Circlip with Force Limitation for Pump Flange Safety
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing clamping rings for flange connections, particularly in circulating pumps, are prone to sudden failure due to improper handling, leading to unsafe conditions when used by non-professionals, as they can be over-tightened, causing the clamping device to break and resulting in uncontrolled component detachment or leakage of hazardous substances.
Innovation Solution
A clamping ring design featuring a clamping force limiting mechanism, such as a screw head with an internal profile (e.g., hexagon socket) that restricts excessive torque, ensuring the clamping screw cannot be over-tightened, thereby preventing sudden breakage and incorporating a centering projection and seal for secure alignment and tightness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the clamping ring is designed with a standard screw-nut connection, then the clamping device can be easily assembled and disassembled, but it can be over-tightened beyond the specified torque causing the screw to break and the connection to fail
Solution Approach 1:
The screw head is designed with an internal profile (such as hexagon, Torx, or Phillips) that has a specific geometric configuration. This profile geometry limits the maximum torque that can be applied during tightening, as excessive torque causes the tool to slip or damage the profile rather than continuing to tighten. This changes the torque parameter from unbounded to bounded by the mechanical properties of the internal profile.
Solution Approach 2:
The internal profile design acts as a pre-designed safety mechanism that cushions against over-tightening before it can cause damage. The profile geometry is selected and dimensioned beforehand to provide a natural torque limit, preventing the screw from being tightened beyond safe limits and avoiding catastrophic failure of the clamping connection.
2Strength
If the ring sections are over-dimensioned to ensure strength, then the clamping device becomes the weakest link, but this provides a safety margin for proper installation
Solution Approach 1:
The internal profile geometry parameters (such as the width across flats for hexagon or the point-to-flat distance for Torx) are specifically selected to match the tool being used. This creates a controlled torque limit that is lower than the strength capacity of the over-dimensioned ring sections, ensuring that the screw fails safely before the ring sections do.
Data Source
Figure 1~2
Figure 3
Figure 4
AI summary
The locking collar structure (11) has an open ring portion (17) for retaining a motor case-side flange portion and a pump casing-side flange portion. The ends of the open ring portion are connected with a clamping apparatus. The ends of the ring portion are moved with respect to each other and are clamped by the integration of the flange portions through the clamping apparatus which is provided with a clamping force limiting element (27). An independent claim is included for a centrifugal pump aggregate.