181 洗碗机内胆与喷淋件
洗碗机内部的工况
洗碗机内部是高温高湿 + 洗涤剂 + 水压的组合。洗涤水温 50-75℃，高温程序可达 80℃，洗涤剂是碱性（pH 10-12），喷淋压力 0.5-1.5 bar。
这三个条件叠加，对塑料件是严峻考验。内胆主体走不锈钢，是因为塑料在这个环境里长期可靠性还不过关。
喷淋臂是核心塑料件
喷淋臂要在 70℃ 热水中长期旋转喷射，走 PA66-GF30 耐水解或 PPS。
普通 PA66 在碱性热水里会水解，两年强度下降 40%，喷淋臂变形后喷淋角度就偏了，洗不干净。
耐水解 PA66 加碳二亚胺抗水解剂，在同样条件下强度保持 88%。
现场还原：喷淋臂上的白垢
2025 年 3 月，佛山一家洗碗机厂的实验室里，测试工程师给我们看一台服役两年的样机：喷淋臂装拆下来，臂体表面一层白垢，中央喷嘴孔缘有轻微变形，水流偏了。
工程师解释工况的时候，我们把几个数记下来了：洗涤水温 60-70℃，强洗程序到 75℃；洗涤剂是强碱性，pH 在 11 上下；每天两次程序，按十年寿命算一万多次循环。
喷淋臂在这种工况里泡着转一万次——高温、强碱、机械冲击（碗碟碰撞）、水垢沉积，四样一起来。
原喷淋臂用的通用 PA66，问题是三样：强碱环境下酰胺键水解加速、玻纤裸露后藏垢、喷嘴孔缘被水垢磨偏。
我们给的方案分两层：料换耐碱水解改性 PA66（主链稳定化加低析出配方），结构上喷嘴孔缘加硬（局部矿物填充）。两年验证跑下来，白垢减半，喷嘴偏移消除。
洗碗机这个产品，国内渗透率在爬坡，工况验证的账还没多少人算透——欧洲市场把它当十年家电做，国内的喷淋臂还在按「能用就行」选料，这条差距就是改性供应商的窗口。
水泵与滤网
排水泵和循环泵的叶轮、泵壳走 PA66-GF30 耐水解，要耐磨（水中含残渣）+ 耐温 + 耐水解。
滤网走 PA66 或 PP，要耐温 + 易清洁。这一块的失效表现是堵塞和漏水，是洗碗机售后投诉的主要来源之一。
碗篮滑轨与滚轮
碗篮要反复拉出推入，滑轨和滚轮是磨损件。滚轮走 POM 或 PA66 耐磨改性，滑轨走 PA66-GF30。
关键是要自润滑——洗碗机内部不能加润滑脂，会被水冲走。
自润滑 PA66 加 PTFE，摩擦系数 0.18，推拉寿命 3 万次以上。
深一层：强碱是尼龙的另一个天敌
聊家电用 PA，大家先想到热水，其实洗碗机里的碱和热水一样致命，值得把机理讲清楚。
尼龙的分子主链是酰胺键，水解就是水分子把酰胺键剪断。酸性环境和碱性环境都催化这个反应，但碱性条件下的水解更麻烦：碱催化水解是不可逆的，链一断就断了，分子量往下走，材料发脆。
70℃ 强碱水溶液里，普通 PA66 的分子量衰减速度是常温水里的几十倍。
工程上的应对有几条路：一是换键——共聚改性或用半芳香族体系，让水解位点更稳定；二是压低水分渗透——矿物填充提高结晶度，让水进得慢一点；
三是低析出配方——碱环境里普通配方的助剂会析出，析出物又加速表面降解，低析出体系的表面稳定性好一档。
还有一条常被忽略：餐具洗涤剂这几年碱性越来越强（去油需求），同型号洗碗机换个洗涤剂配方，塑料件的寿命预期就变了。整机厂的验证要按「最恶劣洗涤剂假设」走，别按标配洗涤剂——消费者不会按说明书用的，这是家电材料验证的铁律。
碱和热这两关都过了的 PA 改性牌，才是洗碗机件的正解——只过一关的，报价再便宜也撑不到十年。
碱性环境下的材料选择
洗涤剂是碱性的，pH 10-12 对 PA66 有侵蚀——酰胺键在碱性条件下水解更快。
PP 和 PPS 耐碱性远优于 PA66，所以洗碗机里很多件走 PP。
但 PP 耐温和强度不够，所以受力件还是 PA66，非受力件走 PP——这是洗碗机选料的基本分界。
