FAQ - Sleeve for Pinch Valve

Although pinch valve sleeves are considered technically leak-tight, a diffusion of slightly volatile gases is still possible and cannot be ruled out. The most diffusion-tight elastomer in the AKO sleeve options is FPM (Viton).

The maximum operating pressure of the pinch valve sleeves depends on both the pinch valve types and the pinch valve series; see the data sheets for this or simply contact our sales team.

Yes, for certain mechanical pinch valves. Ask our sales department about them.

The fabric in the pinch valve sleeve serves, among other things, to provide compressive strength and to ensure the optimal functioning of a sleeve. Along with the actual rubber quality, the quality and arrangement are decisive for the high quality of the sleeve and the resulting service life.

Yes, the design of such a pinch valve sleeve is available, but its mechanical and physical properties are restricted. Please contact our sales team with your concrete application and requirements.

The sleeves of the air-operated pinch valves are manually assembled in the production process and then machined in several additional work steps into the final product. The entire process is very labour-intensive and accompanied by high wage costs. Therefore, among other things, the prices of the air-operated pinch valve sleeves cannot be compared with those of a piece of tubing in an extruded hose, for example. The mechanical pinch valve sleeves are also manually assembled items which are individually produced in special moulds. The entire manufacturing process is very time consuming and intensive in terms of labour costs.

The sleeves are largely "Made in Germany" in accordance with both our elastomer mixture and design specifications.

We use only premium additives in our elastomer mixtures. Thanks to many years of constant improvements in both the elastomer mixtures and the structural design of the sleeve, we have succeeded in applying our experience in the area of pinch valve control to increase the service lives of the pinch valve sleeves and thus the "Best total cost of ownership" to a maximum, resulting in a customer satisfaction level of 97%.

The markings provide information on the sleeve types, production batch and date of manufacture.

In the case of a defect, the manufacturer’s data can be traced back by means of the production batch of the air-operated pinch valve sleeves.

The possible switching cycles of a pinch valve depend on numerous factors and operating conditions such as the control/closing pressure, the media/operating pressure, the operating temperature and the operating medium. Unfortunately, no general statement can therefore be made about the switching cycle frequency. Thanks to our decades of experience, however, and hundreds of different applications, our sales team is able to estimate the switching cycle frequency based on information on all of the usage details for each pinch valve size and design; simply contact us with your usage details and we will be able to provide you with a rough estimate regarding the service life for your application. It can generally be said that the possible number of switching cycles drops as the pinch valve sizes and nominal widths increase. In our constant in-house endurance tests, the sleeves achieve from 50,000 to several million switching cycles depending on their size / nominal width and the control/closing pressure level. Feel free to contact us with your application details. We will then be able to provide you with a rough estimate of the switching cycle frequency for your application.

The essential criteria for this are presented in our operating manuals and should be complied with as closely as possible. We will naturally also be happy to advise you explicitly about your own application case.

No. The sleeves are structurally designed for our AKO pinch valves. External changes make them unsuitable for usage in pinch valves. Please contact us with the concrete deviating dimensional requirements of the pinch valve sleeve and we will be happy to advise you.

A large number of resistance tables for elastomers can be found on the Internet. If you do not have any personal experience or knowledge with regard to the resistance of our pinch valve sleeves, we will be happy to advise you or to make recommendations.

Due to its physical and mechanical properties by reason of a limited compression set, limited rebound resilience and limited tear resistance, PTFE is not suitable as pinch valve sleeve material.

The selection of the most suitable sleeve material always depends on the operating medium and the operating temperatures. It can generally be said that natural rubber is best suited for all bulk materials, sludge, dusts, suspensions with operating temperatures < 80°C without chemical additives and/or with no requirement with respect to chemical resistance. A design/specification should be made by our sales team for all other operating media having particular requirements such as those regarding chemical resistance, foodstuff compatibility and/or higher operating temperatures. Please do not hesitate to contact us at any time with your application details/requirements.

We have installation instructions in 12 languages and maintenance/repair instructions for every pinch valve type/series available on our website under the "Downloads" heading. They explain in detail how to replace the sleeves.

No, all of the pinch valve types are structurally designed so that the sleeve can be easily replaced on site without the need for special tools.

No. In addition to making the installation process easier, the assembly paste also ensures a tight fit of the sleeve in the clamping. Grease has the opposite effect and in the worst case, for example in contact with NR elastomer, can cause the NR elastomer to swell and decompose.

Depending on the elastomers, sleeves can be used without additional actions at temperatures as low as -10°C. Our experience shows that a large number of sleeves have already been installed in colder regions and applications without functional impairments.

The maximum operating temperatures of the pinch valve sleeves depend on the material/elastomer and are 130 °C for silicone and Viton.

The structure of our sleeves for the air-operated pinch valves consists of various components to ensure ideal function with respect to the restoring force and low rebound resistance. Therefore, the part of the pinch valve sleeve not contacting the medium/product is only resistant up to 80°C.

Yes, you can download the corresponding FDA certificate of conformity under the following link.
"Declaration of conformity"

An FDA conformity or EHEDG certificate for complete pinch valves in hygienic design (EHEDG certificate formerly only available in connection with EPDM quality)