German zimmer Sommer coupling, zimmer Sommer model, zimmer Sommer price

zimmer Sommer coupling refers to a shaft whose operating speed is higher than the first critical speed and lower than the second critical speed. There are also shafts with speeds higher than the second critical speed. To reduce vibration, this type of shaft should be used when high operating speeds are required. A safety margin must be considered during design; generally, the operating speed is controlled to be >1.3 times the first critical speed, and<70% of the second critical speed. When accelerating a flexible shaft, it must reach and pass through the first critical speed. Due to the presence of various damping factors such as the surrounding medium, support bearings, and internal material friction, if the speed increases rapidly, the deflection of the shaft does not have time to reach its maximum before quickly exceeding the first critical speed, and the operation tends toward balance.

zimmer Sommer coupling introduction

It consists of two hubs and a thin-walled metal tube, connected together by welding or bonding. Although many other materials can be used, stainless steel and nickel are the most common materials for the metal tube. The nickel tube is produced by electrodeposition. This method first involves machining a solid mandrel into a corrugated shape, electroplating nickel onto the mandrel, and then chemically dissolving the mandrel to obtain the nickel bellows. This method allows control over the precision of the bellows wall thickness and can achieve thinner walls than bellows made by other methods. These thin-walled bellows give the coupling high sensitivity and rapid response, making it ideal for applications in extremely small and precise instruments.

zimmer Sommer coupling structure composition

The input end of the coupling structure features a clamping collar design, where clamping screws generate preload to rigidly connect the power input shaft to the clamping collar. The output end features a taper-lock design, where tightening screws preload a cone, causing the expansion sleeve to expand and fit with the inner bore of the power output shaft, connecting them as a single unit. The middle section features a bellows structure, with both ends of the bellows adhesively bonded to the input and output ends.

zimmer Sommer coupling troubleshooting

From the coupling structure, it is known that the coupling transmits power to the power output shaft (gearbox shaft) via a taper-lock expansion fit, and to the power input shaft via a clamping collar clamp. Power is transmitted between the clamping end and the expansion end of the coupling through the bellows, which are connected to the expansion end and the clamping collar via adhesive bonding. The fault location is at the clamping collar and the bellows. Two pre-deformation slots are machined radially into the clamping collar, with a slot width of approximately 2mm. On the side with the clamping screw, the slot is through in the diametrical direction but not fully open in the depth direction at the junction with the bellows, having a beveled cross-section; the other slot is not open radially, but its longitudinal junction with the bellows is also not fully open, with a beveled cross-section. During clamping, the clamping screws are tightened to the specified value using a torque wrench, eliminating the clearance between the hole and the shaft through the deformation of the clamping collar to achieve clamping. As seen from the cross-sectional view, due to the presence of the two pre-deformation slots, the cross-section at this location is weaker, and deformation mainly occurs at these slots. The cross-sectional area of the pre-deformation slot on the side with the clamping screw is the smallest, making this section the weakest. Permanent V-shaped deformation marks at its end indicate that the stress at this location during clamping is relatively high, exceeding the yield limit of super-hard aluminum. According to the stress distribution diagram, once the bevel gear box and the main gearbox are assembled and clamped, the stress value at the adhesive interface of the pre-deformation slot on the clamping screw side is 164Mpa, and the deformation magnitude is 0.027mm. During launcher operation, the coupling is subjected to alternating composite stresses, resulting in even greater stress and deformation at this location. If minor defects such as voids, inclusions, or flaws exist at the adhesive interface during manufacturing, micro-cracks will first form at defective areas within the region of maximum stress on the coupling's adhesive interface when the alternating stress exceeds the bonding strength, creating a fatigue source. Due to stress concentration at the crack tip, the crack gradually expands as the number of stress cycles increases and the duration of constant stress extends. As the crack propagates, the adhesive interface is gradually weakened, leading to fatigue failure when the crack reaches a certain size. The coupling functioned normally during initial tests, but as usage time extended, cracks gradually propagated, causing the coupling to fail even under low loads. The existence of stress at the adhesive joint is a potential hidden danger leading to failure. To avoid generating high stress when the coupling clamping collar is clamped, annular grooves are generally cut into the clamping collar for stress relief.

Weidou Intelligent Technology specializes in selling German zimmer Sommer rigid couplings, zimmer Sommer flexible couplings, zimmer Sommer safety couplings, zimmer Sommer universal joints, zimmer Sommer disc couplings, zimmer Sommer jaw couplings, zimmer Sommer flange couplings, zimmer Sommer cross-slide couplings, zimmer Sommer slider couplings, zimmer Sommer gear couplings, zimmer Sommer tire couplings, zimmer Sommer elastic couplings, zimmer Sommer bellows couplings, zimmer Sommer roller chain couplings, zimmer Sommer spring couplings, zimmer Sommer original German imports. Customers are welcome to inquire and order.