CPM

The Alfa Laval CPM Constant-Pressure Modulating Valve is a pneumatic regulating valve that maintains a constant pressure in hygienic process lines at the valve inlet or outlet. Safe, reliable and easy to clean, these regulating valves provide accurate pressure control, quickly adjusting position to maintain the pressure at pre-set values without any need for electronic control.

Regulating valve providing accurate inlet or outlet pressure in hygienic process lines

Safe, effective pressure control
Self-draining design
Excellent valve cleanability
Easy to install, simple to operate
High hygienic level

This pneumatic regulating valve maintains uniform inlet or outlet pressure in hygienic process lines for the dairy, food, beverage, personal care and many other industries. Typical applications include filling and bottling equipment.

Safe, effective pressure control

Alfa Laval Constant Pressure Modulating (CPM) valves are pneumatic regulating valves that maintain a constant inlet or outlet pressure in hygienic process lines. Thanks to a quick response diaphragm, these compact valves immediately react to any change in product pressure, adjusting position to keep the pressure at preset values.

Excellent valve cleanability

CPM valves feature a self-draining design and crevice-free, bowl-shaped valve body with welded valve seat to enable thorough cleaning, thus eliminating potential entrapment areas. The unique diaphragm with PTFE on the lower diaphragm also contributes to excellent cleanability.

Constant pressure valve range

Alfa Laval offers three types of CPM valves. Modular design enables the use of different plug sizes and different flow rates between 0.5 and 110 m3/h provide great operational flexibility.

Upon request, some CPM valves can be provided as ATEX-approved valves (group 2 category 3 D&G applications) for use in potentially explosive areas.

For more information, please refer to How it works and Documentation.

Compliance with most hygienic standards

Alfa Laval CPM valves meet most standards requested in the dairy, food and beverage, and personal care industries. Please refer to Documentation for more information.

Aseptic version

Designed to maintain a constant pressure at the valve inlet or outlet, using different plug sizes and different Kv values.

The diaphragm in the valve enables it under aseptic conditions to react effectively to any changes in product pressure by shifting position against a constant air pressure.

The CPM valve is often used upstream of aseptic filling and bottling machines.

Product Benefits

Safe, effective pressure control
Self-draining design
Excellent valve cleanability

工作原理

Construction

There are two different types of construction for Alfa Laval Constant Pressure Modulating valves.

The CPMI-2 and CPMO-2 valves consist of a valve body with valve seat, cover, a valve plug with a special diaphragm and a clamp. The diaphragm consists of two flexible EPDM diaphragms supported by 12 stainless steel sectors in between them. The cover and the valve body are clamped together. The valve body and the seat are welded together.

The CPM-I-D60 consists of a CPMI-2 valve with additional piping.

Operating principle

The CPMI-2, CPMO-2 and CPM-I-D60 valves are controlled remotely by means of compressed air. The valves operate without a transmitter in the product line and only require a pressure-regulating valve for the compressed air and a pressure gauge in the product line (see below).

Where modulating back pressure is required (i.e., to maintain a fixed flow in and out of the CPM valve), the air supply to the valve can be provided by an I/P converter (typically 3-15 psi) and a booster valve. The product pressure dictates the pressure ratio of the booster valve.

A diaphragm reacts immediately to any alteration of the product pressure and changes position so that the preset pressure is maintained.

Inlet side: The Constant Pressure Modulating Inlet (CPMI-2) valves and the Constant Pressure Modulating Inlet D60 (CPM-I-D60) valves maintain constant pressure in the process line at the inlet side of the valve. CPMI-2 and CPM-I-D60 open when product pressure increases and close when product pressure decreases. These are often installed downstream from separators and heat exchangers, and may also be used as overflow valves.

Outlet side: The Constant Pressure Modulating Outlet (CPMO-2) valves maintain constant pressure in the process line at the outlet side of the valve. CPMO-2 closes when product pressure increases and opens when product pressure decreases (see illustration below). It is often installed upstream from pasteurizers, separators and filler systems of filtration units.

Options

Fittings in accordance with required standard
Air pressure regulating valve kit, 0-8 bar
Diaphragm in PTFE covered in EPDM or PTFE
Seals in NBR, FPM or PTFE
Air throttling valve for adjustment of regulating speed for the CPM-2 valve
Booster for product pressure exceeding the available air pressure (Product pressure = 1.8 x air pressure)
3A version available on request for CPMI-2 and CPMO-2 valves only

Constant-Pressure Modulating Inlet Valve

Constant-Pressure Modulating Outlet Valve

Constant-Pressure Modulating Inlet Valve D60

Part of a broad valve range

Alfa Laval offers a comprehensive range of valves intended for hygienic applications in the dairy, food, beverage,home care, personal care, biotechnology and pharmaceuticals.