How efficient is the water jet cutting machine to process the die cushion?

The efficiency of water jet cutting machine in processing the die cushion is not a fixed value, but is influenced by four core factors: material characteristics, processing technology parameters, equipment configuration and product complexity, which shows a "medium efficiency" level as a whole (compared with laser cutting, die cutting and other processes, it has more efficiency advantages in small and medium-sized batches and complex special-shaped parts scenes). The following is an analysis from three aspects: the core influencing factors of efficiency, the actual efficiency range and the efficiency optimization direction, so as to help judge its efficiency performance more accurately:

First, the core influencing factors: the key variables that determine efficiency

Knife die spring pads are mostly elastic materials such as rubber and polyurethane (thickness is 1-5mm, hardness is 50-90 Shore A), and the core contradiction of its processing efficiency lies in "balancing precision and speed"-elastic materials are easy to deform and rebound, and the quality needs to be controlled through parameter adjustment, which further affects the efficiency. The specific influencing factors are as follows:

The concrete influence of influencing factors on efficiency

Material characteristics-hardness: the higher the hardness (such as hard polyurethane with 90 Shore A), the lower the cutting speed (to avoid edge collapse) and the lower the efficiency by 10%-20%;

-Thickness: when the thickness is greater than 3 mm, it needs to be cut by layers (1-1.5mm each time), and the efficiency decreases linearly with the increase of thickness (for example, the efficiency of 5mm thick material is only 40%-50% of 1mm).

Machining accuracy requirements-general accuracy (tolerance ±0.1mm): cutting speed can reach 50-80 mm/min;

-High accuracy (tolerance ±0.03mm): it needs to be reduced to 30-50mm/min, and the efficiency will be reduced by 30%-40% (it needs to slow down to ensure the trajectory stability).

Product complexity-simple parts (such as rectangular outline+round hole): without frequent speed change, the efficiency can reach 80-100 mm/min;

-Complex parts (such as multi-arcs, narrow slits and dense positioning holes): the speed needs to be adjusted frequently (the arc is reduced to 20-40mm/min), and the efficiency is reduced by more than 50% (for example, the efficiency is only 20-30mm/min in the dense avoidance groove area of the die spring pad).

Equipment configuration-High-pressure pump power: 37kW high-pressure pump (pressure 250MPa) is 20%-30% more efficient than 22kW pump (pressure 180MPa) (it can increase cutting speed);

-Table type: multi-head cutting (2-4 cutting heads) is 1.5-3 times more efficient than single head (suitable for mass production);

-degree of automation: with automatic loading and unloading equipment, the manual refueling time can be reduced (5-10 minutes can be saved in single refueling, and the efficiency can be improved by 15%-20% in batch production).

Second, the actual efficiency range: the specific performance in different scenarios

Combined with the actual application data of the industry, according to the classification of "batch scale" and "product type", the efficiency of water jet cutting the die cushion can refer to the following range (taking the common 3mm thick polyurethane cushion as an example):

1. Small and medium-sized batch production (10-100 pieces)

Simple parts (such as 100mm×50mm rectangle with two φ3mm locating holes):

The cutting speed of a single head is 60-70mm/min, and the processing time of a single piece is about 1.5-2 minutes (including positioning, cutting and picking), and the total time for 100 pieces is about 3-4 hours (including fine adjustment of intermediate parameters and quality sampling).

Complex parts (such as special-shaped outer contour+8 positioning holes+4 avoidance grooves):

The cutting speed is 30-40mm/min, the processing time of a single piece is about 3-4 minutes, and the total time for 100 pieces is about 6-8 hours.

2. Mass production (500-1000 pieces)

Configuration optimization: multi-head cutting (2 cutting heads)+automatic loading and unloading, material pretreatment (typesetting in advance to maximize the use of plates and reduce waste).

Efficiency performance:

Simple parts: double hair force, the processing time of a single piece is reduced to 1-1.2 minutes, and the total time for 1000 pieces is about 20-24 hours (2 working days);

Complex parts: double hair force, the processing time of a single piece is reduced to 1.8-2.2 minutes, and the total time for 1000 pieces is about 35-40 hours (3 working days).

