About wu.zhigang

Zhigang Wu (吴治钢)
Tel: +86 (0)186-0215-3036
Fax: +86 (0)21-5196-3159
Email: wu.zhigang@filtertesting.com
QQ: 7252750 






1 / 1
文章编辑: 可视编辑

All cartridge filters are good, Some are better!

Filtering cartridges are very common products used in many industrial processes to clarify/decontaminate a broad variety of liquids (beverage, pharmaceutics, chemicals, paints, varnishes, blood, drinking water,…) and on as many types of machines (aircrafts, engines, boats, fluid power systems, road and off-road vehicles, machine tools,…).

If efficient, all filtering cartridges, whatever their type, clog, what means their differential pressure increases and/or flowrate decays. Then they cannot fulfil their function correctly and need being replaced. This creates a huge market of renewable products with plenty of suppliers offering very diverse cartridges.
Criteria to choose a cartridge and its supplier rather than another one strongly depend on its application. But in all cases, the key criterion is filtration efficiency. another one possibly being retention capacity.
Filtration efficiency guarantees the quality of the filtered liquid. It is specified/expressed by a percentage of efficiency in percent or a filtration ratio (e.g. ß) at a given particle size or by a rating, i.e. a particle size supposed to correspond to a given, often not claimed, efficiency.
Since the efficiency measurement method, equipment and products directly impact the values of efficiency, many professional sectors, including filter cartridge manufacturers and their end users agree on standard methods, often a compromise between technical and cost requirements, such as ASTM, NFPA, SAE or ISO standards.
All standard procedures allow variations of different details, e.g. accuracy of measuring instruments, variations in test conditions, type of equipment, validation criteria, etc. This means that performances claimed according to any standard by any manufacturer may not be comparable to those claimed by a competitor for the same application.
Thus only independent third party testing centre results can really be trusted when evaluating competing products.

文章编辑: 可视编辑


Figure 1: Before and after a collapse test当你使用固液分离或者液液分离过滤器来服务于挑剔的工况以确保质量和重复性的时候。是否能够有效地过滤掉可能损坏设备的杂质颗粒或者是否从燃油里去除水分以延长系统服务时间是非常重要的,不恰当的过滤器器设计和滤材的选择将可能导致灾难性的失效。

文章编辑: 可视编辑

The “DNA” of Your Filter and Filter Media

When used in solid-liquid and liquid-liquid separation applications filters serve a critical function to ensure process quality and repeatability. Whether it could remove the particulates that can damage equipment or remove water from fuel to extend system service life is very important. Improper filter design and filter media selection can result in catastrophic failure.
The concept that filters have a specific "DNA" may seem odd but just as Deoxyribonucleic Acid ("DNA') defines the nature of the human body, there is a "DNA" associated with a filter that defines how it will perform. Filters are used to separate many different particles and liquids. The effectiveness and efficiency of filters can be determined by laboratory testing before expensive plant modifications are made for real world use. For instance, most filters and filter media have an "unloading point" that is a measureable differential pressure at which filters release trapped contaminants downstream. The correct testing can find these "unloading points". These released downstream particulates can erode or ruin an engine, cause scrap in food and beverage processing, or may even seize mechanical system components. Even before the burst point where the particulates downstream increase, due to change in pressure or other external conditions, can still destroy the system. Each filter has its own attributes and to determine them you need to consider multiple tests to define the "DNA" of a filter.
The testing to determine the "DNA" of a filter is much more inclusive than simple initial efficiency, mean pore flow or bubble point testing techniques. While these provide a good starting point, “DNA” testing is more holistic than the above-mentioned tests that provide only one small detail about the filter. The idea of knowing more about a filter is essential in determining where the filter would perform the best and where it will perform the worst. “DNA” tests using international standards provide results that are repeatable and allow “apple to apple” comparison with other filters and their applications.
The “DNA” of a filter is formed from the results of various tests depending on the process application.
The tests that help form the “DNA” of the filter include:
文章编辑: 可视编辑

How Do Smart Manufacturers Prove Their Product Is Better Than the Competition’s and save Testing cost?

Filter is a consumable product which needs replacing termly, the market is huge; the competition is very fierce. Almost each filter manufacturer has many competitors in different application fields. Undoubtedly, each filter manufacturer hopes to gain more business by proving to the customer that their own products have better cost performance than their competitor(s).

