To assist you,

EP VS NN is the difference in the warp and weft cords in the fabric make up of the belting. EP (E) Stands for Polyester and (P) Nylon, so the make up would be a Poly/Nylon construction. This construction is what I recommend to the majority of my customers! The Nylon gives the belt the ability to stretch if material becomes trapped between the belt and the pulleys as where a poly/poly fabric may just allow holes punched in the belt. At the same time the Poly limits the amount of stretch and re-splices required due to stretching.

NN fabric has a much higher rip and tear value due to the toughness of the Nylon fabric, but has problems with over stretching.

Hope this helps

Regards,

Troy DeWitt

tedewitt@cox.net ■

Originally Posted by tedewitt

To assist you,

EP VS NN is the difference in the warp and weft cords in the fabric make up of the belting. EP (E) Stands for Polyester and (P) Nylon, so the make up would be a Poly/Nylon construction. This construction is what I recommend to the majority of my customers! The Nylon gives the belt the ability to stretch if material becomes trapped between the belt and the pulleys as where a poly/poly fabric may just allow holes punched in the belt. At the same time the Poly limits the amount of stretch and re-splices required due to stretching.

NN fabric has a much higher rip and tear value due to the toughness of the Nylon fabric, but has problems with over stretching.

Hope this helps

Regards,

Troy DeWitt

tedewitt@cox.net

Dear Mr.Troy,

What I understand weft will be same Nylon in both the cases. Do we have any standard or measure their rip or tear values for comparison?

My EP belt supplier says that the elongation of his EP belt is kept slightly on higher limit so that it would allow the trapped materials.

Comments please!

Regards, ■

...........................

Do you have Comparison-Information about those two kinds of type, EP-belt VS NN-belt ?

Comparasion about their each belt-constructions, their each characteristics, and their each physical properties

..........................

My comments are as following:

1. Belt Construction: Mr. Troy Dwitt has given a very clear information, really appreciate.

2. Characteistics:

NN belt: Flexible, high tension, impact resistant, low elongation

EP belt: High modulus, low elongation,impact resistant, excellent heat resistant.

P.S.: Nowadays, EP belt is more popular than NN belts.

3.Physical properties: regarding as this point, they are similiar, they are all avaiable for the materials handling of heavy duty, high speed and medium distance.It depends on your favorite.

In a word, suitable is the best.

Merry Christmas and Happy New Year!

Warmly regards,

Ms. Molly

Qingdao Huaxia Rubber Industry Co., Ltd.

www.huaxiarubber.com

export@huaxiarubber.com

For more information, please visit:

https://edir.bulk-online.com/profile...r-industry.htm

http://www.google.com/search?client=...UTF-8&oe=UTF-8 ■

This is a very true statement

Originally Posted by tedewitt

NN fabric has a much higher rip and tear value due to the toughness of the Nylon fabric, but has problems with over stretching.

One of the biggest reasons we stay away from NN belting and only use EP is becasue of the greater elongation of a nylon/nylon carcass vs a polyester/nylon carcass.

We were mistakingly sold a N/N belt on a conveyor U/G that had limited vertical take-up travel. During start up under load the counter weight would hit the ground and then hit the conveyor frame running full take-up travel.

This problem went away when we installed a EP belt to replace it.

Just my own experience with the two. ■

Kind attn. : Mr. Irfan Eko B,

Regarding comparison between NN and EP belts, firstly the NN belt has polyamide material (symbol P) in warp as well as weft direction. The polyamide is a chemical name but it is commonly known as nylon. The EP belt has polyester in warp direction and polyamide (nylon) in weft direction.

Then the comparison is between the properties of nylon yarn and polyester yarn. Such comparison happens to be for elongation at break, change in tensile strength due to moisture etc.

Then comparison can be for carcass behaviour for elongation, effect of moisture, chemical effect, temperature effect, etc.

I suggest you to contact your belt supplier to provide the comparative values. It is difficult to put such details here.

One important advantage of EP belt is its less elongation under load and thereby lesser take-up stroke. The typical values for take-up stroke are 2.25% versus 2.75 or 3%. The EP belt has better load support characteristic. It requires somewhat bigger diameter of pulley, but this does not imply that you will have to change all the pulleys because often existing pulleys are oversized due to different reasons. If drive pulley changes then gear box ratio will also change.

Possibly EP belt is slightly more costly. The buyers tend to opt for EP belt where price is not the issue.

Regards,

Ishwar Mulani

Author book - Engineering Science and Appication Design for Belt Conveyors

Author book - Belt Feeder Design and Hopper Bin Silo

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

Email : parimul@pn2.vsnl.net.in ■

it's similar for EP belt and NN belt, the fabric composition is different as Troy DeWitt

said.

The main performance difference for the two stytle belt is:

EP belt have lower elongation comparing to NN belt.

that is because "The EP belt has polyester in warp direction and polyamide (nylon) in weft direction. "as Mr.Ishwar Mulani said.

