HOTLINE 0086-29-88606479
  Tel: 86-29-88606479   E-mail: sales@dechuang-auto.com

NEWS

About us

Tank seal for guided wave radar level measurement

DATE: 2015-04-22
BROWSE TIMES: 14

A microwave level gauge for measuring a level of a process material in a tank includes a ceramic seal and a microwave conductor. The ceramic seal is disposed adjacent to an opening in the tank and adapted to isolate circuitry from the process material. The microwave conductor is electrically coupled to the circuitry and extends through the hermetic seal and into the process material in the tank. The ceramic seal and an isolating adapter cooperate to isolate the microwave conductor from the process fluid and from external forces.

Level gauges are generally used in the process control industry to measure the level of material contained in a tank. As used herein, the term “tank” refers to a container, receptacle, vessel or other device for holding gases, liquids or solids. Radar level gauges are often used to measure process fluids or process solid levels in tanks, where the process materials range from benign materials to severely corrosive or abrasive compounds.

One type of level gauge for measuring a level of material in a tank is called a microwave level gauge. Microwaves are high frequency, short wavelength, electromagnetic waves. Microwaves, because of their short wavelengths, tend to travel in straight lines. This property gives rise to their application in radar, where objects are detected by the reflection of microwaves.

Generally, microwave or radar level gauges transmit an electromagnetic pulse into the materials contained within the tank, and measure the level of the process materials using the reflected pulse. As used herein, the term “microwave” refers to a high-frequency electromagnetic wave. The term “microwave pulse” refers to a microwave signal of short duration that is transmitted on a microwave antenna or conductor. The terms “microwave antenna” and “microwave conductor”, as used herein, refer to a conductive structure specifically designed to couple high-frequency electromagnetic energy (or to radiate electromagnetic energy). Typically, the microwave antenna or microwave conductor can both transmit and receive electromagnetic energy.

A microwave level gauge assembly for measuring a level of a process material in a tank with a tank atmosphere, the microwave level gauge assembly comprising:

1. a hermetic seal in contact with the tank atmosphere and fixed over a tank opening to isolate transmitter circuitry from the tank atmosphere, the hermetic seal comprising:

2. a ceramic seal body having an opening sized to receive a microwave conductor;

3. an isolating element disposed over the opening and coupled to the ceramic seal body at a coupling joint; 

4. a brazed seal disposed over the coupling joint for fixedly sealing the isolating element to the ceramic seal body; and

5. a microwave conductor extending through the opening and electrically coupled to the transmitter circuitry on one end and to the isolating element on an opposing end, the microwave conductor being sealed from the tank atmosphere by the hermetic seal.

In a conduction wave guide assembly, the antenna typically extends from a transmitter assembly into the process materials. For example, a microwave pulse travels along the antenna, and is reflected back when the pulse encounters a material with a different dielectric constant. Generally, the pulse is affected by the change in the dielectric constant at the surface of the process material within the tank. Various techniques may be used to analyze the reflected microwave pulse (including, for example, time domain reflectometry).

Since the process materials within the tank tend to be corrosive and are often stored under pressure, there is a process seal positioned between the sensor and the potentially aggressive materials within the tank. Conventionally, an O-ring or a teflon seal was used to isolate the process fluid from the transmitter housing and sensor electronics. In addition to isolating the electronics from the process fluid, such seals were typically constructed of materials selected so as not to cause microwave reflection.

While such seals typically met microwave transmission requirements, the seals were not particularly well-suited for high pressure/temperature applications.



Share to
RELATED NEWS / News More
  • Number of clicks: 1
    2020 - 01 - 03
    With the filial piety makes the winter more warmly On this special day, the 80th birthday of our colleague's father and father was ushered in, and all the family members of Xi'an Dechuang wished the elderly a good health and happiness.Hope that more caring for the elderly and often take your children back home when you are off day, try your best to accompany your parents. Any requirements of radar level measurement, please contact us and send your inquiry as soon as possible.
  • Number of clicks: 4
    2019 - 12 - 31
    On the last day of 2019, let's review the radar level gauges used to measure various cement silosThe most popularly model of DCRD1000A3 Radar level transmitter in cement project.Main features of 26ghz radar level sensor:·Small antenna size, easy to install; non-contact radar, no wear, no pollution.·Almost free from corrosion, foam impact; hardly affected by the change of the temperature, pressure and water vapor in the atmosphere.·Severe dust environment is not likely to affect the work of the high-frequency level meter.·Shorter wavelength can achieve better reflection for the inclined solid surface.·The small field angle and energy concentration, enhanced echo capabilities, and beneficial to avoid  interference.·Minimized measuring blind spot can gain be...
  • Number of clicks: 3
    2019 - 12 - 13
    Busy production of radar level transmitter in Dechuang company 2019.12As the most traditional festival in China -------Chinese Spring Festival is from Jan 24 to Jan 30 in 2020, all the production become much more busier from earlier of December 2019... ( normally for Spring festival, the holiday will last almost one month, which 10-15day on before and after the official holiday ) Welcome, 2020!Come on, Dechuang!
  • Number of clicks: 10
    2019 - 12 - 05
    Hello, December!Just the beginning of the month, Our company ushered in gratifying results! WOW! One order, signal model of radar level transmitter, the total amount exceeding RMB2,000,000! TWO MILLION!Proud of outstanding Dechuang employees!The company celebrated the big order, and sent a health pot to each employee in the cold winter, so that everyone in Dechuang family feels more warmth. Dechuang people will work harder to provide customers with better products and better services.Let us work together to meet a better 2020!
  • Number of clicks: 18
    2019 - 11 - 27
    Air purge+Nuzzle ,  Universal joint:The necessary adjunct when measuring the level of bulk solid in silos bins and tanks.When radar level gauge measure the level of solid medium, such as grains, cement powders, solid particles,  the solid material  will form a stockpile or hopper in the silo when feeding  or undloading. Then the antenna of the radar level transmitter need to perpendicularly alignment to the medium surface,  if the material is uneven,  and the heap angle is large then the universal joint flange is needed to adjust the horn angle to aim the charge level.(Due to the inclination of the solid surface it will cause the problem of  echo decay or even the signal loss.)                      &#...
Email:sales@dechuang-auto.com
Adress:
Tel:86-29 88606479
Fax: 86-29 88385903
B203, Gazelle Valley, No.69 Jinye Rd, Hi-tech zone, Xi'an, Shaanxi Province, P.R.China. 710077
Copyright ©2018 - 2019 Dechuang Electrical Technology Co., Ltd SITEMAP
Rhino Cloud Provides Enterprise Cloud Services
犀牛云提供云计算服务