Flow Meter for Steam Service

This may NOT be possable...

Let's start here..

Saturated or Superheated steam?

What is your max Flow Rate?

What is your Min Flow Rate?

What is your process temp?

What is your Process Pressure?

What is the physical environment like, ie. What does the run to and the run after the planed installation site look like?

hi ducdude, first of all thanks for replying. Process parameters are: line size is 16 inches. Ambien t temperature is 5 to 45 degree centigrade. Operating pressure is 4/4.5/5.5 kg/cm2g min/ nor/max respectively. Operating temp is 150/160/180 degree centigrade min/nor/max. Flow is 1.8/10/40 min/nor/max. velocity is 1:84/9:48/38:96 m/s. There is no problem of straight run. May be this data is sufficient. Waiting for your reply.

Hi .....

A few Questions:

1. What are you're flow units?

2. I am assuming that your pressure units kg/cm2g is a typo and you meant to say kg/cm2? Please confirm..

3. Type of steam: Sat or Super heated steam? (Please confirm)

If we are talking Sat Steam then:

4 - 5.5 kg/cm2 equates to 151-161.4 C

If we are talking Super heated steam:

56psiG - 150.9C

78.25psiG - 161.4C

---------------------------------

So we have:

Line size: 16"

Flow: 1.8 - 40 (Need Flow Units)

Amb. Temp: 5 - 45C

Process Temp: 150-180C

Process Pressure: 4 - 5.5 kg/cm2 (56 - 78.25 psig)

Velocity: 1.84 - 38.92 m/s (6.03 - 127.96 ft/s)

Cheers,

Duc

hi ducdude, flow unit is ton/hr. Pressure unit is kg/cm2, significance of g was, it is only showing that pressure is in gauge. I dont know whether steam is saturated or supereated but please tell me what is the significance of this.

Iris is correct: a 40:1 turndown requirement almost certainly excludes any type of pressure-based flow element (orifice, venturi, pitot, etc.) due to their nonlinear characteristic. I've heard of vortex being used successfully on steam, if the low-flow cutoff isn't a problem for your application.

If all you need is total flow through the boiler (i.e. you don't need to independently measure feedwater and steam flow), you could get an approximate measurement of steam flow averaged over time by measuring feedwater into the boiler. I realize this suggestion is a long shot (not knowing more details of your application), but water flow measurement provides you with more viable options of flowmeters with better turndown (turbine, ultrasonic, PD) than steam flow measurement.

You could look into the flexim ultra sonic flow meter it claims a turn down of up to 100:1 and if you use there wave injectors can with stand temps of up to 400 deg c