Damping Systems for Rolling Stock
18Pages

Damping Systems For Rolling Stock Guidelines For Selection And Calculation Of Railway Dampers

1. Definition Of Damper Type 3 1.1 Technical Data Sheets 4 2. Definition Of Damper Attachments 6 3. Calculation Of Damper Length 12 3.1 Drawings Of Damper Length 13

1. Definition Of Damper Type For correct damper operation the definition for the installation position LATERAL or VERTICAL and the variations of these positions are very important. Maximum damping forces in rebound and compression and damper piston velocities are most important values. The choises of the damper type defined are: Primary damper Secondary damper

1.1 Technical Data Sheets Primary and secondary damper max. damping force, rebound [N] max. damping force, comp. [N] piston velocity [m/s] max. damping force, rebound [N] max. damping force, compr. [N] Secondary damper piston velocity [m/s] maximum static tensile load → without rebound stop [N] maximum angle to vertical → with mech. rebound stop [N] (eye mounting) → with mech. rebound stop [N] (stem mounting) diameter of dust shield D1 [mm] (damper with stroke < 400 mm) → standard design → screwed design diameter of outer tube D2 [mm] Non-symmetrical damping characteristics are also...

1.1 Technical Data Sheets Yaw damper and special dampers with continuous piston rod max. damping force, rebound [N] max. damping force, compr. [N] maximum angle to vertical see calc. of damper length (page 12) diameter of dust shield D1 [mm] (damper with stroke < 400 mm) → standard design → screwed design diameter of outer tube D2 [mm] Non-symmetrical damping characteristics are also available (except T60/42,5).

2. Definition Of Damper Attachments Other important damper items are the attachments. The attachment TYPE affects directly the function (stiffness) and endurance life (bending moment) of the damper. Attachment parameters to be defined: ➔ Type of attachment for example: loop-loop stem-stem stem-loop loop-stem Attachment types loop-stem and stem-stem are only available for vertical dampers. Maximum conical, axial and radial deflection Attachment load Cradial and Caxial (mostly max. damping force) Definition of attachment design (see pages 8 - 11) 001 rubber bearing with trunnion rubber...

Attachment type: loop-loop Attachment type: stem-stem Attachment type: stem-loop Attachment type: loop-stem Attachment type for lateral and yaw dampers: loop-loop Mark “UNTEN/BOTTOM” must face towards ground in assembled condition

Damper type Dimensions in [mm] Figures in bold are standard designs Max. angle movements are single loads (no overlay) Spring rates can vary depending on application Missing data available on request Deviations from standard mounts are available on request

Damper type Dimensions in [mm] Max. angle movements are single loads (no overlay) Spring rates can vary depending on application Missing data available on request Deviations from standard mounts are available on request

Damper type Dimensions in [mm] Figures in bold are standard designs Max. angle movements are single loads (no overlay) Spring rates can vary depending on application Missing data available on request Deviations from standard mounts are available on request

Damper type Dimensions in [mm] Missing data available on request Spring rates can vary depending on application Deviations from standard mounts are available on request Non-zinc plated parts are equipped with a protection cap

3. Calculation Of Damper Length In order to avoid metal to metal contact in rebound and compression, due to suspension and bogie tolerances, it is recommended to provide an extra stroke reserve of 10mm for both directions. Compressed Length (Lmin) = dead length (L-fix) + upper attachment (L1) + lower attachment (L2) + stroke (S) + mechanical rebound stop length (LA) optional (see technical data sheets). Extended length (Lmax) = compressed length (Lmin) + stroke (S) Attention: To calculate the compressed length of damper type with through piston rod the stroke has to be multiplied by 2. Dead...

3.1 Drawings Of Damper Length Mark “UNTEN/BOTTOM” must face towards ground in assembled condition

Paint ➔ Pre-treatment: zinc-phosphate Electrostatic painting with epoxy based 2K water based paint Coat thickness 30 - 50 µm Oven drying at ca. 110 °C Sand yellow Tarpaulin grey Platinum grey Brown beige Leaf green Iron grey Dusty grey Pure orange Olive green Basalt grey Agate grey Reseda green Slate grey Quartz grey Reed green Anthracite grey Yellow olive Black grey Grey brown Sapphire blue Squirrel grey Umbra grey Gentian blue Silver grey Concrete grey Graphite black Steele blue Signal grey Graphite grey Preferred colours in bold typefaces

Identification (roll stamp on dirt shield) ZF Sachs railway dampers are generally provided with the following data: ZF Sachs part number - Type (PistOn/P. Rod dia. x stroke) - Damping resistances [N] at test velocities [m/s] Production date: week/year [e.g. 3505] Roll stamp plus adhesive label (standard design) Riveted plate (special design)

ZF Sachs AG Railway Technology Bogestrasse 50 53783 Eitorf Germany Phone: +49 2243 12-383 Fax: +49 2243 12-280 rail.technology@zf.com Driveline and Chassis Technology

Questionnaire to be used in conjunction with GUIDELINES FOR DAMPER SELECTION AND CALCULATION ZF Sachs, Eitorf, Germany Dept.: DHR Phone: +49 2243 12-280 Fax: +49 2243 12-383 Address: Bogestrasse 50, 53783 Eitorf, Germany Company: Contact: Phone: Fax: End user/customer: Vehicle type: Bogie type: Damper type: primary/secondary/horizontal/vertical/yaw/ (Please underline applicable types Other, please state) Quantity of specified damper per bogie/vehicle: Total production volume: Service conditions: Minimum life: Static rebound load: Service temperatures: Extreme temperatures: Definition Damper...

ft^d SACHS to be used in conjunction with GUIDELINES FOR DAMPER Design detail/physical characteristics Damper length: _ mm min. _ mm max. (includes reserve □ Yes □ No) Max. diam. space envelope: _ mm Paint colour: _ RAL (Default RAL 9005 black if not stated) p degree, conical a degree, torsiona Upper mounting Angular deflection (normal service) Static deflection rate kN/mm radial Lower mounting Angular deflection (normal service): Static deflection rate: kN/mm radial Damper characteristics Test stroke: Rebound Compression State drawing or document numbers: