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Discharge pumps For polymers and pre-polymers

Discharge pumps

The sum of all benefits is efficiency. This makes Oerlikon Barmag pumps an ingenious investment.

Oerlikon Barmag has been building precision gear pumps since 1922 for the most varied of applications. For over 30 years, discharge pumps for polymerization and polycondensation plants have been part of the production program. During this time, the pumps were continually further developed and adapted to the respective process requirements in an optimal manner. Oerlikon Barmag discharge pumps are characterized by their high operating reliability and extreme durability.

Discharge pumps – Oerlikon Barmag

The most important process-technology benefits are: - low power consumption; - low temperature increase in the melt (âˆ†Ď„); - low shear of the melt in the bearing points; - excellent filling of the gears as a result of the optimal feeding section; - even heating as a result of optimally distributed heating channels.

Geometry optimization

Oerlikon Barmag pumps are convincing in the polymer and in the pre-polymer area, as a result of their optimized design.

Housing geometry In the case of very high viscosities the large inlet diameter and the wedgeshaped feeding channel guarantee 100% filling of the discharge pump. This is further supported by the large gear modulus. The compact construction permits good, uniform heating without the need for heating the side plates separately. By using materials with the same heat expansion coefficients, the clearances set during assembly therefore correspond to the conditions during operation.

Geometry of the gears In general, Oerlikon Barmag gear pumps are designed with straight gears, to ensure that the gears – free of axial forces – are able to perfectly center them-selves in the product chamber. The special design of the bottom of the tooth gaps avoids high compression pressures and pressure pulsations. When being discharged on the outlet side, the melt can completely and gently escape to the face-side relief channels. Furthermore, the selection of the optimum modulus provides efficient conveying of the melt.

Discharge pumps – Oerlikon Barmag

Pump design

Professional calculation programs based on many years of experience, provide an optimized process-technology design for the Oerlikon Barmag discharge pumps. In addition to calculating processtechnology variables such as power consumption and melt temperature increase, the flow conditions, in particular inside the bearings, can be simulated for various individual cases. This permits optimum pump designs for each application. Layout diagram of a 4,200 cc/rev. discharge pump

3-D model for the 8500 cc/rev. discharge pump

Discharge pumps – Oerlikon Barmag

Principle of lubrication system

Seal systems

Stuffing box seal The stuffing box seal is the most commonly used seal and is simpler than the mechanical seal. The compressed seal can be adjusted in the event of wear

and tear. Integrated into the stuffing box seal is a chamber filled with a sealing fluid. Therefore, the pump can be started up and operated vacuum-tight.

Stuffing box rings Buffer fluid Pressure springs


Thread seal The thread seal exclusively seals using the thermoplastic medium that is being processed. In the jacket’s reverse thread, the melt slowly rises in the

direction of the outlet and cools, hence sealing it from inside and simultaneously functioning as a lubricant. A seal against any vacuum in the pump interior is not possible.


POLYVAC Because it is inexpensive and highly impervious, the Oerlikon Barmag-developed POLYVAC is the perfect seal. As a result of the combination, this seal unites the benefits of the stuffing box seal and the thread seal.

Sealing bushing with reverse thread

Further benefits: - low-maintenance seal, also against vacuum; - adjustable leakage by separate cooling.

Cooling medium outlet Temperature measurement hole Buffer fluid inlet Buffer fluid chamber

Graphite packing ring Buffer fluid outlet Cooling medium inlet

Mechanical seal The mechanical seal with its gliding ring and counter ring, each directed to the melt and ambient side respectively, offers extremely good sealing properties and is the perfect solution for discharge

pumps for pre-polymers. The buffer fluid circulating between the counter rings is heated by a thermo-siphon system and kept under pressure so that melt does not exit, or air enter.

Rotating gliding ring

Counter ring

Buffer fluid inlet

Shaft jacket

Clamping ring Buffer fluid outlet

Counter ring Rotating gliding ring Drainage

Discharge pumps – Oerlikon Barmag

Oerlikon Barmag Zweigniederlassung der Oerlikon Textile GmbH & Co. KG Leverkuser Straße 65 P.O. Box 11 02 40 D-42862 Remscheid GERMANY Phone +49 21 91 67-0 Fax +49 21 91 67-12 04 Internet: e-mail: Saurer Inc. 8801 South Boulevard P.O. Box 70 46 Charlotte N.C. 28241 U.S.A. Phone +1 704 588 00 72 Fax +1 704 588 20 47

The information supplied in this brochure is for guidance only. We reserve the right to modify it at any time.

OBA 104 e / 7/2007 Studio 45 / Koch Subject to changes

Saurer Far East Ltd. Units 3806B-3807 38/F, Wu Chung House 213, Queen‘s Road East Wanchai, HONG KONG P.R.CHINA Phone +852 28 27 43 14 Fax +852 28 27 52 50 Saurer India Pvt. Ltd. 306-309, Dalamal Tower Nariman Point Mumbay 400 021 INDIA Phone +91 22 2850 813 Fax +91 22 2044 322


Discharge pumps For polymers and pre-polymers The sum of all benefits is efficiency. This makes Oerlikon Barmag pumps an ingenious investmen...


Discharge pumps For polymers and pre-polymers The sum of all benefits is efficiency. This makes Oerlikon Barmag pumps an ingenious investmen...