Flow Controls

various checked orifices and fixed flow controls

O’Keefe Controls Co. Flow Controls: Tamperproof Solutions for Precision Process Control

O’Keefe Controls offers three different types of flow controlling devices. Each of these flow controlling devices consists of an active component, like a check valve, and a passive component, like a precision orifice. How they are connected in relation to each other is what determines their performance characteristics.

The three types of Flow Controls manufactured by O’Keefe Controls Co. are the following:

  • Checked Orifices
  • Fixed Flow Controls
  • Bidirectional Fixed Flow Controls

Tamperproof Construction Ensures Consistency

Many flow control devices consist of an active component, such as a check valve, and a variable orifice set by a knob or a screw mechanism. This variable adjustment can be quite handy where field setting or frequent changes are required; however, in OEM applications where system parameters are well known and consistency and repeatability are valued, the adjustable aspect of the Flow Control can be undesirable.

A key feature of the flow controlling devices manufactured by O’Keefe Controls is their tamperproof construction. These Flow Controls do not contain any adjustment knobs or screws. We replace the variable orifice in our flow control products with a fixed precision orifice, making the device unalterable, or tamperproof.  This ensures that the flow characteristics of our Flow Controls are consistent and repeatable. Ideal for OEM applications where unwanted adjustments can negatively affect process performance, O’Keefe Controls Co. Flow Controls are a perfect solution.

Benefits of Our Flow Controls

Our Flow Controls are available in many materials and physical configurations.

Features include:

  • Multiple cracking pressure options
  • Long, trouble-free operation life
  • High pressure
  • High flow capacity
  • Low pressure loss

Checked Orifices

image of checked orifices

CLICK HERE to view our catalog of Checked Orifice offerings

Fixed Flow Controls

Fixed Flow Controls

CLICK HERE to view our catalog of Fixed Flow Controls offerings

Bidirectional Fixed Flow Controls

bidirectional fixed flow controls

CLICK HERE to view our catalog of Bidirectional Fixed Flow Controls offerings

Call us to ask about your Flow Controls application: 203.261.6711

image of checked orifices

Typical Applications of Checked Orifices

  • Unidirectional gas or liquid flow
  • Backflow prevention in metering systems
  • Fluid contamination reduction
  • Isolation of fluid sources in mixers
  • Fuel line metering with no reverse flow
  • Medical metering of fluids

CLICK HERE to view our catalog of Checked Orifice offerings

Checked Orifices

Checked Orifices consist of a check valve and a precision orifice in series. 

Incorporated in a single construction, the Checked Orifice allows metered flow in one direction and no flow in the opposite direction. Metered flow is achieved by a precision orifice while reverse flow is prevented by an integral check valve in series. Fluid flows first through the check valve mechanism in the free flow direction and is then metered by the precision orifice.

diagram of checked orifice, showing flow direction

Features of Checked Orifices

  • All-metal construction
  • Tamperproof
  • Long, trouble-free operating life
  • Available in NPT, UNF/UNC and threaded insert connections

Call us to ask about your Checked Orifices application: 203.261.6711

Fixed Flow Controls

Fixed Flow Controls are a check valve and a precision orifice in parallel.

Incorporated in a single fitting, the Fixed Flow Control allows metered flow in one direction and free flow in the opposite direction. Metered flow is achieved by a precision orifice and free flow is allowed by an opened check valve mechanism in the opposite direction along with the contribution of the precision orifice. Free flow is defined as the combined flow capacity of the check valve mechanism and precision orifice.

diagram of a Fixed Flow Control

Typical Applications of Fixed Flow Controls

  • Air cylinder speed controls
  • Compressed air dryer purge controls
  • Timing circuits
Fixed Flow Controls

Features of Fixed Flow Controls

  • All-metal construction
  • Long, trouble-free operating life
  • Many cracking pressure options
  • Tamperproof
  • High pressure
  • High flow capacity
  • Low pressure loss

CLICK HERE to view our catalog of Fixed Flow Controls offerings

Call us to ask about your Fixed Flow Controls application: 203.261.6711

bidirectional fixed flow controls

Features of Bidirectional Fixed Flow Controls

  • All-metal construction
  • Long, trouble-free operating life
  • Many cracking pressure options
  • Tamperproof
  • High pressure
  • High flow capacity
  • Low pressure loss

CLICK HERE to view our catalog of Bidirectional Fixed Flow Controls  offerings

Bidirectional Fixed Flow Controls

Bidirectional Fixed Flow Controls are a checked orifice and a precision orifice in parallel.

Incorporated in a single construction, the Bidirectional Fixed Flow Control allows metered flow in one direction and a separate metered free flow in the opposite direction. Metered flow is achieved by a precision orifice within the checked orifice portion and metered flow in the opposite direction is achieved by a separate precision orifice.

Diagram of Bidirectional Fixed Flow Control

Typical Applications of Bidirectional Fixed Flow Controls

  • Speed control of spring-loaded cylinders
  • 3-way valve dampening

Call us to ask about your Bidirectional Fixed Flow Controls application: 203.261.6711

Industrial Applications for Flow Controls

dispensing yogurt into cups on automated production line

Checked Orifices allow metering out a specific amount of a substance with no drips or back flow.

plasma cutting technology

Useful in plasma cutting  technology, Checked Orifices allow mixing precise quantities of different working gases from isolated sources.

boxes on conveyor belt in warehouse

Fixed Flow Controls can be employed to regulate movement of product on conveyors without risking damage.

industrial desiccant dryers

Fixed Flow Controls are ideal for use in regenerative desiccant drying systems.

pneumatic cylinders on automated machinery

Use of Bidirectional Fixed Flow Controls allows one device to control both the extension and retraction rates for spring-return cylinders. 