噪音是隐性竞争点
洗碗机的噪音水平是重要的产品竞争力，高端机做到 42 dB 以下。
塑料件对噪音的贡献有两处：一是水泵叶轮的动平衡，塑料件的尺寸精度和吸水变形会影响平衡；二是喷淋臂的旋转摩擦。
这两处都要在选材和公差上控制，PA 吸湿变形是噪音的隐形推手。
工程实测：4 条强制测试
测试1：碱性水解。pH 11 热水 1000 h，耐水解 PA66 强度保持 88%，普通 PA66 降至 60%。
测试2：耐碱性对比。PP 在 pH 12 环境强度保持 95%，PA66 保持 70%——非受力件走 PP。
测试3：自润滑寿命。PTFE 改性 PA66 推拉 3 万次无异常，纯 PA66 在 1 万次卡滞。
测试4：吸湿变形。PA66 叶轮吸湿后动平衡偏差 0.3 g，噪音上升 4 dB——要控制吸湿。
追问三连：采购最常问的三件事
一问：喷淋臂走 PA 还是 PP。 主流分野：入门机型 PP 加矿物填充（便宜、耐碱、但刚性和耐温低），中高端走 PA66 改性牌（刚性、耐温、耐磨都强）。判断线看两点：水温 70℃ 以上 PP 吃力，喷淋臂带轴承位和复杂结构的走 PA。两条线不是高低之分，是成本档位之分。
二问：水泵叶轮和喷淋臂能同料吗。 大部分能，但水泵叶轮多一个动平衡要求——叶轮转速高，料批间的密度一致性直接影响振动。同牌号没问题，跨牌号混用要复测动平衡，这个细节翻过车的厂不少。
三问：碗篮滑轨轮的耐磨怎么验。 滑轨轮是洗碗机里「轻载高频」的典型：负载不高，但一万次开合是起步线。验证做往复滑动一万次加碱水浸泡组合，磨耗量按十年不卡顿设阈值。POM 和耐磨 PA 都能做，碱环境里 PA 要用耐碱牌，POM 耐碱好但刚性低，看结构取舍。### 算一笔材料账：洗碗机的十年售后曲线
洗碗机的材料账要按十年售后曲线算，这个行业的产品寿命预期正在从五年向十年迁移，曲线的差异就是市场分化的差异。
以喷淋臂为例：耐碱水解专用牌比通用 PA66 贵 4 元，单机差价占整机成本不到 0.3%。通用料在第五年上下的白垢、变形、喷偏投诉率，行业均值在 3% 到 5%；专用牌按欧洲市场的数据能压到 0.5% 以下。
一台洗碗机的十年周期里，4 元的差价换来的是售后率差 3 个点。按单台售后成本 150 元算，3 个点的售后率差就是 4.5 元的期望成本——材料差价当期就打平，还没算十年里的两次口碑溢价（复购和转介绍）。
洗碗机在国内还在渗透率爬坡期，第一批用户的好评决定品类的成长速度，这个阶段「售后率」的口碑权重比任何时期都高。
对整机厂的建议是把喷淋臂、滑轨轮、滤网三件的售后数据单列追踪——这三件是洗碗机的「材料三高中」，哪件的售后曲线陡，哪件的材料档就该升。数据驱动到这个颗粒度，材料预算才会花在刀刃上。### 边界声明
| 工况 | 推荐材料 |
|---|
| 喷淋臂 | PA66-GF30 耐水解 |
| 水泵叶轮 | PA66-GF30 耐水解耐磨 |
| 滤网与非受力件 | PP |
| 碗篮滚轮 | POM 或自润滑 PA66 |
| 滑轨 | PA66-GF30 + PTFE |
工程备忘
洗碗机塑料件量产前必须做碱性水解 + 高温强度 + 推拉寿命三项。受力件走耐水解 PA66，非受力件走 PP。
实战案例：常见踩坑与正解
踩坑一：按常温物性表给洗碗机件选料，没考虑长期工作温度。家电件长期在 60-90℃ 下工作，常温强度再高也会热老化失效。正解：拿热老化后的数据选料，PA66 在 80℃ 长期工作要选耐热氧老化牌号。踩坑二：为了降本把增强料换成未增强料，或者把 GF30 降到 GF15。洗碗机件的玻纤含量是算出来的，不是拍出来的。正解：降玻纤含量必须重算蠕变和强度，不能凭经验。踩坑三：噪音和异响问题最后才查，发现是塑料件摩擦或松动。正解：家电的噪音投诉占比很高，塑料件的配合公差和自润滑要在设计阶段就定。
