How to determine if the frequency of use of scaffolding is normal?
To determine whether the frequency of use of scaffolding is normal, it is necessary to conduct a comprehensive analysis based on its design purpose, usage scenario, load characteristics, and maintenance status. The core is to avoid premature aging of components due to excessive use or resource waste caused by long-term idle. The following is the specific method of judgment:
1、 Frequency reference based on design purpose
Construction scaffolding (such as building external scaffolding, formwork support)
Normal frequency: Used in stages according to the construction progress, such as gradually erecting the external frame as the floor rises, and dismantling it after the completion of the external wall construction (the single continuous use period is usually 3-12 months, depending on the building height); The formwork is used according to the concrete pouring batch, with a short single use cycle (1-4 weeks), but it may be frequently rotated within the same project (such as 1-2 times per week for standard layer construction).
Abnormal situation:
Overuse: Repeatedly dismantling and assembling the same frame more than 5 times in a short period of time (such as within 1 month) without checking the components may result in node wear and pin deformation.
Insufficient use: The frame has been idle for a long time after being erected (not put into use for more than 3 months), and has not been protected against rust, which can easily accelerate corrosion due to environmental erosion (such as moisture and dust).
Non construction scaffolding (such as stage stands, temporary stands)
Normal frequency: Intermittent use according to activity requirements, with a short single use cycle (1-7 days), and usually no more than 10 uses per year. After use, it needs to be disassembled, stored, and maintained.
Abnormal situation: Continuous use for more than one month (such as long-term use as a temporary facility), or frequent disassembly and assembly within a year (more than 20 times), may cause fatigue damage to the connection parts of the upright and horizontal bars.
2、 Frequency judgment based on load and operating conditions
Load compatibility
Normal frequency: The load used on the frame meets the design limit (such as the axial force of the pole of the buckle frame ≤ 200kN), and the load type (static load/dynamic load) is checked before each use to avoid long-term overload (such as long-term stacking of materials on the support frame).
Abnormal situation: Frequently used in overload scenarios (such as exceeding the design load by 1.2 times), even if the usage is not frequent, it belongs to "destructive use", and the inspection cycle needs to be shortened and the replacement needs evaluated.
Environmental adaptability
Normal frequency: Can be used at high frequencies in dry, non corrosive environments (such as indoor decoration); In humid, coastal (salt containing) or chemical areas, the frequency of use should be reduced (such as not exceeding 15 days per month), and rust removal and maintenance must be carried out after each use.
Abnormal situation: Continuous use in a highly corrosive environment for more than one month, or cumulative use for more than 30 days within a year without anti-corrosion treatment, belongs to "excessive exposure" and requires mandatory detection of the degree of corrosion.
3、 Reverse calculation based on the degree of component wear and tear
Wear inspection of key parts
The connection node between the upright pole and the horizontal pole: If there are cracks at the welding point of the circular disk of the buckle type scaffold, or if the pin is deformed after repeated insertion and removal (unable to self lock), it indicates that the frequency of use is too high or the operation is improper.
Verticality of the upright pole: If the bending deviation of the upright pole exceeds L/1000 (L is the length of the upright pole) after multiple uses, it may be caused by frequent disassembly or impact loads. It is necessary to evaluate whether the deformation is accelerated due to excessive use.
Base/Support: The threads of the adjustable base are severely worn (the adjustment range exceeds 50% of the design value), or the support steel plate is deformed, which may be caused by long-term high-frequency adjustment or excessive load-bearing.
Comparison of maintenance records
If the maintenance frequency of the same batch of frames (such as replacing pins, welding disks) exceeds 3 times per 100 pieces within one year, or the maintenance cost accounts for more than 20% of the original value, it indicates that the frequency of use exceeds the normal wear and tear range, and the usage plan needs to be adjusted or gradually replaced.
