Sugar Cane Blanket thickness

R

Thread Starter

Ravindra

dear forum Members,

i want to measure the level in the cane carrier of the Suagr Industry.
I was tried with Ultrasonic , and the measurement is not correct due to fluctuations in the cane , and gaps.
Could any forum memebers suggest me that through beam or photo sensors , and how to connect to the DCS systems

thanks
mullapudir
 
Hello ravindra

Is this after the crusher or before? If you mean before, it is quite inaccurate. after the crusher it is better to take a weigh feeder information than a level.

ICON Technologies pvt ltd, Chennai
suresh
EMail: [email protected]
 
J

Jimmy Saldivias

Dear Mullapudir:
A member of this forum made the same question several months ago. I reccomend you to look for this link in the previous messages. I will tell
you what I remember from this. In the first place I would like to point out that we have developed this application last year, with success I mus add. Trying to measure the "level" of cane on the carrier is not they way to go.
You should "weight" the cane on the carrier. Why? Because the motors that chop the cane, will work harder as more "mass" of cane is coming. SO you need to measure mass, not volume. Volume is very variable in sugar cane. If the cane was cropped with a machine it will come pre-chopped, which means that a very small "height" of sugar, will have a very high "mass" as measured by the weight. On the other hand, if the cane was cut by hand, you will receive a very bulky amount which represents only a very small mass. This is something that an experienced operator of the conductor will tell you, and will be glad to explain why. It is one of the first "secrets" that you learn when trying to become an operator of this sector within a sugar company.
The way to go is weight.
In order to weight, you have 2 ways to go: either you cut the supports of the conductor and support the system on conventional load cells or you don't do that and only attach (using screws) the special microcells manufactured by kistler-morse within the US.
I personally reccomend the microcells. They cost the same as conventional loadcells, but have a signal with a maximum value of 700 milivolts, as
compared with a 15 milivolts signal from conventional loadcells. Also you don't have to stop production to install them. You just go under the conductor, drill a couple of holes, make the internal thread with manual tools, and screw the sensors. We have done this on very different situations without having to stop the production during the installation phase. After this, you will be able to measure the "real amount" of cane you are feeding to the process.
This signal can be converted easily to 4-20 mA using any available amplifier.
After this is done, you can integrate it to your control system.
One last advice: stop trying to measure height, you are wasting your time.
I hope this helps.
REgards
MBA Ing. Jimmy Saldivias
Gerente
TECSIM
Phone: 591-4-4523438
Fax: 591-4-4523413
http://tecsim.trading.net
 
Dear Mr. Jimmy Saldivi

i am absolutely aggreing with you. As we want to tip the cane bin to the cane carrier. As we want to tip it in automatic i have two options one i has to measure the level. I did not find any sensor to keep underneath of the tippler and which is quite unsafe for instrument.

After seeing your mail i am changing my attitude to measure the weight rather than measuring the thickness.

If the load on the carrier is more , definitely the preparatory devices will take more load. Unfortunately all the sugar factrories are working in the same , which the speeds of the carrier was working on the number one mill chute
height. It means that we are regulating of the sppeds of the carries. Because of the speed variations some time the thickness will be more and some times the thickness will be less. you are regulating the speeds of the carrier with
respect to mill 1 load.

here i was taken up a project , with loss in weighment alogorithm, and control will be placed at the tippler, and chute height mills increse the mill 1 speed up to predefined value rather than slowing down the carriers at the back end.

Volume is definitely variable, some times cane will come compact , and some times it will spillage. And we are using hand cut cane , the lengths are very irregular.

I am very happy to dicuss with you, and you have already catched the where the pin point is there.
Could you please give me the kistler-morse web address please.

What application you have done this kind of the load cell. For the Sugar Industry application. Please clarify for me.

i tried to open your web site , but i did not able to open. How ever i will send you the fax.

regards,

mullapudir
 
Dear Mr.Vince Dooley,

I have seen you are an active paticipant in this forum. You have given many replies to me. Are you working in Sugar Industry. Please give your e mail
address please.

I will share my ideas with you.

Regards

mullapudi ravindra
 
D

Donald Pittendrigh

Hi Mullapudir

What part of the machine are you trying to control, the transport of raw the
cane to the pulper?

Reg
D. Pittendrigh
 
V

Vince Dooley

In a competitive world we need to solve problems quickly and constantly improve. One of the best ways to do that is by networking with other people in the industry and in other industries. Over the years I have built up many contacts but this forum and others like it provide the fastest and most efficieint means to network with a wide variety of people from many industries. Most problems have been solved before. I work in the Alumina industry but I have found that there are many applications in other industries that can be adapted to ours.

Yes I do participate in this forum because I believe that to be effective and attract contributors we must be active and share information. It increases our chances of getting answers to our own questions.

I have never worked in the sugar industry but feel free to contact me direct. My e-mail address is [email protected]

Vince Dooley
 
Hello,
Mr. D. Pittendrigh
I woluld like to tip autoatically by using the cane carrier load or cane carrier leel as a basic sensing .

regards,
mullapudir
 
D

Donald Pittendrigh

Hi All

I am assuming you want to decide whether to tip cane onto the carrier belt if it is empty or has enough room to take the load. There are 2 problems, the weight of the cane is not reliable as it may be chopped and compact or in whole pieces and occupying a lot of space on the carrier. The level of the cane is erratic and so normal level measurement doesn't help either.

Using an optical sensor is unreliable as the nature of the tipped cane is that it is not evenly spread and the sensor sees through the gaps. It is a difficult thing to control and the plants where I have dealt with the sugar industry the cane is either tipped from road trucks by an operator, or by a wagon tippler where the operator adjusts the pushing speed of the tippler to adjust the flow rate to an appropriate level, but this of course is a manual operation.

I would try two things, you can measure the power the motor is using to move the cane carrier and this will give you an indication of the load. If the load is too high, then no tipping is allowed. I would measure the level using an instrument such as Ultrasonic or radar, looking from above the carrier, and I would put a very slow filter on the analog value to get an indication of the real load on the belt, slow filter should not be a problem as you cannot fill the carrier too quickly either.

Ideally what you want to do is deliver the correct mass flow rate to the primary cutter and so you should control the speed of the cane carrier based on the load that you measure at the primary cutter motor. If the load is to low you speed the belt up and vice versa, depending on the speed of the belt, you only allow a certain number of tips per minute onto the carrier.

Of course these ideas are based on the practical concept of a cane carrier such as I have seen, there is no guarantee that yours looks the same. Send me a picture and I can think about this a bit more, if neccessary I can contact some of the mills in my area, I live in a cane producing area so there are a few people around who may be able to help.

If you have a picture you can email me at [email protected] just take the blank spaces out of the email address first.

Regards
Donald Pittendrigh
 
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