Load-bearing Capacity
Load-bearing capacity is an indication of the load that accessories such as buckles and rings can support without breaking under specified conditions.
Contents6 sections
Definition and Overview
The load capacity indicates the strength of the components, such as buckles, D- ring, slide adjuster, and snap hooks, against the force applied to them. The indicated value is an estimate of the strength of individual components and does not guarantee the weight that the entire product can safely support.
In actual use, factors such as the direction of the load, sudden impacts, repeated opening and closing and friction, and the strength of the seams and tapes will also have an impact. Therefore, load capacity is treated as one of the criteria for selecting accessories and is checked in accordance with the specifications of the finished product.
Materials and structure
Metal components include brass, stainless steel, iron, and die-cast zinc alloys, while resin components use materials such as polyacetal, nylon, and polypropylene. Strength varies depending not only on the material but also on the wall thickness, cross-sectional shape, structure of the moving parts, and molding and processing conditions.
Even parts that look the same can have weak points in terms of strength, such as the central bar, opening/closing mechanism, spring, and rotating parts. Metal parts are generally hard and durable, but it is necessary to check the surface treatment, corrosion resistance, and susceptibility to deformation as well.
How to express size
Buckle and ring sizes are generally expressed by the inner dimensions of the part through which the tape passes. For example, even if the standard size corresponds to the tape width, the thickness of the tape, the fold, and the seam allowance can make it difficult to thread, so check not only the width but also how well it fits through the actual tape.
The external dimensions of a component affect the design, stitching position, and potential interference with other accessories. Components with higher load-bearing capacities may be larger and heavier, so it's crucial to balance required strength with the appearance and comfort of the garment or bag.
- Internal dimensions: This refers to the width of the opening through which tape or belts are passed.
- Compatible tape width: This is the width of the tape intended for use.
- External dimensions: These are the width, length, and thickness of the entire component, and will affect the installation space.
Main applications
Checking load capacity is especially important for bag handles, shoulder straps, backpack adjustments, and belts that bear the weight of the contents. In clothing, it is also used for waist adjusters, detachable straps, and ring that serve both as decoration and bear weight.
The required strength differs between decorative applications for light clothing and applications for holding bags and outdoor equipment. We organize the maximum storage capacity and expected pulling direction for each applications, and design the components, tapes, and sewing specifications as a single integrated unit.
How to choose and points to note
When selecting a load-bearing capacity, allow for a margin of safety against the expected maximum load and check the load-bearing capacity indication conditions. In applications where force is concentrated on one side, such as diagonal pulling, impact from drops, or repeated loading, the results may differ from those obtained when applying force steadily in a single direction.
The tape is checked to ensure it fits snugly through the component, taking into account its internal dimensions and width, as well as its thickness. For the stitched areas, the tape's tensile strength, sewing thread, seam allowance, and reinforcement specifications such as bar tacks are also considered. Even if the component itself is made highly strong, surrounding areas may break first.
Metal parts are checked for rust, discoloration, and plating wear caused by sweat, moisture, washing, seawater, etc. For products requiring needle detection, the presence or absence of metal parts and their impact on the needle detection machine are reflected in the process, and specifications are confirmed in advance if needle detector compatible is required.
FAQ
If it has a high load capacity, can I use it for heavy bags as is?
The load capacity cannot be judged solely by the stated load capacity. If the strength of the tape, stitching, mounting points, or textile is insufficient, they will break before the components themselves. Also, the load increases with impact and repeated loading, so it is necessary to check the product in accordance with its intended use.
What criteria do you use to choose the standard size of a buckle?
Generally, the selection is based on the inner dimensions of the section through which the tape passes and the width of the tape to be used. However, it may be difficult to pass the tape through if it is thick or if it is folded and sewn. Assemble it with the actual tape and check that the adjustment and opening/closing are smooth.
Which has a better load-bearing capacity, metal or resin?
A uniform comparison based solely on the material is not possible. Strength varies depending on the shape, wall thickness, moving parts, and manufacturing method. Metal parts are sometimes used in applications requiring high rigidity, but weight, rust, and discoloration must also be considered, and the selection should be based on the indicated values of each part and the usage conditions.