3. Compare with other processes (horizontal reference of efficiency)

Compared with the "laser cutting" and "die cutting" processes commonly used in knife die spring pads, the efficiency of water knife cutting is positioned as follows:

Process efficiency advantage scenario efficiency disadvantage scenario remarks (for elastic materials)

There is no thermal deformation in water jet cutting small batch, complex special-shaped parts and large batch of simple parts with thick materials (laser cutting is easy to cause material aging due to high temperature)

Laser cutting thin materials (< ＜2mm), simple materials with thickness (> ＞3mm) and high elastic materials are prone to "edge burning" (which affects the elasticity of the spring pad).

Die-cutting for ultra-large batch (> 10,000 pieces), small batch and complex pieces need to make molds (the cycle is 3-5 days, and the cost is high).

Third, the direction of efficiency optimization: practical strategies to improve machining speed

On the premise of ensuring the precision (tolerance within ±0.05mm) and quality (no burr and no deformation) of the die spring pad, the water jet cutting efficiency can be improved by the following methods:

1. Process parameter optimization (core)

Matching of pressure and speed: within the tolerance range of elastic materials, moderately increase the pressure (for example, the polyurethane elastic pad is increased from 180MPa to 220MPa) and simultaneously increase the cutting speed (from 50mm/min to 65mm/min), and the quality of the incision (no edge collapse and no rebound) needs to be verified by 1-2 pieces of trial cutting;

Path simplification: under the premise of not affecting the use, the sharp angle (< 30) is changed into a small arc (R0.5mm) to avoid the efficiency loss caused by deceleration;

Typesetting optimization: adopt "closely nested" typesetting (for example, arrange a plurality of bullet pads with a spacing of 0.5-1mm) to reduce the idle cutting time (the idle cutting speed is usually 200-300mm/min, which is fast but has no processing value, so it needs to be reduced as much as possible).

2. Equipment configuration upgrade (long-term)

Adding multi-head cutting system: for batch orders, double cutting heads can directly double the efficiency (it is necessary to ensure the synchronization accuracy of the two cutting heads ≤ 0.02 mm);

Upgrade the high-pressure pump: upgrade the 22kW low-pressure pump (max. 200MPa) to the 37kW high-pressure pump (max. 300MPa), which can increase the cutting speed by 25%-30% (especially suitable for thick materials);

Introduction of automatic loading and unloading: mechanical arm+silo is equipped to realize the full-automatic cycle of "cutting-picking-loading", reducing the time of manual intervention (15-20 minutes of refueling time can be saved per hour).

3. Simplification of material pretreatment and post-treatment

Pre-fixing of materials: bonding a plurality of thin elastic pads (e.g. 1mm thick, 5 stacked) with a special adhesive film in advance (to avoid displacement during cutting) to realize "multi-layer synchronous cutting" (the efficiency is improved by 3-4 times, and it is necessary to ensure that the pressure is enough to penetrate multi-layer materials);

Post-processing combination: after processing, the surface abrasive is uniformly purged with compressed air, and the size is detected in batches (instead of individual pieces) to reduce the post-processing time.

Summary: the "applicable scene" of water jet cutting efficiency

The efficiency of water jet cutting machine in processing the die cushion is the best in the scenes of small and medium batch, complex irregular and thick elastic materials (giving consideration to both efficiency and quality, without additional die cost), while in the scenes of large batch of simple parts, the efficiency is weaker than that of die cutting, but stronger than that of laser cutting (without thermal damage). In practical application, it needs to be comprehensively judged according to the order quantity, product complexity and accuracy requirements-if the order quantity is 50-500 pieces, including special-shaped holes/grooves, the water-jet cutting can usually be completed within 1-3 days, and the balance between efficiency and cost performance is the best; If the order quantity is more than 1000 pieces and the structure is simple, the combination of "water jet and die cutting" can be considered (water jet making samples and die cutting mass production).