BT-Maric constant flow valves
– are designed to deliver a predetermined, constant flow rate for water

The BT-Maric constant flow valves (sometimes called flow regulation valves, flow limiters and flow control valves) maintain a fixed, pre-set (non-adjustable), constant flow rate, regardless of pressure. BT-Maric flow restrictors will keep the flow rate of a liquid in a pipe system to a specified value, regardless of pressure variations.

Bertfelt is the leading manufacturer of BT-Maric constant flow valves for industrial use.

flow rates from 0,15/L min to 8.854 l/min

Close-up of precise BT-Maric constant flow valves for industrial use

Precise constant flow valves

Bertfelt offers a complete range (flow rates from 0,15 L/min to 8.854 L/min) of precise constant fluid flow valves for industrial use
– that saves water and makes products and processes more efficient.

We also offer Tailor-made OEM solutions in order to meet our OEM Manufacturers customer challenges.

BT-Maric constant flow valves used across industrial, marine and farming applications

Used in many different applications

Our flow limiters are used in many different industries and applications such as process and food industries, water treatment, pump & filter protection, fire fighting, marine applications, irrigation and farming etc.

Applications
Mechanical flow control solution — BT-Maric flow controller

This is how it works

Why should you use constant flow valve restrictors?

Have you got the following challenges?

  • Do you need a constant and limited flow in your application?
  • Do you need a stable flow rate regardless of pressure of variations?
  • Do you need to control and minimize water flow rate?
  • Do you need to optimize water consumption in your system?
  • Do you need to protect your (centrifugal) pumps or filters?
  • Do you need to mix fluids in specific proportions? At high pressure? At low pressure?
  • Do you want to save water in hotels, restaurants, waterparks, condominium, campings by limiting flow rate at usage points?
  • Do you need to limit the water taking near the source within your irrigating system?
  • Is saving water a priority to you?

BT-Maric constant flow restrictors will help you to…

  • improve water flow or similar media in your process or product by always providing the chosen specified flow rate regardless of the pressure variations.
    Your system will thus have a stable, constant flow rate, if the pressure drop is within specified limits. It will prevent the break down or damage of your equipment and extend its life span. It will provide valuable protection for flow rate sensitive pumps, filters, pump glands, and water distribution “systems”.
  • reduce investment and flow-related operating costs by always providing the chosen specified fluid flow rate regardless of the pressure variations. Pressure variations often occur in systems with many points of“consumption”.
  • save water by limiting flow rate at usage points. Water is a vital and needs to be saved at all times.

Standard connections

The BT-Maric Constant Flow Valves are available
in 3 standard connections:

BT-Maric threaded constant flow valve for pipes from 1/8 to 2 inches
BT-Maric threaded constant flow valve – cut-away view showing internal O-rin

Easy to install

Threaded constant
flow valves

BT-Maric Threaded Constant Flow Valves are designed for pipes from 1/8″ up to 2″ and regulate flow rate from as low as 0,15 L/min up to 342 L/min.

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BT-Maric constant flow valve insert – compact design for existing pipework
BT-Maric constant flow valve insert shown fitted inside a pipe

Cost effective and compact!

Constant flow valve
type Inserts

BT-Maric Inserts are designed to be fitted inside existing pipe work or other equipments. They control flow rates up to 233 L/min.

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BT-Maric constant flow valve wafer type for installation between pipe flanges
BT-Maric wafer-type constant flow valve viewed from the flange side

For larger flow rates!

Constant flow valve
type Wafers

BT-Maric Wafers are designed to be placed between flange for pipe sizes between DN20 up to DN300. They control flow rates up to 8.854 L/min.

Find out more

How does BT-Maric flow limiters work?

This is how it works

BT-Maric constant flow valves utilize a flexible rubber control O-ring with an orifice diameter that responds instantly to fluctuations in water pressure.

As pressure differential increases, the orifice diameter reduces to maintain the pre-set flow rate.

Likewise, as pressure reduces, the orifice opens up to maintain the pre-set flow rate.

Watch our video:

A mechanical solution to achieve constant flow.

BT-Maric O-ring at low pressure – orifice opens wider to maintain constant flow

LOW PRESSURE

The ring has a larger opening at low pressure.

BT-Maric O-ring at high pressure – orifice narrows against the conical seat to maintain constant flow

HIGH PRESSURE

At high pressure the ring is pressed against the conical body. The ring’s opening reduces and the flow remains constant.

having questions?

Functionality of BT-Maric constant flow valves:

The BT-Maric flow control valve is designed to deliver a pre-determined constant flow rate of water and similar media regardless of pressure variations within a certain pressure range. The pressure range depends on the type of valve used.

The BT-Maric constant flow valve has an effect on the pressure, but is not designed to control the pressure in your system.
The control flow valve has no external actuation and is not adjustable after installation.
BT-Maric constant flow valves do not work with gas or air.

BT-Maric constant flow valves utilize a flexible rubber control O-ring with an orifice diameter that responds instantly to fluctuations of the pressure exerted. When the pressure increases the o-ring is pressed down in the conical seat and the orifice of the o-ring decreases in size in such a way that the flow remains constant at the pre-set nominal rate, and vice versa. In this way, the pre-set nominal flow rate is always kept constant regardless of the pressure variations.

Cross-section of BT-Maric screwed housing showing O-ring behaviour at high and low pressure

BT-Maric constant flow valves will help you:

  1. to reduce investment and operating flow-related costs by always providing the chosen specified flow rate regardless of the pressure variations. Pressure variations often occur in systems with many points of consumption.
  2. to improve the water flow or similar media in your process or product by always providing the chosen specified flow rate regardless of the pressure variations. Your system will thus have a stable, constant flow rate if the pressure drop is within specified limits. It will prevent the break down or damage of equipment. It will extend life span of your equipment. It will provide valuable protection for flow rate sensitive pumps, filters, pump glands, and water distribution systems.
  3. to save water by limiting the flow rate at usage points. Water is a vital natural resource and needs to be saved at all times.

No, only for water and similar liquids.

More FAQ

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