龙头下面天天一滩水，客户以为没拧紧。密封圈压变没选对，拧再紧也漏。
滴水不是没拧紧，是圈压变超标
水龙头密封圈是“密封耐水的件”：密封、耐水、耐压。材料要密封、耐水、耐压——结论先给：水龙头密封圈用 SEBS 基 TPE 是主流；高压龙头，TPV 优先。
水龙头密封圈最大的坑：性能不达标，先查配方再查工艺。性能不达标，配方先查——配方，是密封圈的查案顺序。
水龙头密封圈是功能件：漏水、开裂都是问题。材料选对，龙头才稳——功能件，别省料钱。
冷热水流反复冲，为什么选TPE
水龙头密封圈用 TPE 的理由：密封可做、耐水可做、耐压可做、效率高——四条合起来，适合密封圈。
密封是核心：防漏密封。密封测试写进验收——漏水，就是问题。
耐水不能省：长期通水。耐水测试写进验收——变形，就是问题。
通水、加压、冷热，三关各看什么
通水工况：长期通水。耐水数据要验——变形，就是问题。
加压工况：水压冲击。耐压数据要验——开裂，就是问题。
冷热工况：冷热交替。耐温数据要验——变形，就是问题。
TPE密封圈对阵橡胶，龙头选谁
| 维度 | SEBS基TPE | 橡胶 |
|---|
| 密封 | 可做 | 好 |
| 耐水 | 可做 | 好 |
| 耐压 | 可做 | 好 |
| 成本 | 中 | 中高 |
| 效率 | 注塑 | 硫化 |
| 用途 | 主流 | 高压 |
表格读法：橡胶耐压好但硫化慢；TPE 效率高——主流密封圈 TPE，高压橡胶。
按压力选：高压橡胶，主流 TPE。
装上去不滴不漏，验收测这四项
| 顺序 | 项目 | 说明 |
|---|
| 一 | 配方 | 先查 |
| 二 | 工艺 | 再查 |
| 三 | 模具 | 后查 |
| 四 | 机台 | 最后 |
表格读法：密封不行先拆样片，从配方体系到机台参数顺一遍——别一上来换料，顺序错了越改越乱。
配方，是密封圈的查案顺序。
只信样品不试装，装完就渗水
坑一：直接换料。新料换一圈问题还在，根子可能在工艺——密封件出问题，先排配方再排工艺。
坑二：耐压漏测。开裂——耐压测试，必测。
坑三：耐温漏测。变形——耐温测试，必测。
水温、压缩量、标准——定圈前问清
三问：水压多少、水温多少、密封按什么标准。一验：实际使用实测——三问一验，供应商底细清楚。
配方验证要先行：先留样核对配方体系和硬度，再去对工艺窗口。先查配方，再谈价格——配方，是密封圈的查案顺序。
留样要成习惯：每批留样，密封耐水按批次复测。批次换料先对比再放量——批次稳，客诉少。
滴漏、变形、老化：故障对照一张表
| 现象 | 原因 | 对策 |
|---|
| 漏水 | 密封不足 | 换高密封料 |
| 变形 | 耐水不足 | 换耐水料 |
| 开裂 | 耐压不足 | 换耐压料 |
| 异味 | 助剂析出 | 换低析出料 |
| 批次漂移 | 配方波动 | 锁窗口 |
水龙头密封圈漏水，先别怪材料——多半是压缩量没算对。 密封件压缩量按15%-25%设计，压超30%回弹就回不来；SEBS基TPE免硫化可注塑，是主流水龙头圈。
压变大于30%（70℃×22h）的料，别做天天受压的水封。 每批留样测压变；80℃以上热水、高压冲击工况改TPV基，TPV近橡胶耐温耐压。
下单前把水压和水温写进规格书，别只说“密封圈”三个字。 常温冷水SEBS基够用，打压按实际水压1.5倍核；出口件食品接触报告按批次核。
圈装一周就“回弹不动”、龙头开始渗水——压变超标就是这么翻车的。 冷热交替反复胀缩，低压变配方才扛得住；圈体要软糯贴合、不硬脆。
SEBS换TPV后硬度批次稳了，低温弯折一次过。 免硫化、边角料可回用，交期比硫化橡胶快；批次留样按季度复测压变。
水龙头密封圈天天受压、碰水，TPE 要压变小、耐水，压久了回弹不回就漏水。
密封压缩量按 15%-25% 设计；选低压变 TPE，70℃×22h 压变低于 30%，冷热循环不渗、和龙头口贴合。
卫浴密封件过冷热和水垢，耐温水、耐清洗剂要一起验。
普通料久泡热水发黏；选耐温水配方，每批测压变和浸泡后回弹，换料先小批装龙头试水。
水龙头密封圈收尾验收：压变、冷热循环、贴合三项随批走。
每批留样测压变低于 30% 和冷热循环渗漏，回弹如初；批次换料先小批装龙头试水，不渗再放行。
科隆客户案例：硬度批次漂移，换体系过低温弯折
东莞一家家居日用厂，水龙头密封圈硬度批次漂移，手感忽软忽硬。科隆配合换体系换牌号（SEBS 基换 TPV 基），硬度稳定，-40℃ 低温弯折一次通过。体系换了，批次问题从源头断——批次漂移，先看体系稳定性。
小结
水龙头密封圈的选型，配方先查，密封再测，性能不达标先查配方再查工艺，配方是查案顺序。
三行说清我们是谁：
改性能——改性热塑性弹性体、改性尼龙（PA6 / PA66 / PA46 / PA11 / PA12 / PA6T / PA9T 及尼龙合金）、改性 PPO / PPS；
有货源——各大化工巨头尼龙树脂、副牌料、大包料现货；
给判断——什么件，用什么料。
There is a puddle of water under the faucet every day, and the customer thinks it wasn’t tightened properly. The sealing ring was not chosen correctly, and no matter how tight it is screwed, it still leaks.
The dripping water isn't because it wasn't tightened, but because the hoop pressure exceeded the standard.
Faucet seals are 'components that are waterproof': sealing, water-resistant, and pressure-resistant. The material must be sealing, water-resistant, and pressure-resistant — conclusion first: SEBS-based TPE is mainstream for faucet seals; for high-pressure faucets, TPV is preferred.
The biggest pitfall of faucet seals: if performance is substandard, first check the formulation, then the process. If performance is substandard, check the formulation first——the formulation is the investigation order for seals.