反向案例：三年就没声音的滚轮
2024 年，华东某品牌洗碗机售后数据里有一条曲线不正常：开合异响投诉从第三年开始陡增，第四年占比到售后问题的 15%。拆机看：碗篮滑轨滚轮磨成多边形，滑轨面也被磨出沟。
那批滚轮用的是普通 POM，没做耐磨强化，也没做滑轨配套硬度设计。POM 本身耐磨不差，但这个工况里有两个变量：碱水长期浸泡让 POM 表面微溶胀，磨耗加速；滑轨金属面硬度和滚轮不匹配，磨滚轮也磨轨。
整改方案：滚轮换耐磨改性 POM（含硅油润滑体系），滑轨表面处理加硬。售后曲线第二年就回到正常水平。
这家厂的品质总监复盘时说的很直白：滚轮单件成本两块钱，换耐磨牌贵五毛；三年前的降本省了几毛钱，三年后售后翻倍——洗碗机是长寿命家电，售后账本的折现期比谁的预期都长。
家电件的降本决策，凡是「三年后见分晓」的位置，都值得把售后返修的期望成本乘进去再拍板。这个算法简单，难的在于有没有人愿意在降本会上把它算出来。### 延伸判断：最容易被漏掉的隐性变量
洗碗机件的量产事故里，有一半不是料选错了，是隐性变量没控住。
第一个变量是含水率。PA 系材料出厂含水率、干燥条件、注塑前的存放时间，三者共同决定实际含水率，含水率不对，强度和外观都会变。
第二个变量是模具温度。模温低 20℃，表面浮纤和熔接痕强度可能差一倍。
第三个变量是装配后的时间。装完 24 h 和装完 30 天的扭矩、尺寸、密封压缩量都不一样。
这三个变量都不写在物性表上，但都写在失效报告里。
把这三件事写成一张表发给供应商，比打十通电话有用——洗碗机件的选型沟通成本，基本都花在这几项反复确认上。
补记：三个现场判断信号
信号一：喷淋臂水流偏移、孔缘变形。 水垢磨蚀加孔缘软化，先查洗涤硬度设置，料的问题看孔缘有没有白化——白化是碱水解进行时。
信号二：滚轮磨出棱、滑轨起沟。 配对硬度不匹配，换耐磨牌加滑轨加硬，两头一起改，只改一头还是磨。
信号三：内胆焊缝渗水。 内胆多为不锈钢，渗水多在密封件——查密封圈压缩永久变形和耐碱数据，材料这一环最便宜也最容易被漏验。### 验证顺序：三步走完再下单
第一步，定工况：水温、洗涤剂碱性、循环次数三样按「最恶劣用户假设」取值。
第二步，验耐碱：高温碱水浸泡加机械磨损组合测试，只泡不动或只动不泡都会高估寿命。
第三步，验售后件：喷淋臂、滚轮、滤网的十年售后曲线追踪制度建立起来，让数据回头指导材料档位。三步走完，洗碗机的十年承诺才有材料根基。
结语
料有人卖，判断不一定有人给——选料这件事，越早问越省事。
这类件的选料与试模，可以一起聊。
181 Dishwasher Inner Tub and Spray Components
Operating conditions inside the dishwasher
The inside of the dishwasher is a combination of high temperature, high humidity, detergent, and water pressure. The washing water temperature is 50-75°C, and the high-temperature program can reach 80°C. The detergent is alkaline (pH 10-12), and the spray pressure is 0.5-1.5 bar.
