JONENG Sanitary Flow — 首页
CN
获取报价

您的询价清单

清单还是空的。在产品页面加入后，它会保留在这里。

3-A 标准对一只阀门究竟要求什么

规格书上的 3-A 标志常被当作一锤定音的证明。它能说明的比多数规格假设的要少，而分歧正是从这个缺口开始的。

A symbol, not a certificate

3-A Sanitary Standards publishes design criteria, and a manufacturer who believes a product meets them applies for authorisation to display the symbol. That authorisation is a claim about a design, verified by a third-party inspection of that design.

It is not a batch certificate. It does not travel with the valve in front of you the way a material certificate does, and it says nothing about whether this particular unit was assembled correctly. Those are separate documents and worth asking for separately.

What the criteria actually cover

The criteria are about cleanability. Surfaces in product contact have to be finished to a defined roughness, radii have to be large enough that a cleaning solution reaches the corner, and the assembly has to drain rather than hold a pool.

Materials are constrained too: the steel grades, the elastomers and the way a non-metallic part is bonded all have requirements. What is absent is anything about pressure rating, about cycle life, or about how the valve performs. A valve can be fully compliant and entirely unsuitable.

Where it differs from EHEDG

EHEDG tests rather than only prescribes. Its cleanability assessment puts a soiled test rig through a defined clean and measures what is left, which catches a design that satisfies every dimensional rule and still shelters a residue.

In practice they overlap heavily and a serious sanitary design satisfies both. Where a specification names one, it is usually worth asking whether the other is also required, because retrofitting a certification is considerably more expensive than specifying it.

What to ask for

Ask for three things rather than a symbol: the 3-A authorisation number and its expiry, the material certificates for the wetted parts, and the surface finish actually achieved rather than the one specified.

A supplier who can produce all three quickly is a supplier who has them. One who sends a logo has sent a logo.

继续阅读