The faucet seal is a functional part: leaks and cracks are both problems. Only by choosing the right material will the faucet be stable—functional parts, don't skimp on the material cost.
Repeated flushing with hot and cold water, why choose TPE
Reasons for using TPE for faucet seals: can provide sealing, can resist water, can withstand pressure, high efficiency—these four combined make it suitable for seals.
Sealing is key: leak-proof sealing. Seal testing is written into the acceptance criteria—if there is leakage, it is a problem.
Water resistance cannot be compromised: continuous water exposure over a long period. Water resistance testing should be included in the acceptance check—any deformation is a problem.
Water flow, pressurization, hot and cold—what to check for each of the three switches
Water flow condition: continuous water flow for a long period. Water resistance data must be tested—deformation is a problem.
Pressurized condition: water pressure shock. Pressure resistance data must be tested—if it cracks, it's a problem.
Hot and cold working conditions: alternating hot and cold. Temperature resistance data must be tested—deformation indicates a problem.
TPE sealing ring versus rubber, which one to choose for the faucet
| Dimension | SEBS-based TPE | Rubber |
|---|
| Seal | Can do | Good |
| Water-resistant | Can do | Good |
| Withstand pressure | Can do | Good |
| Cost | middle | Medium-high |
| Efficiency | Injection molding | Vulcanization |
| Purpose | mainstream | High pressure |
Table reading: Rubber has good pressure resistance but slow vulcanization; TPE is efficient — mainstream sealing rings use TPE, high-pressure rubber.
Choose by pressure: high-pressure rubber, mainstream TPE.
Installed without any leaks, inspection tests these four items
| Order | Project | Explanation |
|---|
| One | Recipe | Check first |
| Two | Craft | Check again |
| Three | Mold | Check later |
| Four | Machine | Finally |
How to read the table: If sealing doesn't work, first take apart the sample piece, then go through the formulation system to machine parameters step by step—don't start by changing materials right away; if the order is wrong, the more you change, the messier it gets.
The formula is the investigation sequence of the sealing ring.
Only trust the sample without test fitting, once installed it leaks
Pitfall 1: Directly changing the material. Even after changing to a new batch of material, the problem still exists. The root cause might be in the process—the sealing component is problematic, so first check the formula, then check the process.
Pitfall 2: Missed pressure testing. Cracking — pressure testing is a must.
Pitfall three: Temperature resistance leakage testing. Deformation — temperature resistance testing must be conducted.