The actual fact I know as a conveyor belt supplier is that:

EP belt is more popular than NN belt.

Partly may because of the performance.

As I know part of buyer ask NN belt not because of the belt performance of charactor,but because that the belt he or she want to replace is NN belt, that is similar case that some people ask cotton fabric conveyor belt.

Generally I suggest EP belt if there is no specific requirements about the belt performance.

Hope it is useful for Mr. Irfan Eko B and friends in the same industry.

Yours sincerely

Luke

Swall Belting Inc.

swall.belting@gmail.com ■

Dear sir,

We are Shuangma Rubber Manufacturing Limited, which is a leading manufacturer of rubber conveyor belt in China, we hope we can do some cooperation. Our products are,

1. Conveyor belt

Cotton conveyor belt, CC

Polyester conveyor belt, (EP)

Nylon Conveyor Belt, (N/N)

Chevron conveyor belt, (C5)

Oil Resistance Conveyor belt

Multi ply fire resistance Conveyor belt.

Endless belts

Referring to different standards as DIN, AS, BS, RMA, and ISO. Some other standards are also available.

2 .Rubber sheet / Rubber mat

CR, SBR, NBR, EPDM, NR, Silicone / horse mat, anti-fatigue mat, fine ribbed, wide ribbed, stud, etc. Skirtboard Rubber

All products are in high quality and competitive prices, which are mainly exported to

the USA, UK, Italy, Russia, Turkey, South Africa, Southeast Asia, Middle East and so on.

Any related items interested, pls contact me freely.

Contact Person: Jessica

E-Mail: : sales@hosebelt.com

Skyp: crystalbaobey

website: www.hosebelt.com

Tel: 86-0532-86660127 Fax: 86-0532-86660112

Dongying Developing district. Shandong,China ■

Hi irfan..

We put in Nylon warp and weft belts throughout one of our plants, and it turned out to be a big mistake.

The first thing as that in the mornings during commissioning, the counterweights were found on the ground, and we had to keep cutting out lengths of belt and re-splicing due to creep.

The second thing was the belts rolled into pipe shapes and didn't track well.

The supplier ended up replacing all of them with EP and all was then well.

On the next plant using EP I put a counterweight way up high. Next morning it was still way up high, and the client insisted that I splice in more belting as it simply stayed there when the conveyor wasn't running.

We only use EP or steelcord now

Cheers

LSL Tekpro ■

Nylon can also have low shrinkage if it is processed with a psuedo shrink agent. Better belt manufacturers know these agents. Some practice it on regular basis. ■

Originally Posted by Graham Spriggs

Hi irfan..

We put in Nylon warp and weft belts throughout one of our plants, and it turned out to be a big mistake.

The first thing as that in the mornings during commissioning, the counterweights were found on the ground, and we had to keep cutting out lengths of belt and re-splicing due to creep.

The second thing was the belts rolled into pipe shapes and didn't track well.

The supplier ended up replacing all of them with EP and all was then well.

On the next plant using EP I put a counterweight way up high. Next morning it was still way up high, and the client insisted that I splice in more belting as it simply stayed there when the conveyor wasn't running.

We only use EP or steelcord now

Cheers

LSL Tekpro

Dear Mr.Spriggs,

I always wanted to control the elongation of the belt as per my wish.

Before 4 years , when I replaced one of my conveyors, having 500 metres of endless length, I used 5 Tonnes chain block and gave full tension before making the spliced joint. I thought the conveyor will not elongate as I calculated the pulling force at the drive pulley was only 2.26 tonnes.

Still the belt elongated for about 3 metres. I am searching for this answer.

The following link may be related with this topic.

https://forum.bulk-online.com/showthread.php?t=15415

Thanks & regards, ■

Interesting Larry..

Easier to just use EP and ST though, I fancy..

Cheers

LSL Tekpro ■

Not Quite So Graham,

Nylon has properties that are more suited than polyester for some applications. There is also the cost, which can vary between the polymer groups.

I was only making the point that some manufacturers treat yarns with more respect and get better performance. Preshrink or not-preshink. High growth after manufacture or not.

Just because its called nylon, doesn't mean it has the same properties between suppliers. ■

Dear Experts,

Please explain about Aramids. I heard that is equivalent to steelcord.

Thanks & regards, ■

Indeed, there are some synthetic fabrics that are extremely strong.

For example, I saw on television last night that the stuff they make the tug ropes out of to pull container ships out of dock, are up to seven times as strong as steel.

This prompted the use of such materials in belting especially by the sea where steelcords are subjected to corrosion.

As far as I recall, the belts were OK, but the problems were in the splicing of such belts due to poor bonding.

Cheers

LSL Tekpro ■

First Aramids, measured be their strength-to-weight ratio are stronger than steel. Their achilles heal is they cannot tolerate compression nor can they tolerate hertzian contact with another aramid strand. They need to be coated with another polymer protective coating. They are too brittle.