The combination of these three conditions is a severe test for plastic parts. The inner liner is made of stainless steel because plastic does not yet have long-term reliability in this environment.
The spray arm is a core plastic part
The spray arm needs to rotate and spray in 70℃ hot water for a long time, so use PA66-GF30 hydrolysis-resistant or PPS.
Ordinary PA66 will hydrolyze in alkaline hot water, and its strength drops by 40% over two years. After the spray arm deforms, the spray angle becomes off, and it cannot clean properly.
Hydrolysis-resistant PA66 added with carbodiimide anti-hydrolysis agent retains 88% strength under the same conditions.
On-site restoration: white scale on the spray arm
In March 2025, in the laboratory of a dishwasher factory in Foshan, a test engineer showed us a prototype that had been in service for two years: after removing the spray arm, there was a layer of white scale on its surface, the edges of the central nozzle were slightly deformed, and the water flow was off.
When the engineer explained the operating conditions, we noted down a few numbers: the washing water temperature is 60-70℃, the intensive wash program reaches 75℃; the detergent is strongly alkaline, with a pH around 11; the program runs twice a day, amounting to more than ten thousand cycles over a ten-year lifespan.
The spray arm rotates ten thousand times in this working condition—high temperature, strong alkali, mechanical impact (dishes clashing), and limescale deposition, all happening together.
The original spray arm used general-purpose PA66, and there are three problems: amide bond hydrolysis is accelerated in a strong alkaline environment, dirt accumulates after the glass fibers are exposed, and the nozzle hole edges are worn and deformed by scale.
The solution we provided is divided into two layers: changing the material to alkali-resistant hydrolysis-modified PA66 (main chain stabilization with a low-exudation formulation), and reinforcing the nozzle hole rim structurally (localized mineral filling). After two years of validation tests, scale formation was reduced by half, and nozzle offset was eliminated.
For the dishwasher product, the domestic penetration rate is climbing, but not many people have thoroughly calculated the operational verification accounts yet — the European market treats it as a ten-year home appliance, while domestic spray arms are still made with the mindset of 'as long as it works'; this gap represents a window for modifier suppliers.
Water Pump and Filter Screen
The impellers and pump casings of the drainage pump and circulation pump are made of PA66-GF30 hydrolysis-resistant material, resistant to wear (with residuals in water), resistant to temperature, and resistant to hydrolysis.
The filter screen uses PA66 or PP, needs to be heat-resistant and easy to clean. The failure in this area manifests as clogging and leaking, which is one of the main sources of dishwasher after-sales complaints.
Basket slide rails and rollers
The basket needs to be repeatedly pulled out and pushed in, and the slide rails and rollers are wear parts. The rollers use wear-resistant modified POM or PA66, and the slide rails use PA66-GF30.
The key is to lubricate yourself — you can't add grease inside the dishwasher, it will be washed away by water.
Self-lubricating PA66 with PTFE, friction coefficient 0.18, push-pull lifespan over 30,000 cycles.
