In general the first pulley and second pulley are on the same structure, so that the motion of this segment automatically add the same belt length in common zone between telescopic section 1 and telescopic section 2. This style of mounting is repeated among the successive pulleys. Thus, telescopic extension / retraction does not alter the total belt length.

It is very difficult to explain this in writing, but you can better understand from the arrangement of pulleys and imagining to pulleys shifting but total belt length remaining the same.

Hence take-up can be put on any one pulley which is convenient.

Regards,

Ishwar G Mulani.

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

Email : parimul@pn2.vsnl.net.in

Tel.: 0091 (0)20 5882916 ■

Could you please send me more details about

telescopic belt conveyor working system.

gearbox,hydromotor or chain systems?

thanx ■

Dear sir,

Take up can be given on return side belt whereever it will be convient. It neet not be regular gravity take up. Some sort of tentioning system is required. For one arm fix one hinge at one end. tentioning pulley can be fixed at centre of the of the arm and other end counter weight canbe fixed.

Tentioning system is must. Other wise belt will be loosened or stretched.

Regards.

K. OBI REDDY.

obireddy.hantek@gmail.com ■

Originally Posted by limkevin

I just came across a telescopic conveyor with 3 -4 sections. I am interested to know how to do tensioning of the belt in the telescopic conveyor when the sections retract.

Greetings and salutations,

More important in the scheme of things is what are you are you going to be handling with this squirt boom conveyor?

As Mr. I.G. Mulani and K. Obi Redi have explained so well the pulleys act a tensioner within

the conveyor belt length.

These belts are common in underground conveyor systems used in long wall mining for coal.

Not to muddy the cricket pitch further but think of how this belt works this way:

a high capacity cable crane has a huge sheave block to to do two things "lift a very heavy load and wind wire rope" this happens over many sheaves winding and rewinding as it is spooled through the block as the wire rope is wound through the sheave block. The Multiple sheaves create additional area for the wire rope to travel and grip and increase its carrying capacity.

The same principal is applied but horizontally where there is a live carriage that holds a magazine of live belting which extends and retracts as required by the system operator. The belt take up usually hydraulic can be thousands of feet away just doing its job responding to the load on the belt.

A differential hydraulic cylinder operates the same way but uses a chain carrier to move a sled back and forth over sets of end rollers/pulleys for what ever purpose-which in most cases is a drill head for roof bolting machine to drill holes for roof bolts in a mine or top head blast hole drill for a quarry or a water well drilling.

lzaharis ■

Originally Posted by limkevin

I just came across a telescopic conveyor with 3 -4 sections. I am interested to know how to do tensioning of the belt in the telescopic conveyor when the sections retract.

As the conveyor changes length it is reasonable to assume that the laden length changes in sympathy & so the ideal situation would be where the take up is also sensitive to this requirement: otherwise the extended length must be catered for & then maintained throughout the working range. Not the best.

Fortunately telescopic conveyors are usually located undeground where a winch, or similar, is a preferred take up system anyway. ■

Originally Posted by alibasar

Could you please send me more details about

telescopic belt conveyor working system.

gearbox,hydromotor or chain systems?

thanx

This link will give you all the information you require about telescopic conveyors. Hope this helps

UPDATE:

Link removed by moderator. ■

Originally Posted by stevenwang

A wide range of telescopic belt conveyors that are used for material handling purposes in various industries. Our range of conveyors are provided with an extendable arm that helps in reaching full length of a truck or container. Mobile in nature, these conveyors can be easily moved or shifted anywhere with minimum man power effort. Further, we also offer these conveyors in different dimensions and lengths to suit the applications needs of our clients.

The major objective in the forums is to exchange specialist knowledge in response to specific issues raised. The quoted post does not contribute to the forum topic in the slightest way. ■

Originally Posted by Neil Shuker

Attach a rough diagram of a typical telescopic boom conveyor showing the belt configuration for both extended and retracted conditions. No change in tension is needed.

Regards

Neil Shuker

Can somebody please explain where the structure supporting the carrying strand of the extended conveyor has shrunk to? ■

Sorry chaps but I forget to ask where the drive sits.

Lots of high tension pulleys are indicated in the sketch. ■

I suspect the drive pulley is the big one at the bottom.

For the idlers, I am used to seeing the arrangement described in figure 7 of the following:

http://www.freepatentsonline.com/6896123.pdf

Regards,

Lyle ■

Analysis of the extension is straight forward. Assume it to be the conveyor under evaluation at the length of the burdened section under study. Power and counterweight must so accomodate the given geometry. Typically, the counterweight or fixed take-up (TUP) value is already sized for the worst case. Lesser lengths, that do not need such TUP force can either be automatically adjusted, or left as is. ■

Originally Posted by Lyle Brown

I suspect the drive pulley is the big one at the bottom.

For the idlers, I am used to seeing the arrangement described in figure 7 of the following:

http://www.freepatentsonline.com/6896123.pdf

Regards,

Lyle

Thanks Lyle,

The invention is very elaborate, at least, and there are much simpler alternative shiploaders on the market. In the patent drawings and text there is no aknowlegement that the sag tension requirement fluctuates rather severely in sympathy with the idler pitch variations. Has such a machine been put into service and was there any tendency for flapping and off-tracking? ■

As well as faster loading and unloading, the most important benefit of the Telescopic belt conveyor is the improvement in ergonomic working conditions for operators. The belt extendable minimises the need for operators to carry products manually and places the drop-off or take-away point directly at the operator’s side, accessible on-demand by a simple joystick movement. ■