The XNFM VF series pinch valve uses compressed air to pinch a reinforced rubber element, so the medium only ever touches the rubber sleeve — making it the simplest and most economical shut-off valve for abrasive powders, granular solids and fiber-containing slurries.

Figure 1. XNFM VF series air operated pinch valve — cutaway view showing the rubber sleeve closed by compressed air.

What Is an Air Operated Pinch Valve?

An air operated pinch valve, also called a pneumatic pinch valve, is a flexible-sleeve control valve that opens and closes by pinching a rubber element — the only wetted part. The body is filled with compressed air from a 3/2-way solenoid or pilot valve; raising the air pressure closes the sleeve, exhausting it opens the sleeve.

Because the flowing medium never touches metal, the XNFM VF pinch valve is uniquely suited to abrasive powders, corrosive slurries, fibrous materials and viscous fluids that would destroy a conventional ball, butterfly or gate valve. When the sleeve eventually wears out, you replace one rubber component and the valve is essentially new again — no metal parts need to be replaced.

How the XNFM VF Pinch Valve Works

The VF series uses a sac-type soft-seal structure: a one-piece elastomer sleeve sits inside an aluminum alloy body. The sleeve is the only part in contact with the medium. When the solenoid or pilot valve sends compressed air into the body cavity, the air pressure collapses the sleeve from the outside, completely closing the bore. When the air is vented, the sleeve springs back to its full round shape and flow resumes.

Operation is fully pneumatic — no electric actuator, gearbox or separate drive mechanism is required. Only a 3/2-way solenoid valve or pilot valve is needed to control the VF, which makes it one of the most economical shut-off solutions on the market.

Key Features at a Glance

●Simple structure — one rubber sleeve does all the work, no metal-to-medium contact.

●Low-cost maintenance — at end of sleeve life, replace only the rubber; the rest of the valve is reusable.

●Cost-effective — cheaper than lined butterfly valves, diaphragm valves or ball valves in abrasive duties.

●ATEX compliant — explosion-proof design per 2014/34/EU (VFX variant).

●PED compliant — complies with 2014/68/EU Pressure Equipment Directive.

●Versatile flange options — five flange variations to suit aluminum or steel piping.

●Wide sleeve selection — 14 rubber materials cover food, abrasive, high-temp, anti-static and chemical-resistant duties.

Figure 2. XNFM VF series pinch valve — five flange variations and full dimensional data, DN40 to DN300.

VF Series Pinch Valve Specifications

Item Specification

Model VF (VFX for ATEX explosion-proof design)

Brand XNFM

Nominal diameter DN40 / 50 / 65 / 80 / 100 / 125 / 150 / 200 / 250 / 300 mm

Body material Aluminum alloy (standard); stainless steel on request

Flange material Aluminum alloy

Sleeve (spool) material Natural rubber, food-grade NR, NR high-temp, EPDM, EPDM food black, EPDM food pale, NBR, NBR food black, NBR food pale, FPM/FKM, silicone, CR, CSM, IIR, anti-static NR

Structure Sac type (full-bore elastomer sleeve)

Seal form Soft seal

Surface finish Powder coated 60–80 µm, white RAL 9010

Operating / medium pressure (max) 3.0 – 6.0 bar

Control / closing pressure (max) 5.0 – 8.0 bar

Differential pressure 2.0 – 3.5 bar (varies with diameter / sleeve)

Operating temperature −20 °C to +150 °C (depending on sleeve)

Flange connection DIN PN 10 (ANSI on request)

Compliance PED 2014/68/EU; ATEX 2014/34/EU (VFX)

Packing Carton, wooden case

Origin Zhejiang Wenzhou, China

Customization Available on request

Flange Variations

To match existing piping materials and installation preferences, the VF series offers five flange options:

1.Aluminum flange — standard, lightest weight.

2.Aluminum flange with steel / stainless steel bushing — for steel-pipe connections.

3.Aluminum flange with internal thread — threaded pipe joints.

4.Aluminum flange with steel / stainless steel bushing and internal thread — for conical external thread (R) connection.

5.Aluminum flange with flange sleeve — slip-on connection.

Sleeve Material Selection

The rubber sleeve determines chemical compatibility, temperature range and food-safety status. Choose the right material to extend service life:

●Natural Rubber (NR) — anti-abrasive; general-purpose for powders, granules and slurries.

●NR food quality — pale color, food-contact safe.

●NR high temperature — extended upper temperature limit.

●EPDM — good chemical and steam resistance.

●EPDM food black / food pale — food-contact certified.

●NBR / NBR food black / food pale — oil and grease resistant.

●FPM / FKM — aggressive chemicals, acids and solvents.

●Silicone, CR, CSM, IIR — specialty applications including chemicals, weathering and gas handling.

Where the VF Pinch Valve Excels

With wear-resistant, corrosion-resistant and high-temperature-resistant rubber sleeves, the XNFM VF series is widely used for switch control and flow control of:

●Abrasive powders, granules and particles

●Solids / liquids mixtures with fibers or viscose

●Corrosive and abrasive slurries

●Powder and granular pneumatic conveying lines

Main industries served: mining & metallurgy, ceramics, petrochemical, plastics, pulp & paper, energy, water treatment, equipment process control, pneumatic conveying. The VF pinch valve can substitute for butterfly valves, ball valves, diaphragm valves and plug valves in duties where those traditional valves fail prematurely.

Need a Pinch Valve for Your Abrasive or Corrosive Duty?

Send us the medium, particle size, temperature and pressure. The XNFM team will recommend the correct VF sleeve material, flange variation and size for your line.

Contact: sales@xnvalves.com | Website: https://www.xnvalves.com