Deeper: Strong alkalis are another nemesis of nylon
When talking about home appliances using PA, everyone first thinks of hot water. In fact, the alkali in dishwashers is just as deadly as hot water, and it's worth explaining the mechanism clearly.
The main chain of nylon molecules is composed of amide bonds, and hydrolysis is the process in which water molecules break these amide bonds. Both acidic and alkaline environments catalyze this reaction, but hydrolysis under alkaline conditions is more troublesome: base-catalyzed hydrolysis is irreversible; once the chain breaks, it breaks, the molecular weight decreases, and the material becomes brittle.
In a 70℃ strong alkaline aqueous solution, the molecular weight degradation rate of ordinary PA66 is tens of times faster than in water at room temperature.
There are several approaches in engineering: first, change the key — copolymer modification or use of a semi-aromatic system to make hydrolysis sites more stable; second, reduce water penetration — mineral filling increases crystallinity, slowing down water ingress;
Third is the low-precipitation formulation — in an alkaline environment, the additives in ordinary formulations will precipitate, and the precipitates further accelerate surface degradation. The low-precipitation system has a higher level of surface stability.
There is one more often overlooked point: in recent years, the alkali level of dishwashing detergents has been increasing (to meet grease removal needs). Even if you use the same model of dishwasher but change the detergent formula, the expected lifespan of plastic components will change. The manufacturer’s validation must be based on the 'worst-case detergent scenario,' not on the standard detergent—consumers won't follow the instructions. This is an iron rule in appliance material validation.
Only the PA-modified grades that have passed both the alkali and heat tests are the correct choice for dishwasher components — those that have only passed one test, no matter how cheap the price, won't last ten years.
Material selection in an alkaline environment
Detergents are alkaline, with a pH of 10-12, which corrodes PA66 — amide bonds hydrolyze faster under alkaline conditions.
PP and PPS have much better alkali resistance than PA66, so many items in the dishwasher are made of PP.
But PP does not have enough temperature resistance and strength, so the load-bearing parts are still made of PA66, while the non-load-bearing parts use PP—this is the basic division of material selection for dishwashers.
Noise is a hidden competitive point
The noise level of a dishwasher is an important product competitiveness factor, with high-end models achieving below 42 dB.
Plastic parts contribute to noise in two ways: first, the dynamic balance of the water pump impeller, where the dimensional accuracy and water absorption deformation of plastic parts affect the balance; second, the rotational friction of the spray arm.
Both of these places need to be controlled in terms of material selection and tolerance, as PA moisture absorption deformation is an invisible driver of noise.
Engineering Test: 4 Mandatory Tests
Test 1: Alkaline hydrolysis. pH 11 hot water for 1000 hours, hydrolysis-resistant PA66 retains 88% of its strength, while ordinary PA66 drops to 60%.
Test 2: Alkali resistance comparison. PP retains 95% strength in a pH 12 environment, PA66 retains 70%—use PP for non-load-bearing parts.
Test 3: Self-lubricating lifespan. PTFE-modified PA66 withstood 30,000 push-pull cycles without abnormalities, while pure PA66 stuck after 10,000 cycles.
Test 4: Moisture absorption deformation. After moisture absorption, the PA66 impeller has a dynamic balance deviation of 0.3 g and an increase in noise of 4 dB — moisture absorption needs to be controlled.
Three Consecutive Follow-up Questions: The Three Most Common Questions in Procurement
Question: Should the spray arm use PA or PP? Main differentiation: Entry-level models use mineral-filled PP (cheap, alkali-resistant, but low rigidity and temperature resistance), while mid-to-high-end models use modified PA66 grades (strong rigidity, temperature resistance, and wear resistance). Two points to judge: PP struggles with water temperatures above 70°C, and spray arms with bearing positions and complex structures use PA. These two options are not about better or worse; they are about different cost levels.
