Dear Mr. Serdar CAMDIBI,

I do not know about the standard defining the capacity testing procedure for conveyor.

However, this testing can be done based on following guidelines :

1) You have to see your purchase contract with your supplier. Anything mentioned about the capacity testing etc. in your contract will prevail.

2) The first step is to have a meeting with the representative of your supplier to fix date and time for testing and also testing modality.

3) Name of the people who will be conducting this test and who should be present during such test.

4) Method for taking the reading & creating record and joint signatures on the document.

5) General practice is to have testing period of either four hours or eight hours at a time etc. and also the number of days during which the testing is to be done. For a small conveyor a 4 hours test could be adequate. Such period will depend upon the daily operation of the plant (concerned section).

6) If supplier scope is only single conveyor and suppose you have decided to conduct the test for 4 hours then you have to make the necessary preparation to feed the conveyor for 4 hours as per agreed method. Also, the system ahead of the conveyor should be able to receive this material.

7) The checking for conveyor capacity is to be done appropriate to your equipment. In a regular belt conveying system, there are belt weighers. If your chain conveyor is located as a part of such system then you can make use of the reading of belt weighers. If all such facility is not there then people also do such testing in a crude manner that is the number of trucks arrived and their content weighment at weigh bridge etc.

I do not know about your total system, so I am not in a position to make more specific statement. However, I think the above information will enable you to plan and define your testing procedure. The complexity of such testing will depend upon the value of the equipment or plant. For a less value item obviously it will be very simple in nature but for a large value item / plant, the testing happens to be a major exercise, a project in weeks.

Regards,

Ishwar G Mulani.

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

Author of Book : Belt Feeder Design and Hopper Bin Silo

Advisor / Consultant for Bulk Material Handling System & Issues.

Email : parimul@pn2.vsnl.net.in

Tel.: 0091 (0)20 25882916 ■

If U are looking at acceptance tests, perhaps u should think a bit more globally.

U should refer to the contract and technical specificastions and drawings for the bakground and basis for test regime.

Ideas include.

emergency stop functions - actual function and also no spillage nor overfilling of transfer chute

start loaded test

restart from blocked chute test

test of all blocked chute and belt drift sensors

belt alignment / tracking checks

motor and gearbox running temps, amps etc.

abnomral noise, vibrations etc

noise levels eg fast belts

number of restarts per hour on motor

braking distance checks

demand power checks wrt design

actual capacity as per your post

For Capacity > U will need a belt scale for your tests, or U could use bulk density and draw down from a hopper of known volume.

U could also stop the belt loaded and measure 1m of material on the belt > calculate/estimate effective tonnage rate.

Hope this helps

Cheers

James ■

In my experience I have not come across any "standard" for acceptance trials.

" .. we want to force them to the maximum duration that we can do .. "

What was in the original contract? Are you trying to impose conditions retrospectively? You can't expect a contractor to do more than was specified.

If you wanted specific capacity checks it should have been stated in your contract document up front! ■

Two conditions set the capacity for supplier warranties:

1. Weigh scale totalizer reading for a set time of (say 8 hours) that has sufficient power to deliver 600 t/h x hours x 8 hours = 4800 tons totalized. Of course the product stream feed rate should be controlled within a set amount. Product bulk density and variation in product stream must be allowed within a noted tolerance so that there is no spillage and there is sufficent power without compromising belt , idlers, and structures during running, starting and stopping for all load and weather conditions.

2. Belt edge clearance, at design tonnage -- must be within established guidelines to control against spillage either at the load station, at the transition discharge, or at vertical or horizontal curve sections. The edge clearance should include an allowance for product containment against spillage and includes variations in mistracking from :

a) belt internal construction deviation,

b) splice alignment deviations,

c) load station off-center loading (can be controlled by modern chute design),

d) product roll-back on inclines and declines which results in spills

e) product lump size sensitive to loading turbulence after skirts

f) variations in bulk density

g) comment from others ................ ■

The specific point of my above comments is that sufficient operation time must pass to observe some reasonable level of variations which confirms that the design meets a standard against spillage. Most contractors must convey for 24 to 48 hours of continuous duty as the commisioning sign off.

The sign-off includes sufficient operating time to check mechanical and electrical equipment vibration, overheating, and other critical long term operational behaviors, as well as spillage given above. ■

In addition to above following factors are very important for various conveyor components

0.0 Conveyor belt

Maximum tension of the belt at full load during starting and steady state condition

and actual available factor of safety of the belt



2.0Motor

Motor actual power consumption at Maximum load and factor of safty available

Temperature rise

Vibration level

3.0Pulley

Actual deflection of pulley shaft at full load

Temperature rise of Pulley Bearings

Vibration level of pulley bearings



4.0Actual speed of the belt compared to design speed

5.0Gear box

Actual factor of safety of gear box based on actual power consumption

Temperature rise of gear box

Vibration level of gear box

6.0Suitability of take-up unit

To start the conveyor at various loads

Availability of belt for at least one splice joint





7.0Suitability of chute design for following

No off center loading

Material degradation

No Chocking

Liners are positioned at all wearing pates

8.0Belt cleaners

Effectiveness of belt cleaners

9.0Skirt board

Check proper functioning of skirt rubbers

Above points may be checked as per terms of agreement between supplier and clint

A R SINGH ■