tranquility

The following discussion assumes structural steel with the following properties is used for the supporting structure:
 An ultimate strength (Sut) of 400 Mpa
S’f = 0.65 x Sut = 260 Mpa
Yield strength (Sy) of 300 Mpa
Fatigue limit (S’e) of 160 Mpa

Both the Screen Mount and the coil spring induced stresses are far below the fatigue limit and are therefore harmless to the supporting structure if the structure doesn't resonate.
G. v Eeden, Comparison of a Neidhart Suspension and a Coil Spring Suspension, 2001

An exercise was done where a theoretical SN curve was used to model the damage during start-up and stoppage. The results are compared in the table below.

G. v Eeden, Comparison of a Neidhart Suspension and a Coil Spring Suspension, 2001 says: “As is clearly shown, the coil spring caused significant more damage during stoppage than the Neidhart system. Although the Neidhart system showed more damage during start-up”, the total damage for a start-up and stoppage was more severe using coil spring suspension.

• Increased load capacity
• Fewer units required
• Lower dynamic stiffness in vertical plane
• Drastically lower dynamical stiffness in horizontal plane

• Elimination of side sways,Reduced amplitudes during deceleration.

• Terrific vibration isolation,Excellent operation,Noiseless operation.

• No operating costs during lifetime

• Most economical screen suspension over lifetime

• No down-time or lost production due to suspension failure

• No maintenance required on unit

• No breakages due to mechanical failure

• Operates effectively, even under extreme conditions 

• Reliable under overloaded conditions

• Resistant to dust, water, corrosion

• Allows for predictive maintenance

Sasol Synthetic Fuels produce’s fuel out of Coal
2 Plants each having :
14 Ripple Flow screen 8 x 20’ 10 tons
14 Low Flow screen 8 x 20’ 12 tons
The first plant change over to Neidhart Screen Mounts during 1989.

Average lifetime of Screen mounts were ± 5 years

Sasol Synthetic Fuels experienced the following :

No forced stoppages or replacements during the lifetime of the screen mounts
No labour cost and no down time
100 % Availability for continuous operations as far as screen mounts is concerned

Diamond ore drops 1.5m onto the scalper screen. Rocks like this are no exception. The screen mounts in this exact case were installed in 1991 and has been replaced once since then.