Need Unusual Steam Help.

Fred Rappuhn

I am presently working in a water pipe manufacturing plant. Spirally wound steel approx. 1/4" thick, welded ID/OD. These pipes are anywhere from 24" to 101" in diameter cut at 50" length, then lined with concrete approx. 1/2 - 3/4 thick. We cure the concrete under steam for 18 hours.
We wrap the ends with plastic and after the pipe sits for 4 hrs a steam hose is inserted into the plastic and a condensate drain at the bottom, steam is manually turned on for 18 hrs, timing needs to be precise or concrete will flake. Temp. is regulated with a probe inserted in plastic for a thermocouple . We could have 20 pipes on steam at any given time, some can be controlled manually but with only a first shift operation need auto on/off

QUESTION: Trying to set an auto steam on, steam off device, ie: time clock that would count off the 4 hours and turn on a zone valve for steam and shut off at 18 hrs. We have a electronic controls tech, but think this is down a steam boiler mans area.

Any thoughts I can take back to the controls tech. ???

Jamie Hall

How big a steam pipe are we talking here? One can get motorized valves in pretty much any size one wants, but the big ones start getting kind of pricey. But once you have the motorized valve, you can control it with any device you want, and the motors can be had in a range of voltages. One caution: if this is low pressure saturated steam, you really have to use a full port valve. Saturated steam does strange and wonderful things when it goes through a reduced port valve. Also, there should be a trapped condensate drain downstream from the valve.

EBEBRATT-Ed

As @Jamie Hall said automatic valves are available. You can get self contained valves that have there own temperature sensor, or use motorized valves or solenoid operated valve for smaller piping (caution with water hammer on those)

Need more information, steam load, control voltage, control type, on-of, two position or modulating control valves are available

Fred Rappuhn

Now your asking questions out of my realm, the steam is piped to an a central manifold and to branch tee's, through a full port ball valve into a 3/4 hi temp rubber hose, like a radiator hose. Steam enters the pipe under no pressure, I assume.

I will make some photographs of our set up and post tomorrow.
Thanks

Fred Rappuhn

We are steaming a pipe that could be 5' in diameter and 50' long , just with plastic on the ends held with bungee cords.

Will post photos tomorrow

EBEBRATT-Ed

Ok. I would use a steam rated two way motorized control valve 3/4" ips. I would use on-off control and you could get the actuator with 24 volt or 120 volt actuator depending on the controls you want to use.

Now here's the problem. when the control valve shuts the steam and condensate will back up in the steam line, I would think you may need a steam trap to get rid of the condensate but this depends on the piping arrangement.

You may want to arrange the controls for a manual start and automatic shut off but more information is needed and your pictures will help

Fred Rappuhn

Photos of our present set up, as you see steam is to turned on manually, would like to automate this

Jamie Hall

Snake pit! I'd just replace those existing ball valves with motorized ones and then control the motors with whatever you want -- time switches, thermostats, whatever suits your needs.