Anglicky v odborných předmětech "Support of teaching technical subjects in English “

1. Anglicky v odborných předmětech"Support ofteachingtechnicalsubjects in English“ Tutorial: Engineering technology Topic:Tubemanufacturing Prepared by: Ing. Elena Nová Projekt Anglicky v odborných předmětech, CZ.1.07/1.3.09/04.0002 je spolufinancován Evropským sociálním fondem a státním rozpočtem České republiky.

2. Tube manufacturing

3. Tube manufacturing Tubes / Pipes are produced from metallurgical semi-products as follows: • rolling • drawing • extrusion • welding Accordingly tubes are either seamless (smooth) or with seam (welded).

4. Tube manufacturing • Tube rolling • Tubes (seamless) are mostly produced by rolling. They are further divided to: • Hot rolled • Cold rolled • Manufacturing is divided into two operations: • 1. Production of hollow pressings, slabs or pierced semi-products • 2. Semi-products processing into tubes / pipes

5. Tube manufacturing • Billet manufacturing: • 1. Trepanning round semi-products by transversal rolling in piercing mill. • a) between two rolls with eccentric axes, b) two discs • A) B) • Transversal rolling – Mannesmann principle • Stiefel principle

6. Tube manufacturing • 2. For further diameter reduction is used so called PilgerMill • Sketch of pilger • mill: • Rolling is by two rolls turning in opposite directions on mandrel, thereby thinning tube wall and elongating the tube. Inner and outer diameters are conserved.

7. Tube manufacturing • 3.Final operations are calibration and cooling. • Pilger Mill

8. Tube manufacturing • Drawing of high precision tubes • Cold drawing is mostly done for pipes or tubes of small to medium sizes (from0,1 to250 mm), thin to thick walled. • For cold drawing is used ‘cold draw bench’. • Semi products are tubes made by cold rolling of length to 4.5 m.

9. Tube manufacturing • Die tube drawing - drawing power is transferred by tube, its inner diameter or wall thickness is not eliminated by any tool. • Drawing by clamped mandrel - drawing power is transferred by tube (final product)

10. Tube manufacturing • Manufacturing of welded tubes • Seamless tubes are expensive. Welded tubes are cheaper: • 1. Welding of strips heated in gas furnaces proceed through profile rolls twisting the strip. Next pair of rolls compress the tube and its edges butt welding them. Producing tubes up to 100mm diameter and 2 to 10mm wall thickness. • Production of tubes • with butt welding.

11. Tube manufacturing • Seam welding of tubes. • Short tubes with longitudinal seam are welded edges adjusted and welded. • Long tubes from strip or flat steel are bended at hold by pulley while welded. • Disk electrodes are hold down by great pressure, welding speed is 70 m/min. • Tubes of diameter 7 to 700 mm and wall thickness 1 to 20 mm are welded in this manner.

12. Translate:

13. Answer these questions: • Types of tube manufacturing? • Describe seamless tube manufacturing. Describe pilger mill • Explain tube cold drawing • Describe manufacturing of welded tubes

14. Used literature • http://www.ksp.tul.cz/cz/kpt/obsah/vyuka/skripta_tkp/sekce/04.htm • http://www.ksp.tul.cz/cz/kpt/obsah/vyuka/skripta_tkp/sekce/obsah_kovy.htm