Analyse the performance of competitor’s product, compare with their own product and the customers’ requirement is the most common strategy. Many filter manufacturers invest their own test lab that has the capability of facing to the OEM customers; they buy testing equipments for research & development works and the analysis of competitors. During the certificating process by the OEM customers (filter users), test ability is an indispensable part.

But, there have so many testing items for a filter. No one could equip all the test equipments. And there also exist the risk to the filter manufacturer when they developing new OEM customer, they need to prove to the customer their lab is capable and trustable. A smart filter manufacturer will evaluate the quantity of each test item instead of invest the test equipments blindly; Even they have the test ability for a test item, some manufacturers prefer to choose presenting test report by the third party lab, it is helpful to impress the customer and shows the ability of themselves. 

IFTS founded in 1981, it is a fully independent and professional liquid filter testing organization; Acting as the Europe filter testing centre and the world reference lab, IFTS is in service to hundreds of the customers around the world. Filter manufacturers use IFTS’s third party testing report to prove the performance of their product(s) to the customer, the filter users use IFTS’s services for monitoring the performance of the suppliers. There have some successful stories that the manufacturers gained the good business without investing the test equipments.

文章编辑: 可视编辑





  IFTS 作为一家成立于1981年的专业第三方液体滤清器测试机构,作为欧洲过滤测试中心和世界参考级实验室,为全球数百家客户提供独立的测试服务。制造商客户通过IFTS的检测报告来向他们的客户证明自己产品的性能,而主机厂客户则通过IFTS的检测报告来监督供应商的质量。不论是滤清器产品的用户还是制造商都能从中获益。一些初期尚不具备某项目测试能力的生产商利用IFTS的资源,在不投资检测设备的情况下依旧获得了可观的订单。

文章编辑: 可视编辑

ISO/TR 13353(1994)标准已不再有效

  近来,我们接到不少中国客户关于依据ISO/TR 13353(1994)标准对燃油滤清器进行性能测试的咨询,他们希望我们依据这个标准来进行试验。

  ISO/TR 13353(1994) 是一个旧的标准,早在2002年8月29日就已经撤销了。我们向这些客户解释:我们IFTS还有一些可用的ACFTD,我们可以将测试得到的µm(c)转换成µm,这也是我们可以使用这个旧标准做测试的原因。



  在1994年,IFTS创建起草了ISO TR 13353标准用来评估燃油滤清器的过滤效率和容灰量,BOSCH接受并使用了该标准。ISO TR 13353 (1994) 分为两个部分:第一部分是用于评估滤清器的初始效率(单次通过循环,5mg/L 的ACFTD ——过滤效率表述为多少µm的粒子效率是多少;第二部分是用于评估滤清器的容灰量(多次通过循环,50mg/L 的ACFTD,终止条件为压差上升70kPa)

  自从1999年起,ACFTD已经不再生产;被ISO MTD取代。而且颗粒计数器的标定标准也由ISO 4402(1991)升级到了ISO 11171(1999)。延伸阅读:试验粉尘的历史(英文版中文版);

  ISO/TS 13353(2002)是作为评估初始效率的标准而被重新审核评估的(使用上游杂质浓度 5mg/L 的ISO MTD,单次通过——过滤效率表述为多少µm (c)的粒子的过滤效率是多少。

ISO 19438 (03)被用于评估滤清器的效率和容灰量的评估,使用的是50mg/L ISO MTD,使用在线稀释系统便于颗粒计数——过滤效率表述为多少µm (c)的粒子的过滤效率是多少。

  也就是说,现如今,ISO/TR 13353(1994) 已经无效,被ISO 19438(2003)所取代。

  于2004年进行的全球比对试验证明了在初始效率测试方面,使用ISO TS 13353 (02) 或 ISO 19438 (03)获得的结果是相似的。通常来说,包括BOSCH在内的燃油滤清器用户(或发动机主机厂)应该已经有了接受ISO 19438的规范。

  上述所有的标准替代,您均可通过在ISO官方网站上查询标准号来找到替换记录,比如下图中用红色圈出的部分显示了ISO/TS 13353(2002)曾替代了ISO/TR 13353(1994),并被ISO 19438(2003)替代。

关于新旧颗粒尺寸读取及转换,我们推荐您购买ISO/TR 16386(1999)阅读了解。

文章编辑: 可视编辑

ISO/TR 13353:1994 is no longer available

Recently, we have got some inquires for fuel filter testing according to ISO/TR 13353(1994) from the customers in China, they asked us to run test for them according to this standard.

