Alfa Laval Constant Pressure Modulating Valves (CPM)
Alfa Laval Constant Pressure Modulating Valves (CPM)
CPM valves maintain uniform inlet (CPMI-2) or outlet (CPMO-2) pressure in hygienic process lines for the dairy, food and beverage industries. These regulating valves provide accurate pressure control, safe and reliable performance and excellent cleanability.
Models
- CPMI-2 (Inlet)
- CPMO-2 (Outlet)
CPM APPLICATION
Related Industries:
Processed Foods, Dairy, Beverages, Brewery, Home & Personal Care, Chemical
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.
Compliance with most hygienic standards
Alfa Laval CPM valves meet most standards requested in the dairy, food and beverage, and personal care industries. 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.
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
Alfa Laval Constant Pressure Modulating Inlet (CPMI) valves are sanitary constant-pressure valves for use in stainless steel pipe systems. The CPMI-2 valve maintains a constant pressure in the process line at the inlet side of the valve. Typical applications of this valve are after separators, heat exchangers, and as an overflow valve.
Working Principle
The CPMI-2 is remotely controlled by means of compressed air. The valve operates without a transmitter in the product line and requires only a pressure regulating valve for the compressed air and a pressure gauge in the product line.
A diaphragm/valve plug system reacts immediately to any alteration of the product pressure and changes position so that the preset pressure is maintained. CPMI-2 opens at increasing product pressure and vice versa.
Standard Design
The CPMI-2 consists of a valve body with valve seat, cover, a valve plug with a diaphragm unit, and a clamp. The diaphragm unit consists of a stainless steel disc—which is divided into sector—and flexible diaphragms that are placed on each side of the sectors. The cover and the valve body are clamped together. The valve body and the seat are welded together. The CPMI-2 meets 3-A standards.
Materials
| Product Wetted Steel Parts | 316L |
| Other Steel Parts | 304 |
| Lower Diaphragm | PTFE covered EPDM rubber (standard) Solid PTFE |
| Upper Diaphragm | Nitrile (NBR) standard PTFE covered EPDM rubber Solid PTFE |
| O-ring | Buna (standard) Fluorinated rubber (FPM) covered EPDM rubber |
| Finish | 32 Ra |
Technical Data
| Max Product Pressure | 145 psi |
| Min Product Pressure | 0 psi |
| Max Product Viscosity | 500 cps |
| Temperature Range | 14 – 203°F |
| Temperature Range with PTFE/EPDM Upper Diaphragm | 14 – 286°F (higher on request) |
| Air Pressure | 0 – 116 psi |
| Air Connections | R ¼ inch (BSP), internal thread |
Options
Plug size (Cv 23, Cv 8, Cv 10, or Cv 2/18)
Ordering Options
- Diaphragm type if not standard
- Connections if not welding ends
- Optional equipment if needed
Optional Equipment
- Male parts or clamp liners in accordance with required standard
- Pressure gauge 0 – 87 psi, 1½ inch
- Pressure gauge 0 – 145 psi, 1½ inch
- Air pressure regulating valve kit, 0 – 116 psi
- Air throttling valve for adjustment of regulating speed for the CPM-2 valve
- Booster for product pressure (product pressure = 1.8 x air pressure) exceeding the available air pressure
- 3-A Sanitary Standard labelling on request
The Alfa Laval CPMO-2 (Constant Pressure Modulating Outlet) is a sanitary constant pressure valve for use in stainless steel pipe systems. The CPMO-2 maintains a constant pressure in the process line at the outlet side of the valve.
A CPMO-2 valve is typically used before filling or bottling machines and in other applications where constant pressure must be maintained.
Working Principle
CPMO-2 is remotely controlled by means of compressed air. The valve operates without a transmitter in the product line and requires only a pressure regulating valve for the compressed air and a pressure gauge in the product line.
A diaphragm/valve plug system reacts immediately to any alteration of the product pressure and changes position so that the preset pressure is maintained. CPMO-2 closes at increasing product pressure and vice versa.
Standard Design
The CPMO-2 consists of a valve body with valve seat, cover, a valve plug with a diaphragm unit, and a clamp. The diaphragm unit consists of a stainless steel disc—which is divided into sectors—and flexible diaphragms that are placed on each side of the sectors. The cover and the valve body are clamped together. The valve body and the seat are welded together. The CPMO-2 meets 3-A standards.
Materials Table
| Product Wetted Steel Parts | 316L |
| Other Steel Parts | 304 |
| Lower Diaphragm | PTFE covered EPDM rubber (standard) Solid PTFE (optional) |
| Upper Diaphragm | Nitrile (NBR) standard PTFE covered EPDM rubber (optional) Solid PTFE (optional) |
| O-ring | Buna (standard) Fluorinated rubber (FPM) covered EPDM rubber (optional) |
| Finish | 32 Ra |
Technical Data Table
| Max Product Pressure | 145 psi |
| Min Product Pressure | 0 psi |
| Max Product Viscosity | 500 cps |
| Temperature Range | 14 – 203°F |
| Temperature Range with PTFE/EPDM Upper Diaphragm | 14 – 286°F (higher on request) |
| Air pressure | 0 – 116 psi |
| Air connections | R ¼ inch (BSP), internal thread |
Ordering Options
- Plug size (Cv 23, Cv 8, Cv 10, or Cv 2/18)
- Diaphragm type if not standard
- Connections if not welding ends
- Optional equipment if needed
Optional Equipment
- Male parts or clamp liners in accordance with required standard
- Pressure gauge 0 – 87 psi, 1½ inch
- Pressure gauge 0 – 145 psi, 1½ inch
- Air pressure regulating valve kit, 0 – 116 psi
- Air throttling valve for adjustment of regulating speed for the CPM-2 valve
- Booster for product pressure (product pressure = 1.8 x air pressure) exceeding the available air pressure
- 3-A Sanitary Standard labelling on request
Instruction manual – CPM Valve – EN
PD Sheet – CPM Constant-Pressure Modulating Valve – EN
Instruction Manual CPM-2 Constant-Pressure Modulating Valve
Instruction Manual CPM-I-D60 Constant-Pressure Modulating Inlet Valve
Need consistent pressure in your hygienic process line? Contact us to select the right Alfa Laval CPM valve configuration for your application.