Reconstruction of PM 3 (of the wet part and drying part)

Reconstruction of the wet part and completion of the PM 3 drying part.
Aim of reconstruction: production of fancy papers, width 2 200 mm at substance of 20 – 80 g/m² with machine capacity growth to 2 800 kg/h on the reel at assumed max. operating speed up to 400 m/min.

Sign of contract: December 2007.
Term of dispatch: September 2008.
Term of start-up: October 2008.
Guarantee tests: November 2008.

Delivery specification:

1. Hydraulic headbox with round distributor

Outlet width:	2 350 mm
Inlet capacity:	5 000 – 15 000 l/min
Stock consistency in headbox:	0,5 – 1,5 % b.d.

2. Modification and completion of wire part

The whole wire part has been raised to 1600 mm above the basement rail and extended at the same time. Delivery of a new cantilever construction with anchoring on the drive side, incl. stands of breast roll tilting, new chests of the whole press part and incl. attendance bridges on the attendance and drive side. Delivery of new stands of suction roll and drawing roll tilting, the suction roll raised according to the new wire height. Use of existing dewatering elements (breast table, 4 pcs open water boxes, 2 pcs double suction boxes and 1 pc triple suction box), added 2 pcs single suction boxes and 2 pcs double suction boxes with bearing. The wire part was completed with a new wire shaker with independent drive for breast roll shaking, breast roll bearing has been kept.

Wire part parameters:

Design:	cantilever – shaken breast roll
Height of wire part:	1 600 mm
Wire width:	2 450 mm
Headbox width:	2 350 mm
Max. operating speed:	400 m/min
Construction speed:	450 m/min
Wire tension:	7,0 – 8,0 N/mm

3. Press part modification and completion

The original press part consisted of two continuous presses with hand paper web threading from the wire to the press part. The 1^st press was replaced with a press with a three-chamber pick-up roll diameter 850 mm, the existing top guiding elements were used. Delivery of the bearing construction for the 1^st press incl. construction for attachment the top guiding of the 1^st press felt. Control by means of the hydraulic rolls is from the new hydraulics panel.
The press roll of the 1^st press Ø 970 mm was completed with a double oscillating doctor, spraying pipe with fan-shaped water jets. Existing guiding rolls, stretching, automatic felt run regulation were used. A stationary shaker of guiding roll was added. A delivery of new collecting chests of press water under the upper felt washing, attendance bridges, necessary stands for press part equipment and equipment for roll replacement.
2^nd press – delivered new bearing construction with connection of the top bearer with the first press and using the existing press rolls with bearing, the existing bottom felt guiding was used and moved under the press within the assembly.

Press part design and parameters:

Design:	welded, screwed construction
Felt width:	2 400 mm
Dry matter after press part:	depending on the input stock 44 – 45 % b.d.
Machine coating:	highly-efficient dewatering press needled felts

4. Press part modification and completion

The original drying part consisted of 18 pcs drying cylinders diameter 1 250 mm, 1 pc Yankee cylinder Ø 2 500 mm and 2 pcs cooling rolls Ø 1 250 mm. Within the machine reconstruction the drying part was completed by 2 pcs drying cylinders in the front part and a new division of the first two sections was carried out. Further the cogged wheels on the drying cylinders were replaced with the gearboxes of the silent drive. In case of the Yankee cylinder the existing drive has remained.

5. Modification and hood completion of the drying part

The front tilting wall of the existing hood was moved in front of the completed drying cylinders, a hood of the same design as the existing one was completed above the drying cylinders – length approx. 1 600 mm.

6. Modification and completion of the steam-condensation system and heat-recovery system

The existing steam-condensation system was completed with a connection of 2 pcs drying cylinders. Delivery of 2 pcs blow cabinets with connection to the existing hot air distribution pipeline.

7. Modification of the multiple motor PM drive

Completion of 5 pcs main drive units and 1 pc drive unit of guiding rolls.

8. Modification of the vacuum system

9. Couch broke agitator

• for discontinuous pulping of wet broke; located under the press part and the 1^st press of the paper machine

Pulping capacity:	3,3 t/h
Operating consistency:	3 – 4 % b.d.
Stator:	bored – Ø 20 mm

10. Hydrostatic drive

Press part circuit:

Providing:

• delivery of pressure oil for control of wire breast roll tilting
• delivery of pressure oil for control of wire drawing roll tilting
• delivery of pressure oil for pick-up roll control
• delivery of pressure oil for control of bottom press roll of the 2^nd press

11. Pneumatic drive

Operating air pressure:	0,4 – 0,6 MPa
Filtration grade:	40 μm
Air (instrumental):	modified and bare of condensate, filtered to 40 μm
Oil concentration:	1 mg/m3