ISO/TR 13353(1994) is an old test standard which has already been withdrew on August 29th of 2002. We explained that we have some more ACFTD available by IFTS and we can correlate from µm(c) to µm. That is the reason why we can work according to this old standard.
These Chinese customer told us their customers (the filter end users) ask them to use this standard to test the fuel filter.
This article introduces the upgrading of this testing standard for diesel fuel filters. Try to help filter users and filter manufacturers to understand the background of this testing standard.
ISO/TR 13353(1994) was founded by IFTS and accepted by BOSCH in 1994. It is in order to qualify the filtration efficiency and the retention capacity of fuel filters. This procedure is divided in two parts: a first one is dedicated with the determination of the initial filtration efficiency (singlepass circulation at 5 mg/L of ACFTD – expression of the filtration ratings in µm); The second one is dedicated with the determination of the retention capacity (multipass recirculation at 50 mg/L of ACFTD up to an increase of DP of 70 kPa).
Since 1999, the ACFTD no more available ; it has been replaced by ISO MTD and the calibration for the APC (automatic particle counter) has been upgraded: the ISO 4402(1991) has been revised by the ISO 11171(1999). About dust history, please read here.
ISO/TS 13353(2002) has been reviewed and is only dealing with the determination of the initial filtration efficiency (according to a BUGL of 5 mg/L of ISO MTD in a single pass way – expression of the filtration ratings in µm(c) ).
ISO 19438 (2003) has been standardised for determining both the filtration efficiency and the retention capacity with working in a multipass recirculation with a BUGL of 50 mg/L of ISO MTD and on line dilution concerning particle counting – expression of the filtration ratings in µm(c) ).
That is to say, nowadays, ISO/TR 13353 (1994) is no more available. Has been replaced by ISO 19438(2003).
Last round robin tests in 2004 have proven that the determination of the initial filtration efficiency is similar whatever using ISO/TS 13353 (2002) or ISO 19438 (2003). Normally, including BOSCH, the fuel filter users should make the specification with using ISO 19438 procedure.
All above standards’ upgrading, you could find records on the official ISO website. For example, you could find the revision information for ISO/TS 13353(2002) in below image, it revised ISO/TR 13353(1994) and has been revised by ISO 19438:


For more detailed historical background, we suggest you to refer to ISO/TR 16386(1999).

文章编辑: 可视编辑

How to Optimize the Choice of Filtering Media


Liquid filter media all have the same role of letting the liquid flow through whilst retaining a part if not all particles in suspension. Liquid filtration occurs in a very broad variety of processes and equipments, from engines fuel or lubricating oil to drinking water through chemicals, blood or varnishes.

Depending on the type of filter used, filtering media are of made of layers of grains (sand or diatomites) or of fibers, which can be wound or processed or papers.

The variety of techniques, processes and liquids they are applied to create a broad spectrum of technical requirements and properties. Tests are developed to evaluate these properties in accelerated conditions, cheaper and much faster than actual operation ones.

The lecture will present an overview of the characteristics of filter media (from granular ones to sterilizing membranes) classified in four families: intrinsical relating to the internal structure of the porous media, hydraulic which cover the impact of the media on the fluid flow, performances, i.e. how the media retains particles or undesirable substances and the impact of their retention on both the permeability and the efficiency and compatibilities, including all “negative” interactions between the media material and the filtered fluid.

Main test procedures (especially standard ones) will be summarised. A brief presentation will be made of their principles, of the equipments and products used, of the criteria of validation of test benches.

The way raw data have to be processed to obtain standard test report will be explained and typical interpretation of data oriented toward the optimisation of the choice of filtering media will be given.

By: Christophe PEUCHOT, Managing Director

Translate by: Zhigang WU, Asian Market Manager

Read the Chinese version of this article

文章编辑: 可视编辑





2012 年的归档

五月 六月 九月

2011 年的归档

七月 八月 九月 十二月


DeepEyes Version 1.2.21