Checked Orifices

Liquid dispensing is a common application for a Checked Orifice. The device allows a metered flow in one direction to dispense the fluid, while back flow or dripping is prevented by the check valve mechanism when the source is shut off.  A Checked Orifice’s flow characteristics are also useful when the process demands metering out a very specific amount of a substance and the accuracy and portions are critical. While this functionality can be achieved using a combination of other valves, having two metering devices in one body offers a distinct advantage in terms of simplification of design, as well as maintenance.

Additionally, mixing of liquids or gases with fluid source isolation can be achieved by using multiple Checked Orifices connected in parallel.

Fixed Flow Controls

Speed Control – Controlling the rate at which an actuator moves is crucial to optimum operation of pneumatic machinery.  A common example is controlling a double-acting pneumatic cylinder. Simply put, pressurized fluid enters a port in the cylinder causing extension of the rod and at the same time allows the opposite cylinder port to vent. The opposite pressure and vent condition causes cylinder rod retraction. Control of the speed of extension and retraction of the cylinder rod is achieved using Fixed Flow Controls which can allow free flow into the extend and retract ports while restricting the exhaust rates. In this example, two Fixed Flow Controls are required, one for each cylinder rod direction.

Time delay – In automated processes, the timing of certain actions can be critical. Timing allows for sequences to complete before the next step, or to start only after certain conditions have been met. Thus, time delay is another use of the Fixed Flow Control. A Fixed Flow Control in series with a volume can provide a time delay on startup of a pneumatic circuit, or as the circuit is depressurized. On-delays or off-delays can be used to prevent immediate change in state in pressurized circuits.

Process control can also be achieved by use of Fixed Flow Controls, such as in desiccant air dryers. A typical system consists of two towers, one for drying the air and the other for regenerating the desiccant. The drying tower contains a porous desiccant material that adsorbs water molecules as compressed air from the inlet passes over it. To regenerate the desiccant material, a small portion of dried air is expanded and blown over the desiccant bed in the offline tower. The water vapor is exhausted out. 

Ideal for this type of operation., the Fixed Flow Control allows free flow through the drying tower in the forward direction and metered flow in the reverse or purging direction. O’Keefe Controls Co. manufactures Fixed Flow Controls in a wide choice of sizes and connections, allowing us to handle applications from large dryers in factory settings to small appliances employed for point-of-use dry air, requiring sub-miniature Fixed Flow Controls.   

Bidirectional Fixed Flow Controls

Applications for Bidirectional Fixed Flow Controls are similar to those of Fixed Flow Controls. However, the Bidirectional Fixed Flow Control’s feature of flow metering in both directions offers a distinct advantage for specific applications. What is known as free flow in a Fixed Flow Control is replaced by a metered flow, allowing precise fluid control in both directions. This can be helpful in dampening using a three-way valve as a pressure source.

Speed control of a single acting, spring return cylinder using a single Fixed Flow Control may cause excessive speed in the free flow direction, resulting in unwanted slamming. The addition of a second Fixed Flow Control in series can eliminate the slamming but at additional cost and space. Instead, the installation can be simplified using a Bidirectional Fixed Flow Control. Proper selection of forward and reverse flow capacities will keep actuation rates within desired times.

Have questions regarding your Flow Control application? Call 203.261.6711

The Vital Role of Tamperproof Flow Controls in Industrial Automation white paper

Download our white paper posted on the Resources page for a more detailed look at the advantages of Tamperproof Flow Controls in Industry.

The Vital Role of Tamperproof Flow Controls in Industrial Automation

Whether you’re boxing orders at a warehouse and moving them down the assembly line, dispensing exact quantities of yogurt into containers in a dairy factory, or controlling the speed of metal-stamping machinery, Flow Controls play a key role in keeping automated processes moving without worry. As differing processes have unique requirements in how motion is controlled, various flow controls, each with specific characteristics, have been developed to answer the challenges among industrial applications.

Our whitepaper explores the three types of Flow Controls offered by O’Keefe Controls Co. and the crucial role they play in automated processes. Once process speed and timing is established to maximum efficiency with minimum waste, these inherently tamperproof devices ensure those controls remain constant. Manufactured to standards of unsurpassed accuracy and repeatability, utilizing O’Keefe Controls Co. Flow Controls helps reduce machinery wear and tear, automation breakdowns, loss of product and overall cost of operation.

Call us to get your technical questions answered: 203.261.6711

Used Worldwide for Tamperproof Flow Control

Flow Controls manufactured by O’Keefe Controls Co. are designed to ensure tamperproof operation with accurate, repeatable flow characteristics. This enables us to help industries across the world achieve the exact flow control required in their processes. Our Flow Controls pass stringent quality control testing to ensure they operate exactly as specified, with consistent performance. 

With a quality management system that is ISO 9001:2015 registered, all processes are held to the highest standards of quality. But perhaps of even greater benefit to our customers, the engineers at O’Keefe Controls Co. are technical experts in the field — knowledgeable about not only our products, but also the science behind their use. As such, we are able to assist customers in diverse practical applications across the industrial, analytical and medical sciences landscape. In all we do, we stand proudly by our tagline: If it’s about precision, it’s O’Keefe.