vulcanizer ■

Dear Sir,

Today the only public known method to make a splice with a steel cord belt is a hot splice with a high quality vulcanizing press (the pressure must be the same on all the surface). Most of the customers are using a vulcanizing press with a hydraulic bag because it gives a guarantee that the pressure will be constant on all the surface dependless of the thickness tolerance of the material and of the bend of the press traverses.So be aware that you need a good press and not a standard press!

As a manufacturer of such presses (named "waterbag press") I must confess that the main disavantages are the investment level (the press, a crane and a truck if you have a wide belt etc.) and the difficulty to make the splice if the conditions are difficults (bad accessibility, bad weather, etc.).

In some cases it's not necessary that the lifetime of the splice must be very long. That's why some of our vulcanizers (like Tip Top or Nilos) had decided to try to make a splice with our Super-Screw fasteners. It's an elastic fastener made of reinforced rubber with high tensile fabrics and self taping screws for the installation on the belt. Of course you need a metal point for the installation through the steel cords and a screw driver with mimimum 30 N/m torque for the screws. Today the customers who already used it are reporting that it's a good solution for some months or maybe for one year (i.e. urgency repair); but today for maximum ST2000. The main advantage is that you can do it within few hours with no specific investments. You will see attached a new installed Super-Screw 100 on a belt ST1000. If you want more information about this specific solution please don't hesitate to contact me directly.

Best regards

Edgar Jakob

MLT GmbH

href="mailto:info@mlt-deutschland.com">info@mlt-deutschland.com

Attachments

super-screw 100 on st1000 (JPG)

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I want to give the information that we have installed last week a new Super-Screw 200 on a ST2500 belt in a lignite open cast mine. The belt width is 1,800 mm (71 in.) and the length is approx. 1 Km (0.62 miles). The belt speed is 6.5 m/s (21.3 ft/s). This belt is working all around the clock and the average capacity of the conveyor is 2,500 m3/h; so it's a typical steel cord belt application.

The installation was finished only after 4 hours instead of 24 hours when the own vulcanizers of the mine do a hot splice. The chalenge was a short down time in case of belt damage or of removing & changing of a belt conveyor but not a long life time (it's the first experience with ST2500). But now after 4 days of running without any problems I'm confident that the life time will be long enough to be a profitable solution.

href="https://forum.bulk-online.com/attachment.php?attachmentid=6452&d=1191787324" id="attachment6452" rel="Lightbox35823" target="blank">■

Dear Jacob,

Excellent work. I am sure this will engage more interest in your product.

I would be pleased to become a subscriber to you product. Could you please send some details on how we can become more informed.

Thank You. ■

Dear sir

I am working in now hindlco industries Ltd in (Gujarat India)at steel cord pipe conveyor.

I having experience is in this Field 14 years. 12years worked in N. L. C(Neyveli Lignite corporation) in Tamilnadu at India. I know very well steel cord&fabric hot&cold.

I did the make steel cord joint maximum 400 above,

sir in cease select me I assure you that i will work very sincerely

Thank you ■

Dear sir

I am working in now hindlco industries Ltd in (Gujarat India)at steel cord pipe conveyor.

I having experience is in this Field 14 years. 12years worked in N. L. C(Neyveli Lignite corporation) in Tamilnadu at India. I know very well steel cord&fabric hot&cold.

I did the make steel cord joint maximum 400 above,

sir in cease select me I assure you that i will work very sincerely

Thank you ■

Originally Posted by nordell

Dear Jacob,

Excellent work. I am sure this will engage more interest in your product.

I would be pleased to become a subscriber to you product. Could you please send some details on how we can become more informed.

Thank You.

I can definitely vouch for the usage, with a few note to exceptions.

I believe MLT yet to have claim Superscrew specific usage for ST belts, it is still intended for fabric belt use.

However, I am informed that there are already quite a few belts with successful installation of Superscrew on steelcord belt, including myself.

Superscrew is definitely a powerful tool to have in the splicers' arsenal. Take 2 of our case for example:

First scenario

- Our splicers arrived on-site for 2 x ST1400 x 1600BW (ship loading belts) splices to be carried as emergency basis.

Ship docking fees were stacking up as earlier already delayed over 100 hours due to belt snapped and failure after rejoint.

>arrive on site >checked compound made sure not past expiry date > pull the compound and seems very springy (perhaps not properly stored and may already not usable)

>site owner insist to carry on >splice carried out > splice failed as the compound bubble up upon releasing press

Superscrew SS125 installed in 4 hours for 2 joints. Initial plan was for the Superscrew to allow belt to run until all materials are unlaoded and later to carry out a re-joint.

However, checking remaining compound in-stock all same character, "springy" and not recommend to use. Our client placed order for compound and takes 4 weeks delivery.

Compound arrived 5 weeks later, and since the health of the Superscrew joint is still good, they took the time to plan to replace the joint which eventually replaced after 10 weeks.

The belt ran 3 more times in between.

Second scenario

- Our splicers arrived on-site for 2 x ST1400 x 1000BW Emergency splices. Using a discarded ST1200 to bridge, since counterweight slack is not enough to renew the joint.

The discarded ST1200 has been left at the scrap yard for over 2years and rubber is quite brittle. Client has 24hours till the stock runs out and potential kiln stoppage.

Earlier splicing group refused to carry out the splice upon arriving on site and finding out the bridge joint is a piece of reclaimed belt, because there was

no belt in stock and the decision was made out of desperation. This setback cut available time and upon our arrival were left with 8 hours till the kiln comes to a halt.