Second, 7 times as strong as steel?? By what measure, stength-to-crossectional area? Tension, compression, shear, ????, Strength-to-weight ratio such as Kevlar??

As you know Graham, they splice Kevlar using the finger technique. Bonding is a problem for some aramids. Latest versions of Kevlar have overcome this difficulty, like with nylon, by special coating. Cutting can be a problem so that the local fibers are not seriosly damaged, if they must carry load. ■

Yep...!

They said up to seven times stronger than steel..

They were refering to the synthetic fibre they have developed in an attempt to make a fibre that is as strong as what spiders make their webs out of.

It is a twisted chain polymer of increadible strength. In addition, they have developed a new way to wind it into strands that in turn they twist into ropes up to about 5 or 6 inches diameter for the tugs.

They then had to develop a new way to splice the ropes to make the eyes at the ends that do justice to the incredible strength of the rope itself.

I think it was on satelite TV probably on National Geographic or possibly Discovery, on a programme about "really strong things"

Cheers

LSL Tekpro ■

Dear All,

According to the experience, the elongation of NN belt is larger than EP belt, and generally, it is aproved that max 4 percent elongation at the working tension.

About the price I am not sure of different market, but for certain producer, the cost is similar.

Best regards,

Luke

swall belting inc.

swall.belting@gmail.com ■

Originally Posted by nordell

Nylon can also have low shrinkage if it is processed with a psuedo shrink agent. Better belt manufacturers know these agents. Some practice it on regular basis.

This is absolutely wrong. The best belt manufacturers, like us, do not use shrink agents or any chemical treatment to reduce stretching. We use mechanical "pre-stretch" before and during curing.

However no one can reduce the permanent elongation of NN belting to the level of EP belting.

NN belting is an old fashion technology. May be used in some Southern states of the US...

Mr Nordell, when you don't know, don't speak or write. Please! ■

Learning! ■

I see I missed the Sempretrans comment:

I know of multiple manufacturers that treat the fabric with a process that limits latent shrink in its final construction. Since I am bound by confidentialities, I cannot divulge the details. It is sufficient for interested parties to ask the question of the suppliers, if they are willing to divulge these details.

Nylon, without treatment will elongate much further than with treatment. This not only changes the takeup requirement but also the splice long term dynamic strength. Please explain why, beyond denier configurations, there are large differences in Nylon elongation? ■

Another comment:

I do agree that mechanical extension is a must, and is most beneficial, as it aligns the fabric structure to more evenly distribute the internal tensions for all fibers.

There are many mfgrs. secrets of belt construction and their material properties. That is why performance, quality, and costs differ. ■

Originally Posted by B.Heckel

This is absolutely wrong. The best belt manufacturers, like us, do not use shrink agents or any chemical treatment to reduce stretching. We use mechanical "pre-stretch" before and during curing.

However no one can reduce the permanent elongation of NN belting to the level of EP belting.

NN belting is an old fashion technology. May be used in some Southern states of the US...

Mr Nordell, when you don't know, don't speak or write. Please!

I cannot speak for Mr. Nordell as to his confidential knowledge of a certain manufacturers' fabric treatment metods. However, based on my experience, fabric treatments typically occur during the RFL application stage. Being a proprietary process for most top level manufacturers, it is impossible to say Mr. Nordell is or wrong. The "pre-stretch" is a process that occurs in the RFL & laminating process as a means to increase other mechanical properties as well. I will agree that nylon cannot manipulated, mechanical or chemical, to meet the same low stretch characteristics of polyester. That is why most manufacturers will use polyester warp yarns in high tension applications (greater than 600 piw) where the chance of increased stretch is unacceptable.

I would not call NN "old fashioned". And to pidgeon-hole its use to the "Southern US States" is in error as well. Another well known manufacturer has used NN almost exclusively on lower tension belting throughout the US, Canada, Central & South America.

However, I am a staunch supporter of EP (poly/Nylon). The Poly warp yarns are lower stretch with high tensile yield & resists extended stretch. Typically the permanent stretch will work itself out after several weeks of service. Only dynamic stretch will remain (visible in the take up system upon start-up). Whereas nylon will continue to stretch under tension. Specific safety factors designed into these fabrics keep continual stretch manageable. With the Nylon weft yarns, you get excellent load support, impact resistance (very important in some applications), fastener holding, as flexibility in troughing, and resistance to damage to material entrapment.

Buddy Wilson

Applications Engineer / TSM - Southeast

Fenner Dunlop Americas ■

Dear Experts,

How long would take for the conveyors to get the elongation as mentioned in the 10% of the belt rating? Please assume that the conveyor is running for 24 hours / day and stopped and started at every one hour. What are the environmental conditions accelerate the belt elongation?

Thanks & regards, ■