The lining material should be selected according to the corrosiveness, wear and temperature of the tested medium:
First, natural rubber (soft rubber)
1, better elasticity, wear resistance and tearing force
2, resistant to general weak acid, weak alkali corrosion
3. Water and sewage
Second, acid-resistant rubber (hard rubber)
It can withstand the corrosion of hydrochloric acid, acetic acid, oxalic acid, ammonia water, phosphoric acid and 50% sulfuric acid, sodium hydroxide and potassium hydroxide at normal temperature, but it is not resistant to corrosion by strong oxidants.
It can measure general acid, alkali and salt solutions.
Third, neoprene (Neoprene)
1, excellent elasticity, high tearing force, good wear resistance
2, resistant to general low concentration of acid and alkali, salt solution corrosion, but not resistant to oxidation of the medium, and temperature requirements <80 ° C;
It can measure water, sewage, mud and pulp.
Fourth, Polyurethane (Polyurethane)
1, excellent wear resistance
2, poor acid and alkali resistance, temperature requirements <40 ° C
Measure medium-strongly worn coal slurry, mud and slurry
Five, polytetrafluoroethylene (PTFE)
1. Boiling hydrochloric acid, sulfuric acid, nitric acid, aqua regia, concentrated alkali and various organic solvents
2, good wear resistance, poor bonding performance, temperature requirements -80 ~ +180 ° C;
Measuring concentration, concentrated alkali strong corrosive solution and sanitary medium
Gas turbine flowmeter and screwing vortex flowmeter measurement difference
Keywords: gas turbine flowmeter, Tianxin gas turbine flowmeter, gas gas turbine flowmeter
First, the characteristics of gas turbine flowmeter and spiral vortex flowmeter
Gas turbine flowmeter and screwing vortex flowmeter are the main gas metering instruments in China. In foreign countries, almost no one uses gas to swirl into the vortex flow meter. At present, there are certain applications in the domestic vortex flowmeter. In terms of standard conditions. The international standard ISO9551 promulgated by the International Organization for Standardization and the international recommendations R6, R32 promulgated by the International Organization of Legal Metrology (OIML) have corresponding national standards and regulations in China and developed countries. The above documents guarantee the authority of gas turbine flowmeters in gas metering. Sex. Gas-introducing vortex flowmeters have not yet established relevant standards. It is difficult to guarantee the authority of the flow meter in gas metering. At present, in domestic flow meters for gas measurement, gas turbine flowmeters dominate, and the vortex flowmeters also have a certain market. The use of the two is similar, and users often have doubts about the choice of the two.
Selection of measurement types for special industrial and commercial users
I. Introduction
At present, there are some special users in the supply of industrial and commercial users. On the one hand, the gas points are more dispersed, and the amount of gas used in a single combustion device is small (generally 2 to 9 m3/h); on the other hand, the total amount of gas used is Very large, there are many problems with the accurate measurement of the natural gas supply of such users. This type of industrial and commercial users have multiple fuel appliances with different gas consumption. Different gas consumption at different time periods brings certain difficulties to the accurate measurement of natural gas. Under the condition of satisfying the maximum gas consumption, it cannot be measured under the condition of small flow. The problem.
1. Case 1: A large shopping and entertainment mall
The mall has 22 gas points distributed on the second, fourth and fifth floors. In order to ensure the accuracy of natural gas measurement, the gas supply system has a master meter (turbine flow meter Q650) and 22 sets of compensation functions. As a metering table, the flow meter usually has a gas consumption of about 400m3/d and a holiday of about 800m3/d. It is found through the data collection that the total number of meters and sub-meters is about 17m3 per day; in the initial 54d. The cumulative gas consumption of the master meter and the minute meter differs by 11511.80 m3.