Superscrew SS180 installed in 4 hours for 2 joints. Initial plan was for the Superscrew to last for a week till limestone stock is healthy to carry out a re-joint.

Critically, Superscrew managed to held on to the brittle belt and by the time the splice is carried out, there is a gap on the edge of about an inch wide and 6 inch deep.

Superscrew, saving maintenance/production manager the blushes. ■

Originally Posted by Anthony.wwtechnic

I can definitely vouch for the usage, with a few note to exceptions.

I believe MLT yet to have claim Superscrew specific usage for ST belts, it is still intended for fabric belt use.

However, I am informed that there are already quite a few belts with successful installation of Superscrew on steelcord belt, including myself.

Superscrew is definitely a powerful tool to have in the splicers' arsenal. Take 2 of our case for example:

First scenario

- Our splicers arrived on-site for 2 x ST1400 x 1600BW (ship loading belts) splices to be carried as emergency basis.

Ship docking fees were stacking up as earlier already delayed over 100 hours due to belt snapped and failure after rejoint.

>arrive on site >checked compound made sure not past expiry date > pull the compound and seems very springy (perhaps not properly stored and may already not usable)

>site owner insist to carry on >splice carried out > splice failed as the compound bubble up upon releasing press

Superscrew SS125 installed in 4 hours for 2 joints. Initial plan was for the Superscrew to allow belt to run until all materials are unlaoded and later to carry out a re-joint.

However, checking remaining compound in-stock all same character, "springy" and not recommend to use. Our client placed order for compound and takes 4 weeks delivery.

Compound arrived 5 weeks later, and since the health of the Superscrew joint is still good, they took the time to plan to replace the joint which eventually replaced after 10 weeks.

The belt ran 3 more times in between.

Second scenario

- Our splicers arrived on-site for 2 x ST1400 x 1000BW Emergency splices. Using a discarded ST1200 to bridge, since counterweight slack is not enough to renew the joint.

The discarded ST1200 has been left at the scrap yard for over 2years and rubber is quite brittle. Client has 24hours till the stock runs out and potential kiln stoppage.

Earlier splicing group refused to carry out the splice upon arriving on site and finding out the bridge joint is a piece of reclaimed belt, because there was

no belt in stock and the decision was made out of desperation. This setback cut available time and upon our arrival were left with 8 hours till the kiln comes to a halt.

Superscrew SS180 installed in 4 hours for 2 joints. Initial plan was for the Superscrew to last for a week till limestone stock is healthy to carry out a re-joint.

Critically, Superscrew managed to held on to the brittle belt and by the time the splice is carried out, there is a gap on the edge of about an inch wide and 6 inch deep.

Superscrew, saving maintenance/production manager the blushes.

Please send a brochure and technical details of the product for our information and action.

Narayanan Nalinakshan.

Consultant in Material Handling,

E mail.nnalinb@gmail.com ■

Vinh Phuc:

Steel cord belts should be spliced using the vulcanized method. You should follow the splice pattern designed by the belt manufacturer. Also, ensure that you use belt manufacturer approved material and a vulcanizer with sufficient pressure and size.

Without spefic belt rating information, it is imposssible to give you guidance - other than checking with the belt supplier/manufacturer.

Regards, ■

Hi,

we can send you full steelcord splicing method for any type and spec. Just drop me a line to my e-mail (stan.holcroft@fennerdunlop.com).

We can also offer a new type of kit. It is a preformed kit with all the grooves already made in the bottom cover, thus allowing a quicker jointing time and a lower skill requirement in making the joints. This should allow the joint to last quite a long time longer than other types of joint.

My company is a major manufacturer and can offer a quote on the blet too if required.

Kindest regards,

Stan Holcroft ■

Dear Mr. Phuc,

The steel cord belt or any belt should generally be vulcanised strictly as per the guidelines given by the belt manufacturer or the supplier. They also provide the information about the various materials, solutions, vulcanizing procedure, heating temperature, heating duration, pressure, etc. to be used in such vulcanizing process. This will avoid the contractual liability complications.

For general information, you can study the various / available literature of the different makes.

You are at vulcanizing stage, which implies you have already procured the belt from some source. So specific option is to refer to the supplier, in addition to the information you get from this forum.

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 ■

Some rules-of-thumb:

1. Step length of oppositing cables passing each other should be no less than 100 times the cable diameter. Preferably, the multiple should be greater than 125 times.

2. Rubber gap between cables in the splice should be greater than 2 mm.

3. Rubber gap between calbes should be greater than .35 tiimes the cable diameter for cables less than 7 mm and .25 times the cable diameter for cables large than 10 mm.

4. Cable butt ends should have a spacing of 50 mm.

5. Cable bend zones beyond the step sections should be greater than 20 times the cable diameter

6. Step pattern varies with cable diameter. The cable diameter should be selected based on the splice pattern and belt strength. Often, this is not done because belt mfgrs keep standard cable diameters which lead to suboptimization of the belt design.

7. Smaller cables equate to lower cost belts. However, beware that too many cables can make construction difficult and can lead to a lower dynamic strength efficiency due to the poor quality of the splice.

8. Belt safety factors are selected based on country of origin. Some mfgrs have performed dynamic fatigue testing to qualify the belt safety factor at 5.5:1 or less. Those that have not should not be qualified for a safety factor below SF= 6.7:1. There are many belts operating below SF 5.5:1 today. ■