BN-S20 solid cbn turning surfacing rolls instead of grinding
Category：News
PublishedDate：2018-01-05
The rolls usually appear cracks and other defects because of long time use, when the manufacturers meet these problems, they will use surfacing technology and make the rolls to previous dimension, which is called Rolls Surfacing.
Rolls, as one of the most important component on the Roll Mills, the rolls quality decided directly the efficiency of the machine and the product quality. Rollers belong to consumer goods, the rolls quality also decide the consumer qty. When the rolls appear some defects, the manufacturers usually use surfacing technology to make sure the accuracy dimension, not only reduce the production costs, but also improve the efficiency, and save the energy.
The following will share you some notes before machining the surfacing rolls and how to machine?
1. Before rolls surfacing
(1) Clean the rolls surface: If the failure mode is cracks, we need to clean the cracks,
(2) Ultrasonic testing: check the roll defects whether affect the rolls quality, especially whether the crack were cleaned;
(3) Demagnetization of rolls: Reduce cooling rate of metal and heat affected zone during surfacing, reduce tendency to harden and reduce weld stress. Preheat temperature according to the roll material and welding material carbon content and alloy content to decide.
2. When Rolls Surfacing
We need to choose the surfacing methods depending on the rolls materials, specification and failure mode. For example, Welding electrode surfacing is suitable for small batch and irregular rolls surfacing. Electroslag surfacing is suitable for flat rolls surfacing.
3. After Rolls Surfacing
The rolls through surfacing need heat treatment to Eliminate welding stress, improve the rolls performance, and avoid producing the cracks. Then machining the rolls, and restore the rolls surface dimension and the roughness requirements.
To obtain the surface dimension and roughness have 2 methods: Grinding and Turning. With the development of the society and the cutting tools, we researched the new cutting tools materials to improve the efficiency. That is cubic boron nitride cutting tools which can be used for turning instead of grinding. One of the example is that BN-S20 Solid CBN Insert, which used non-metallic adhesive and ultra-thin grain, realized machining the surfacing rolls and improve the processing efficiency, lower the tool costs.
Halnn superhard, as the leader of superhard cutting tools, continuous to research new cutting tools materials to satisfy the customers, and already offer service for many different industries, such as aerospace, automotive and other heavy machine. For large scale rolls, we usually recommend Halnn BN-S20 solid cbn inserts, the roughness can reach Ra0.4. If it needs higher roughness, you’d better turning first, then grinding.
If you have any questions on turning surfacing rolls, please feel free to contact with us info@halnntools.com, skype:info@halnntools.com.