Very difficult. belt tension does affect your readings. and this is not what you say a constant value. even in horizontal conveyors. The longer it is the more un precise it gets.

If yow can isolate yourselves from the long sloped conveyor and buy a load center with its own short belt. or weigh before or after the sloped conveyor.

Good luck. Marco Flores ■

none ■

Be carefull.

belt scales in long slopped conveyors can work well in the first year .

Then , you have to account for stuck iddlers, , crusting and all kinds of real world factors, again the shortest the conveyor the best.

marco ■

1/4% scales are indeed possible, but I have to agree with Mr. Flores. Urea and any of the fertilizer products can be extremely hard on bearings and structures. You may want to consider the solid roll type idlers, and possibly a stainless steel scale carriage. ■

Dear Shi Ramesh Grandhe,

The belt weigher you are looking for is mostly possible. The generally used accuracy is 0.5%. However, accuracy of 0.25% is not uncommon.

You can install the belt weigher on 9-degree incline conveyor, if the said inclination is conveying the material without slippage.

The belt weigher accuracy is affected if it is installed in convex or concave curvature, because in this situation the belt tension and its variation will affect the load on weighing idler. The load on weighing idler should only be due to gravity for accurate measurement.

As mentioned by other respondents, you have to choose the material of construction immune to the chemical effect. The incrustation of material on weighing platform, idler etc. should be prevented and it should be regularly cleaned.

There are well known routine calibration methods. The manufacturer and supplier of belt weigher can provide you the required information. Present day electronic belt weighers have inbuilt auto-calibration system.

The load cell accuracy will be of much higher order (close to 0.1%). However, the accuracy we are referring to is for the belt weigher as a system. You can get better accuracy by longer weighing platform with more numbers of idlers on the platform.

Regards,

Ishwar G Mulani.

Author of Book : Engineering Science and Application Design for Belt Conveyors.

Advisor / Consultant for Bulk Material Handling System & Issues.

Email : parimul@pn2.vsnl.net.in

Tel.: 0091 (0)20 25882916 ■

Is it OK to know the volume? We supply a Volume Measure System with an accuracy of 0,25% in fine powders.

This system is free of maintenance, has no influence by the inclination, belt tension or what so ever.

Look at www.jh.nl, swith to English, look at Volume Measure System.

kind regards,

Jur Lommerts

Jansen & Heuning Bulk Handling Systems

www.jh.nl

tel: +31 50 3126 448 ■

Dear Mr Ramesh,

You want accuracy of belt scale as 0.25% of what?Is it on FSD or on rated capacity?Kindly let me know first.I faced many problems while purchasing the same.

I installed belt scale on 14 deg. inclined conveyor in TATA STEEL, Jamshedpur & it is giving accurate result.Accuracy also depends on the following factors:

1. Location of belt scale.

2. Trough angle.

3. Type of take-up.

4. Loading on conveyor. etc.....

In order to check the accuracy of belt scale, you need another Check Weighing system.I also installed the same in TATA STEEL.

I repeat that only writing 0.25% accuracy, will land you many problems.So please be care full.

Best Regards.

A.Banerjee ■

Kindly go through the below link

href="http://www.ktekcorp.com/dnn20/Default.aspx?tabid=67&productID=108" target="blank">http://www.ktekcorp.com/dnn20/Defaul...&productID=108

Its LM2D and a new model also for better accuracy.

Attachments

lm2d-0202-1%20datasheet (PDF)

■

You may find the following publication by The British Material Handling Board useful for assessing performance features.

'Guidelines for Specifying Weighfeeder Systems'

Contact me at lyn@ajax.co.uk

I would also say that it is important to have a good design of the flow route to the feed system of a continuous weighing system to secure a stable and reliable feed that delivers the product in as consistent a state of density as possible. The amount of care required depends to a large extent on the potential variablitiy of the bulk condition, so fine powders require special attention, but in general a system with a good feed arrangement makes the control radically easier. ■

Dear Sir,

Installation of belt scale in an inclined conveyoy & its accuracy 0.25% is bit a difficult. But now electronic part of the weighing system is improved & with some correction factor we can get an accuracy of 0.25% of FSD.

Regards.

A.Banerjee ■

Dear Sir,

It is possible to install a belt weigher under the circumstances u hv mentioned. We can achieve the accuracy of 0.25% by providing 4 Idler stations with 8 Load cells. The 2 preceeding & succeeding Idler stations need to be machined ones. The Idlers need to be maintained for corrosion free movement.

For further details you can contact us.

Thanks & regards

V.Sundar

Director

Newton weighing System Pvt Ltd,

A8 Rajdanga Nabapalli

Kolkata

Ph: 033 2442 9991

Mob: 09830425045

Email: newtonws@gmail.com ■

Dear Mr.G Ramesh,

it is possible to provide that accuracy with multy Idler belt scale. If drop test can be performed then it will be easy to assertain the accuracy.

You may send your details to us.

Thanks & regards

V.Sundar

newton weighing system Pvt Ltd, Kolkata

Email: newtonws@gmail.com ■