Re: Hot Vulcanizing Of 500 / 3 Belt

Posted on 26. Jul. 2006 - 08:21

that question would be best answered by your belt manufacturer. Each manufacturer has their own procedures for hot vulcanizing that are specific to their belting.

It is best to follow those for warranty purposes as well.

Gary Blenkhorn
President - Bulk Handlng Technology Inc.
Linkedin Profile:

Offering Conveyor Design Services, Conveyor Transfer Design Services and SolidWorks Design Services for equipment layouts.

Belt Splice

Posted on 4. Aug. 2006 - 12:25


Mr. Blenkhorn is correct, consult with your belt manufacturer. That said, some generalizaions.

Step length, the longer the better, providing you can get it in your splice press in one cure. Unless you have cold ends and are master splicer. Typically on that belt, an 8" minimum step length, 12" is better.

Preasure: 100psi mimimum. 125psi is better

Cure temp is typically 300 degrees F minimum.

Cure time will be a factor of temp and the manufacturer's compound.

Hope that helps.

Ron Marler

Legg Co. Inc.


Posted on 23. Aug. 2007 - 08:58


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(not verified)


Posted on 29. Dec. 2007 - 02:27


Just watched a PN500/3 (5 + 1.5) belt get spliced and hot vulcanised yesterday. It was all left up to the manufacturer regarding splice length, temperatur, pressing time & curing time, but for your information this is what they used:

400mm splice length (approx 100mm steps), pressure was 100psi (i think)

Cook at 150C for 25mins

As for Curing/setting time we were told it could pretty much be loaded about 15mins after they finished heating it (though we dont plan to run it for another few weeks)

This was done using a portable vulcanising unit as the conveyor was sitting on galleries aprox 30m in the air. The unit itself only had a 500mm width. The conveying distance is approx 70m, so longer runs may require longer splice lenghts, but the belt manufacturer should know what they are doing.

Re: Hot Vulcanizing Of 500 / 3 Belt

Posted on 28. Oct. 2008 - 04:50

Dear Irfan,

1. Ideally a step length of 200mm to be given. total splice area will be 400X belt width.

2.pressure required on the splicing area is > 8Kg/cm2. To get the pressure to be set on the guage, divide the splice area(in sq. cm) by the product of the No. of cylinders and cross sectional area of each cylinder and multiply this with 8.

3. Temperature normally set fro Vulcanising is 150C so that we get 145 C on the belt surface.

4.Duration for 6+3 belt should be around 25 minutes after reaching 150C. The belt should be cooled to around 70C before releasing the pressure on the joint area.



Re: Hot Vulcanizing Of 500 / 3 Belt

Posted on 28. Oct. 2008 - 07:37

We need to know the grade of the belt. The HR grade belt needs to be removed after 60 deg.Centigrade while cooling where as M24 could be removed at 80 deg.centigrade. The cooking time depends on the belt thickness. It is said that belt thickness in mm multiplied by 3 minutes.

Re: Hot Vulcanizing Of 500 / 3 Belt

Posted on 18. Dec. 2008 - 05:29

As stated by earlier respondents, the right way is to refer to the supplier of belt. The belt should be vulcanized strictly as per their instruction, i.e. preparation of belt ends for joints, vulcanizing solutions, temperature, pressure, etc. This is a sensitive issue and if vulcanized incorrectly, the belt will snap. It will have warranty issues.

If you are doing such vulcanizing regularly in your plant, then you may be taking the services of vulcanizing contractor. If you have confidence about their know-how, take chance and do the job. In case of any complication, belt supplier will simply refuse to involve in the matter.

If still there is difficulty, you may have the belt maintenance catalogue of other makes in your plant, and follow them. This will have a somewhat higher degree of risk, unless you are expert in the matter.

We had the practice that the belt supplier has to also supply the vulcanizing solutions of valid life and depute his engineer for supervisory services and be responsible for the work so done. If the joint is not made properly, even belt may run misaligned and other problem of more concern.

Ishwar G. Mulani

Author of book : Engineering Science and Application Design for Belt Conveyors

Author of book : Belt Feeder Design and Hopper Bin Silo

Tel. No. : 0091 (0)20 2587 1916

Email :

Patent Owned Plc Touch Screen Conveyor Belt Vulcanizer

Posted on 4. Mar. 2010 - 01:34

Made-in-Jiangsu Chenggong Machinery-China

New and updated conveyor belt vulcanizer/vulcanizing presses, completely automatical control cabinet. Details as following,

Technical Parameters:

1. Voltage: 220 V, 380 V, 440V, 550V, 660V; 50/60HZ; 2/3 PH.

2. Temperature: adjusting between 0 and 200 ;

3. Calefactive time (From normal temperature to 145 ):≤30 mins;

4. Vulcanization pressure: ≤ 2.0 Mpa;

5. Time for vulcanization and heat preservation should be adjusted according to belts’ rigidity;

6. The belt joint length is relied on putting together of the vulcanizing press;

7. Please confirm products’ models and mark the width of belts when ordering;

8. Spare electric pump users may make order if needed.

Technical Parameters

Technical Parameter: Rubber Conveyor Belt Vulcanizer, transportable, manual press, light weight, along with all accessories and tool kit, containing the following but not limited:

--5 /6 pairs of Cross Beams;

--Two Platens (Heating Plates);

--One Water Hydraulic Plate;

--Vulcanization pressure: 1.0-2.0Mpa;

--Vulcanization temperature: 145 ;

--Difference in surface temperature of vulcanized plate: ± 5 ;

--Calefactive time (at normal temperature to 145 ): ≤30 min;

--Output power of Electric Control Cabinet: ≤36 Kw;

--Temperature adjustment range: 0 to 200 ;

--Timing adjustment range: 0 to 99 min;

Email: phone:0086-510-86950888-8008

MB: 0086-150-5214-4343 Fax: 0086-510-86353259

Re: Hot Vulcanizing Of 500 / 3 Belt

Posted on 11. Mar. 2010 - 08:24


Please do not use this Forum simply as an advertising platform.

LSL Tekpro

Graham Spriggs
(not verified)


Posted on 28. Apr. 2010 - 08:39

Good afternoon,

Can you help me about this graph (attached), i want to now if the Tension (T1 and T2) in the conveyor belt was correctly calculated?.

Thanks and Regards,

Marcos Suarez


counterweight (JPG)

Re: Hot Vulcanizing Of 500 / 3 Belt

Posted on 28. Apr. 2010 - 10:09

Yes, T1 = T2 = W/2

as long as the counterweight pulley is freely rotating

Re: Hot Vulcanizing Of 500 / 3 Belt

Posted on 13. May. 2010 - 03:40

One more time...

Why not do it cold with SC 2000.

(Much less fuss and about 90% of splices here are done cold on fabric belts)

Hot not necessarily better


LSL Tekpro

Graham Spriggs

Re: Hot Vulcanizing Of 500 / 3 Belt

Posted on 10. Sep. 2006 - 07:43

Dear Mr. Irfan,

Please refer the thread "How to Splice Steel Cord Conveyor Belts?" in forum Belt Conveyor Technology, for information on this subject.


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 :

Tel.: 0091 (0)20 25882916