Roving frame/simplex BUBT TXE

YMT-2

1. Roving Frame

2. Group Member Name ID Md. Shamim Hossain 16172107035 SHAHRUKH HOSSEN 13172107036 MD. MOSHIUR RAHMAN 16172107030 Mahmudul Hasan 16172107010 ADIBUL HASAN ADIB 16172107011 Barnali Halder 16172107028 Nishat Munny liza 16172107027 Rifa rafia 16172107048 Md. Nazrul Islam Khan 16172107029 MD. NAFIZUR RAHMAN 16172107031 Sydatunnessa 16172107038

3. Introduction The roving frame is the machine that comes after the draw frame in short -staple spinning system The input is the finisher draw frame sliver and output is the roving frame is called roving The roving frame is called by various names in the industry and these are simplex , speed frame etc.

4. Objectives of Roving Frame The main function of roving frame is the make roving from the sliver. To draft the sliver to reduce weight per unit length. Insertion of protective twist in order to hold the fine strand of sliver. To make conical or tapper shape of the bobbin. Wind the twisted roving on to the bobbin. Winding of roving into a package that can be transported, sorted, donned on ring spinning machine.

5. Parts of roving frame & Its Function

6. Creel Creel is used to guide the sliver. Creel portion is present above the can. Creel help the sliver on their way to the drafting arrangements without any disturbance

7. Guide roller Guide roller are used to guide the sliver.

8. Condenser Condenser are used to condensing/pressing the sliver. The purpose of condenser is to bring the fiber strand back together again.

9. Pressure arm Pressure arm is use to give pressure onto the material.

10. Cradle Cradle are used to give proper tension to the upper and bottom rollers. For proper guidance of material.

11. Spacer The main function of distance clip are to maintain sufficient distance between top and bottom aprons to attenuate the strand properly

12. Aprons They are made of leather or synthetic rubber. They are usually about 1mm thick. The upper aprons are short. The lower aprons are longer. They run over the guide bar, usually known as nose bar, to position close to the delivery roller. They are used to guide and transport fibers during drafting.

13. Rubber Cord Cord are made of synthetic rubber and are mounted on upper rollers.

14. Flyer The flyer insert twist; each flyer rotation create one turn in the roving. Twist per unit length of roving depend upon the delivery rate.

15. Types of flyer a .Spindle mounted flyer (It gets motion from spindle b . Top mounted flyer (It gets motions from top of the flyer) c. Closed flyer ( conven tional)

16. Spindle The spindle is steel rod of circular cross section with its dia reduce at the top. The slot in which the flyer pin is mounted. The diameter of spindle also reduce at the bottom and takes shape of tapered cone. Angle of tapered is 80-90 degree.

17. Presser Arm The arm has to guide the roving from the exit of the flyer leg to the package.

18. Operations Involved in Roving Frame:- Creeling . Drafting . Twisting. Laying. Winding . Building . Doffing .

19. Imparting Twist The flyer inserts twist. Each flyer rotation create one twist in roving Twist per unit length depends on the delivery rate of roller

20. Draft Arrangement Conventional roller drafting system: 4 over 4 without apron. Modern Roller drafting system: 3 over 3 drafting system with double apron (Lakshmi Rieter FS185P ) 4 over 4 drafting system with double apron ( SKF PK 1600)

21. Drafting Zone In double apron drafting system 3 over 3: Back Zone: Break draft is applicable in here. Amount of break draft is depends upon material.  Break draft affects on roving evenness Front zone : Maximum amount of draft is applicable in here. Apron is used in this zone.

22. Draft Zone

23. Winding Winding There are two principle of winding : 1.Bobbin leading principle 2.Flyer leading principle

24. Bobbin leading principle Bobbin speed is higher than. Used for short fiber .   Let , Front roller delivery= L inch/min Bobbin speed at any instant point of winding = NB rpm Spindle speed at any instant point of winding = NS rpm Bobbin dia at that point of winding = d So , bobbin circumference = d Winding on speed, Nw = (NB – NS) rpm Total winding length / minute = d (NB – NS) Therefore, L = d (NB – NS ) In this formula, L, & NS are constants. So, with the increase of bobbin dia , bobbin speed decreases.

25. Flyer leading principle For flyer leading, Winding on speed, Nw = ( NF – NB) rpm Total winding length / minute = d ( NF – NB) L = d (NB – NS)

26. Faults of Roving Frame Irregular Roving. Roving breakage . Sliver breakage. Roller lapping. Unequal tapering . Hard roving bobbin. Ridgy bobbin . Thick thin place. M/C Faults: Fluction of power Ununiform rotation of flyer Using of damaged flyer . Damage top roller Damage apron .

27. Conclusion The input of roving frame is silver that comes from draw frame section where only parallel of comber sliver. The roving section reduces the linear density of draw frame silver by drafting. After reducing the linear density the silver is transfer into roving (a thin form of rope). This is the first stage where the twist is inserted for making a yarn in a spinning mill. The output of this section is roving which is wind on a bobbin and this is suitable for the further process.