Samson Type 46-6 Differential Pressure Regulator with Flow Limit

Samson Type 46-6 differential pressure regulator with flow limitation

The Samson Type 46-6, built from the Type 2466 valve and actuator, is a self-operated differential pressure regulator with an adjustable flow limiter. It belongs to Series 46 and closes when the differential pressure rises, so it holds a constant pressure drop across a plant section and caps the flow at a set maximum. The datasheet gives valve sizes DN 15 to 50, PN 16 and PN 25, liquids up to 150 °C and gases up to 80 °C. Seven Star LLC supplies the Type 46-6 in Oman and the GCC as an independent supplier in Muscat, mainly for chilled-water, hot-water and district energy installations where no auxiliary power is available at the regulator.

The 46-6 is the adjustable version of a pair. The Type 46-5 (Type 2465) in the same datasheet has a fixed differential pressure set point of 0.2, 0.3, 0.4 or 0.5 bar; the Type 46-6 lets the user set the differential pressure on a screw or manual adjuster. Both types share the same valve body, restriction and operating principle.

Type 46-6 versus Type 46-5 and related codes

Type 46-6 technical specifications

How the Type 46-6 works

Medium flows in the direction of the arrow. The areas released by the restriction and by the valve plug together determine the flow and the differential pressure. The high pressure of the plant is led to the bottom diaphragm chamber, and the pressure downstream of the restriction acts from above through a hole in the plug. The resulting differential is converted to a force that moves the plug against the set point spring. When the flow limit is reached the plug throttles so that the pressure drop at the restriction equals the pressure drop that corresponds to the maximum flow. Only one control line is required, which keeps the installation cost low.

Choosing the set point and flow limit

The differential pressure set point is the sum of the plant pressure drop when fully open and the pressure drop across the restriction. As a rule of thumb the datasheet assumes 0.2 bar across the restriction. The minimum differential pressure between flow and return pipes is calculated from the set point plus the flow-dependent term (flow divided by KVS, squared). Table 3 of the datasheet lists the achievable flow range for each DN and KVS at 0.1 and 0.2 bar across the restriction; a noise increase is expected when these flow rates are exceeded even without cavitation.

Where the 46-6 fits in a system

The regulator is installed in the return line, for example in a building substation, a chilled-water branch or an industrial heating loop, and it makes each branch independent of the others. It is related to the Samson 45-1 N differential pressure regulator and 42-36 flow regulator already on this site, and with the Type 47-5 which combines flow and differential pressure control.

Selection checklist for a Type 46-6

• Maximum flow to be limited, and the plant pressure drop at that flow.
• Required differential pressure set point or range (0.2 to 1, 0.5 to 2 or 1 to 4 bar).
• DN, KVS and the pressure rating needed for the line.
• Medium and temperature; special FKM seals for oils.
• End connection: welding ends, threaded ends, flanges or a flanged body for DN 32 to 50.
• A strainer upstream, for example a Type 1 NI, to protect the seat.

Installation, commissioning and maintenance of the 46-6

The regulator can be installed in horizontal or vertical pipes, but DN 32 and larger must go in horizontal lines with the actuator facing down. Respect the flow arrow, connect the external control line to the high-pressure pipe at the side or top, and fit a strainer where practical. Set the flow limit at the cover cap on the restriction and adjust the differential pressure at the set point adjuster while a stable flow is running. Maintenance is low because no auxiliary energy is used; the EPDM diaphragm and seats should be inspected during system shutdowns.

Typical applications of the Type 46-6 in Oman and the GCC

Self-operated differential pressure regulators suit district cooling energy transfer stations, chilled-water risers in large buildings, hot-water heating at industrial camps and process utility loops. Because the regulator needs no power or air, it is practical at remote camps and utility skids where reliability matters more than the ability to change set points remotely.

Information to send with your Type 46-6 RFQ

• Medium, temperature range and operating pressure.
• Maximum flow to be limited and the pressure drop of the fully opened plant.
• Required differential pressure set point.
• DN, pressure rating and connection type.
• Any need for FKM or other special seals.
• Quantity, tag list and delivery site.

Documents and quotation

The Samson data sheet T 3130 covering the Type 46-5 and Type 46-6 is attached on this page. Send the duty data and we will confirm availability and lead time. Seven Star LLC is an independent supplier and does not claim any official status with the manufacturer.