Second question: Can pump impellers and spray arms use the same material? Most of the time they can, but pump impellers have an additional dynamic balance requirement—the impeller rotates at high speed, and the density consistency between batches directly affects vibration. It’s fine with the same brand, but if mixed across brands, dynamic balance needs to be re-tested. Many factories have overlooked this detail and made mistakes.
Three questions: How to test the wear resistance of bowl basket slide wheels. Slide wheels are a typical 'light-load high-frequency' component in dishwashers: the load is not high, but 10,000 cycles of opening and closing is the starting point. The verification involves performing 10,000 reciprocating sliding motions combined with an alkaline soak, and setting the wear threshold according to a standard of no jamming for ten years. Both POM and wear-resistant PA can be used; in an alkaline environment, PA requires an alkali-resistant grade, while POM has good alkali resistance but low rigidity, so a structural trade-off is needed. ### Doing a material cost calculation: the ten-year after-sales curve of a dishwasher.
The materials account for dishwashers should be calculated according to a ten-year after-sales curve. The expected product lifespan in this industry is moving from five years to ten years, and the difference in the curve represents the difference in market differentiation.
Taking the spray arm as an example: the alkaline-hydrolysis-resistant specialized grade costs 4 yuan more than the general PA66, and the price difference per unit accounts for less than 0.3% of the total machine cost. The complaint rate for limescale, deformation, and spraying deviation of the general material around the fifth year is 3% to 5% on average in the industry; according to European market data, the specialized grade can reduce it to below 0.5%.
In the ten-year cycle of a dishwasher, a 4 yuan price difference results in a 3-point difference in after-sales rate. Assuming an after-sales cost of 150 yuan per unit, a 3-point difference in after-sales rate amounts to an expected cost of 4.5 yuan — the material cost difference is recovered immediately, not to mention the two instances of reputation premium over ten years (repeat purchases and referrals).
Dishwashers are still in the penetration growth stage in China. The positive reviews from the first batch of users determine the speed of the category's growth, and at this stage, the reputation based on the "after-sales rate" carries more weight than at any other time.
The suggestion to the complete machine manufacturers is to separately track the after-sales data for the spray arms, slide rail wheels, and filters—these three are the "three major materials" of the dishwasher. Whichever of these has a steep after-sales curve, the material grade for that component should be upgraded. Only when data is driven to this level of granularity will the material budget be spent where it really matters.### Boundary Statement
| Operating condition | Recommended materials |
|---|
| Spray arm | PA66-GF30 Hydrolysis Resistant |
| Pump Impeller | PA66-GF30 Hydrolysis Resistant and Wear Resistant |
| Filter Screen and Non-Load-Bearing Parts | PP |
| Basket Wheel | POM or self-lubricating PA66 |
| slide rail | PA66-GF30 PTFE |
Engineering Memo
Plastic parts of the dishwasher must undergo three tests before mass production: alkaline hydrolysis, high-temperature strength, and push-pull lifespan. Stress-bearing parts use hydrolysis-resistant PA66, while non-stress-bearing parts use PP.
Practical Case Study: Common Pitfalls and Correct Solutions
Pitfall 1: Selecting materials for dishwasher parts based on room temperature property tables without considering long-term operating temperatures. Appliance parts work long-term at 60-90°C, and no matter how high the strength at room temperature is, they will fail due to thermal aging. Correct approach: use data after thermal aging for material selection. For PA66 working long-term at 80°C, choose a grade resistant to heat and oxidative aging.
Pitfall 2: Reducing costs by replacing reinforced materials with unreinforced ones, or reducing GF30 to GF15. The glass fiber content of dishwasher parts is calculated, not guessed. Correct approach: if glass fiber content is reduced, creep and strength must be recalculated; it cannot be done based on experience.
Pitfall 3: Investigating noise and abnormal sounds only at the end, discovering that plastic parts are rubbing or loose. Correct approach: noise complaints make up a high proportion in appliances, so the fit tolerances and self-lubrication of plastic parts must be determined during the design stage.
