters are selected, the calculation results are compared as follows: the selection of the peak speed is 5 semi-automatically automated than the mechanized 671. When the peak speed is set to 5, the air volume is set to 6 when the air volume is increased by 20, and when the 7th core is selected, the air volume is increased by 40.
When the peak speed is 6kmh, the air volume is l, and when 7kmh is selected, the air volume is increased by 16.
The safety factor 0 ranges from 1.1.2.
When setting the heart = 1. When the air volume is used, the air volume is increased by 9.
The leakage coefficient of the pneumatic system is in the range of 1.1.5.
When the air volume is set to =1.1, the air volume is increased by 9. When the air volume is increased by 9, when the value is set to 1.3, the air volume is increased by 18, and when the frequency is selected by 1.4, the air volume is increased by 27, and when the selection is 1.5, the air volume is increased by 36.
The repetitive braking coefficient selection interval is 1.5, 2, and the destination bit is 2.
When the interval braking gear reducer is type 1, the braking position is 012, and the same number of knots, such as 6 knots, 1 is calculated according to the 4th wind pressure, and the repeated braking coefficient of the interval braking position is 1.5. When the repeated braking coefficient of the braking position is taken as the basic air volume, when the repeated braking coefficient of the interval braking position is taken at the same time, the air volume is increased by 37.
When the braking position of the intermittent braking position reducer is for the type 24 purpose, for the redundant type 24, and the same number of sections, such as 6+6 knots, the repeated braking coefficient of the interval braking position is 1.5, and the target braking repeating braking coefficient is Take 1 for the basic air volume, and increase the air volume by 51 when the braking coefficient of the interval braking position is 2.
According to the range of values ​​in the above four items, the minimum value of the low-end data is compared with the high-end data of the maximum value. When the peak-pushing speed is 7 or less, the minimum amount of the airflow is the peak-pushing speed of 6 At 1 o'clock, when the minimum value is taken to be the maximum 1 air volume, when the peaking speed is 5, the air volume when the minimum value is the maximum value is calculated from the above, and the value is different, and the air volume of the reducer is different. Times, 2.9 times. By choosing different coefficients, the results calculated by the formula vary greatly. In this way, different designers have a maximum difference of nearly three times the amount of air used to calculate the hump field of the same scale. Such a result will have a greater impact on the engineering investment and construction and operation of the next stage. The coefficients have a large range of values ​​and are worth discussing. According to the actual use situation, it is necessary to comprehensively consider and determine the reasonable value. The calculation of the air volume is not significantly different from the actual air volume.
2 Discussion of the calculation results The qualitative analysis of the above calculated results, the following discussion considers the minimum value of each coefficient, the large corpse is calculated, the calculation of each coefficient in the formula when the minimum value has been calculated, the calculation has increased 22 than the actual air volume. Wealthy amount.
The calculated air volume is the total air volume of the hump. When selecting the air exhaust volume of the air compressor, the air volume of a single air compressor should be less than the total air volume.
The selection of each coefficient in the calculation formula should be determined according to the actual situation of the hump field. For the large hump with 2 north peaks in the number of 2000 vehicles with seven, the coefficient can be selected larger, less than 2000, the coefficient can be smaller. .
The calculation of the instantaneous air volume of the hump should not be used as the basis for engineering design to select the air compressor. The calculation of the storage volume should be considered when determining the air volume of the air compressor. The calculation of the storage volume is not discussed here. According to the actual maintenance, the storage volume is preferably slightly larger than the calculation volume. Generally speaking, when the volume is larger. The instantaneous wind fluctuation of the air supply system is small, which can make up for the determination of the instantaneous air volume of the air compressor and the air exhaust volume and the number of air compressors. At present, the relationship between the air volume and the number of air compressors is well combined, and there is no clear regulation. According to the previous practice, when a single air compressor works to meet the normal air volume, it is equipped with a main machine and a auxiliary machine. When the hump in the hub area disintegrates more than 4,000 vehicles every day and night, an additional air compressor should be added as a backup machine to improve the reliability of the power system equipment. This is because the air supply station is reliable, and the entire hump field The shunting operation is crucial, so there must be a certain amount of redundancy.
The determination of the air volume of a single air compressor, in addition to the calculation of the air volume, but also according to the size of the hump field every day and night disintegration, comprehensive consideration. The effect of lOm3min is good. This is determined by the operating cost factor of the air compressor. In the case where the storage volume is determined, the exhaust air volume is too large, which will cause the air compressor to start and stop frequently; if the exhaust air volume is too small, the air compressor working time will be too long.
At present, the operating units use asset management as the main mode of transportation production, and have abandoned the pursuit of a large and comprehensive approach to transportation equipment. Pursue reasonable assets on the basis of safety, while new equipment meets the needs of transportation capacity, while minimizing the operating expenses of equipment. Therefore, it is the concern of the operation takeover unit to reasonably determine the air volume of the hump field. If the calculation is too large, the increase of unreasonable investment, including the equipment cost, the power room should increase the power capacity, etc., and the operating expenses after the two productions increase Large power consumption increases the expenditure on accessories materials and so on. If the calculation is too small to meet the needs of transportation, it will directly affect the number of humps compiled and reduce the hump efficiency.
For example, calculate the air volume of a 14-row hump field. The hump is set with an interval braking position of TJK type 5+6, the target braking position 耵, 0 type 6+6, and the peaking speed is set to 6. The most brake level 4 working wind pressure calculation, when using low-end data calculation, the wind volume is 26!3, when using high-end data calculation, the air volume is 573, and the high and low end calculation air volume is 2.2 times. According to the configuration of three 10,13 air compressors, it can fully meet the needs. If the design is 20 air compressors, the air volume of the air compressor is significantly larger than the actual air volume. The actual situation is that the air volume is much smaller than the air volume calculated using the low-end data. Therefore, the design should be calculated according to the specifications and from the actual situation, and can be reasonably calculated to meet the needs of transportation.
1. Railway workers, technical design manual. Signal, China Railway Publishing House, 1993.