Water temperature, compression amount, standards—ask clearly before setting the ring
Three questions: what is the water pressure, what is the water temperature, and according to what standard is the sealing? One verification: measured in actual use — three questions and one verification, the supplier's details are clear.
Formula verification must come first: first reserve samples to check the formula system and hardness, then move on to the process window. Check the formula first, then discuss the price—the formula is the sequence for investigating sealing rings.
Making sample retention a habit: retain samples from each batch, seal them and test them batch by batch for water resistance. When changing materials between batches, compare first before scaling up — stable batches result in fewer customer complaints.
Dripping, Deformation, Aging: A Comparison Table of Faults
| Phenomenon | Reason | Countermeasure |
|---|
| Water leakage | Insufficient sealing | Replace with high-density sealant |
| Transformation | Insufficient water resistance | Replace with waterproof material |
| Cracking | Insufficient pressure resistance | Change to high-voltage resistant material |
| Odor | Additive precipitation | Switch to low precipitation material |
| Batch Drift | Formula fluctuation | Lock window |
If the faucet seal ring leaks, don't blame the material first—it is mostly because the compression amount was not calculated correctly. The compression of the sealing part is designed at 15%-25%; if it is compressed over 30%, it won't rebound. SEBS-based TPE can be injection molded without vulcanization and is the mainstream material for faucet rings.
For materials with a compression set greater than 30% (70°C × 22h), do not make water seals that are under constant pressure. Keep samples from each batch to measure the compression set; for conditions with hot water above 80°C or high-pressure impact, switch to TPV-based material, as TPV is close to rubber in heat and pressure resistance.
Before placing the order, write the water pressure and water temperature into the specifications, don't just say the three words 'sealing ring.' For normal temperature cold water, SEBS material is sufficient; pressure testing should be based on 1.5 times the actual water pressure; food contact reports for outlet parts should be checked by batch.
After just a week of coiling, it 'rebounds without moving,' and the leading part begins to leak — over-standard pressure change is how it fails. Repeated expansion and contraction with alternating hot and cold, only a low-pressure change formula can withstand it; the coil body should be soft and snug, not hard and brittle.
After switching from SEBS to TPV, the hardness of batches has stabilized, and it passes low-temperature bending in one go. No vulcanization is required, scrap material can be reused, and the delivery time is faster than vulcanized rubber; batch samples are retested for compression set quarterly.
The faucet sealing ring is under pressure and exposed to water every day. TPE needs to have low compression set and water resistance. If compressed for a long time and it doesn't rebound, it will leak.
The sealing compression is designed at 15%-25%; select low-pressure vulcanized TPE, with compression set at 70°C × 22h less than 30%, no leakage during hot and cold cycles, and it fits closely with the faucet mouth.
Bathroom seals should be tested for hot and cold conditions as well as limescale, and both temperature-resistant water and cleaning agents need to be tested together.
Ordinary materials become sticky after soaking in hot water for a long time; choose temperature-resistant formulations, test each batch for pressure variation and rebound after soaking, and when changing materials, first test a small batch with the faucet.
Faucet sealing ring final inspection: compression set, hot and cold cycling, and adhesion tests are conducted batch by batch.
Each batch's retained sample pressure drop is below 30%, and there is no leakage during hot and cold cycles, with rebound as before; when changing batch materials, first test a small batch with the faucet, and release it if there is no leakage.
Cologne Customer Case: Hardness Batch Drift, System Change Leads to Too Low Temperature Bending
A daily household products factory in Dongguan experienced batch-to-batch drift in the hardness of faucet seals, causing the feel to be sometimes soft and sometimes hard. Cologne cooperated by changing the system and brand (from SEBS-based to TPV-based), achieving stable hardness and passing the -40℃ low-temperature bend test on the first try. By changing the system, the batch issues were eliminated from the source — when there is batch drift, first check the system stability.
Summary
For the selection of faucet seals, first check the formulation, then test the seal. If the performance is not up to standard, first check the formulation, then check the process. The formulation is the primary point of reference.
Explain who we are in three lines:
Modify performance — Modified thermoplastic elastomers, modified nylon (PA6 / PA66 / PA46 / PA11 / PA12 / PA6T / PA9T and nylon alloys), modified PPO / PPS;
Supply available — Nylon resins from major chemical giants, secondary-grade materials, bulk materials in stock;
Provide judgment — Which part requires which material.
