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

Application site selection

1. Understand the process parameters

(1) Understand the name of the liquid to be tested (provided by the user)

(2) Understand the maximum flow rate, common flow rate, and minimum flow rate of the liquid to be tested (provided by the user)

(3) Understand the process diameter (provided by the user)

(4) Understand the medium temperature (provided by the user)

(5) Understand the medium pressure (provided by the user)

(6) Understand the conductivity of the fluid to be tested (provided by the user)

(7) Understand whether there is a negative pressure condition (provided by the user)

 

   2. Preliminary selection

(1) Determine whether to use an electromagnetic flowmeter (determined by the salesman) based on the name and nature of the measured medium

Note: Electromagnetic flowmeters can only measure the flow of conductive liquids, while gases, oils and most organic liquids are not in the case of general conductive liquids.

(2) Determine the electrode material based on the known properties of the medium

Note; the company generally provides four kinds of electrodes, such as stainless steel, Hastelloy, titanium and tantalum. Which electrode should be used according to the nature of the medium.

(2) Determine whether rubber or PTFE liner is used according to the temperature of the medium (determined by the salesperson)

Note: rubber temperature should not exceed 80C;

PTFE temperature resistant 150C, instant resistance to 180C;

Urban sewage can generally be rubber lining and stainless steel electrodes

(3) According to the known medium pressure, select the body flange specification (determined by the salesperson)

Note: The specifications of the electromagnetic flange are usually when the diameter is from DN10-250, the rated pressure of the flange is ≤1.6Mpa;

When the diameter is from DN250-1000, the rated pressure of the flange is ≤1.0Mpa;

When the actual pressure of the medium is higher than the above-mentioned pipe diameter-pressure corresponding range, it is a special order, but the maximum pressure shall not exceed 6.4Mpa.

(4) Determine the conductivity of the medium

Note: (1) The conductivity of the electromagnetic flowmeter must not be lower than 5uS/cm.

(2) The conductivity of tap water is about tens to hundreds of uS/cm. Generally, boiler soft water (deionized water) conducts electricity, and pure water (highly distilled water) does not conduct electricity.

(3) The conductivity of gases, oils and most organic liquids is much lower than 5 uS/cm and is not conductive.

3. Understand user requirements

(1) Understand whether it is a combined local display or a split remote display (provided by the user)

Note: Please understand the maximum distance when displaying for remote remote transmission. The maximum distance is 100 meters.

(2) Know if additional features are required (provided by the user)

Note: 1. The electromagnetic flowmeter itself has upper and lower limit flow alarm, frequency and current output functions, no special order is required.

2. The electromagnetic flowmeter housing seal protection grade is IP65 and IP68. When selecting the submersible IP68, it is a special order.

3. When the electromagnetic flowmeter is to be connected to the computer, the RS-485 communication port needs to be added, which is a special order.

4. Selection: After the above steps, the model specifications of the electromagnetic flowmeter can be finalized.