Reverse case: a scroll wheel that hasn’t made a sound in three years
In 2024, there was an abnormal curve in the after-sales data of a certain dishwasher brand in East China: complaints about unusual noises when opening and closing surged starting from the third year, and by the fourth year, they accounted for 15% of after-sales issues. Upon disassembly: the rollers on the dish rack slide rails were worn into polygons, and grooves were worn into the rail surfaces.
That batch of rollers uses ordinary POM, without wear-resistant reinforcement, and without hardness design matching the slide rail. POM itself is not bad in wear resistance, but there are two variables in this operating condition: long-term immersion in alkaline water causes slight surface swelling of POM, accelerating wear; the hardness of the metal slide rail does not match the rollers, grinding both the rollers and the rails.
Rectification plan: Replace the rollers with wear-resistant modified POM (including silicone oil lubrication system), and harden the surface treatment of the guide rail. The after-sales curve returns to normal levels in the second year.
The quality director of this factory spoke very frankly during the review: the unit cost of the roller is two yuan, and switching to a wear-resistant brand costs fifty cents more; cost reductions from three years ago saved a few cents, but three years later the after-sales doubled—dishwashers are long-lived appliances, and the discounting period of the after-sales ledger is longer than anyone's expectation.
For cost reduction decisions on home appliance components, any position where 'the outcome will be clear in three years' is worth multiplying the expected cost of after-sales repairs into before making a decision. The calculation is simple; the difficult part is whether anyone is willing to calculate it during the cost reduction meeting. ### Extended Judgment: The hidden variables that are most easily overlooked
In mass production accidents of dishwasher parts, half are not due to the wrong material selection, but because the hidden variables were not controlled.
The first variable is moisture content. The factory moisture content of PA series materials, drying conditions, and storage time before injection molding together determine the actual moisture content. If the moisture content is incorrect, both strength and appearance will be affected.
The second variable is the mold temperature. When the mold temperature is 20°C lower, the surface fiber floating and weld line strength may differ by a factor of two.
The third variable is the time after assembly. The torque, dimensions, and seal compression amount are all different after 24 hours and 30 days of assembly.
These three variables are not listed on the material properties table, but they are all included in the failure report.
Write these three things into a table and send it to the supplier; it’s more useful than making ten phone calls—the communication cost for selecting dishwasher parts is basically spent on repeatedly confirming these items.
Supplementary Note: Three On-Site Judgment Signals
Signal 1: Sprinkler arm water flow deviation, deformation of the hole edges. Scale erosion and softening of the hole edges—first check the washing hardness settings. For material issues, look at whether the hole edges are whitening—whitening indicates that alkaline hydrolysis is occurring.
Signal 2: The roller develops edges, and the slide rail gets grooves. The paired hardness does not match; replace with a wear-resistant brand, increase the hardness of the slide rail, and modify both ends together. If only one end is changed, it will still wear.
Signal 3: Water leakage at the inner tank welds. The inner tank is mostly made of stainless steel, and leakage often occurs at the seals — check the seal ring for permanent compression deformation and alkali resistance data. This part of the materials is the cheapest and also the easiest to be overlooked during inspection. ### Verification order: complete the three steps before placing an order.
Step one, set the working conditions: the three items of water temperature, detergent alkalinity, and number of cycles should be set according to the 'most severe user assumption'.
Step two, alkaline resistance test: High-temperature alkali soaking combined with mechanical wear test; soaking without movement or movement without soaking will both overestimate the lifespan.
Step three, inspect after-sales parts: Establish a ten-year after-sales curve tracking system for spray arms, rollers, and filters, allowing the data to subsequently guide material grading. Only after completing these three steps does the dishwasher's ten-year promise have a material foundation.
Conclusion
Some people may sell materials, but it's not certain that anyone will provide them—when it comes to choosing materials, the earlier you ask, the less trouble it will be.
The material selection and mold trial for this type of part can be discussed together.
