Emerson FL User manual

Bulletin 71.2	Type FL
D103067X012
August 2020

Type FL Pressure Reducing Regulators

Features

•No Atmospheric Bleed—Eliminates nuisance and wasteful bleed gas to atmosphere by utilizing a self-contained control system, which bleeds 100% of the gas to the downstream system.

•Quiet Operation—Multiple noise attenuation options available which reduce noise by up to 25 dBa at

the source, eliminating the need for expensive path treatments such as insulation, buried valves and enclosures which only mask noise.

•High Capacity—The highly efficient axial flow design produces exceptionally high capacities.

•Long Life in Severe Service Applications—The metal plug design deflects particles and debris away from the soft-seat, which gives excellent particle erosion resistance.

•Precise Pressure Control—Provides accurate downstream pressure control regardless of inlet pressure variations or demand changes.

•Easy In-Line Maintenance—Outlet flange spacer allows trim parts such as the disk holder to be inspected, cleaned and replaced without removing the body from the pipeline.

•Bubble-Tight Shutoff—A knife-edged metal plug and soft seat provide bubble tight shutoff for use in applications where positive shutoff is required such as dead-end systems.

•Full Pressure Rating—The equal inlet and outlet pressure rating of 1480 psig / 100 bar, which allows easier selection and requires no special startup or shutdown procedures.

•Versatility—Ideal for a wide variety of applications such as natural gas transmission and distribution stations and power plant feeds.

•Travel Indicator—Simplifies in-service inspection and system troubleshooting.

•High Turn Down Capability—The oversized diaphragm and unique piloting system allow for high turn down, providing superior pressure control in systems with large variations in downstream flow demand.

Figure 1. Type FL Regulator with Type PRX Pilot

•Disk Design—The FL series offers disks for the main body made from Nitrile (NBR), Fluorocarbon (FKM), and Polyurethane (PU). Polyurethane (PU) provides better abrasion

resistance properties and a high durometer rating to extend the working life of the disk in difficult applications such as high pressure drop and

low flow.

Introduction

The Type FL is an accurate, pilot-operated regulator designed for high-pressure transmission/city gate, large capacity distribution systems and power plant feeds. Type FL provides smooth and quiet operation, tight shutoff and long service life. The regulator is comprised of a main valve actuator, a Type PRX pressure reducing pilot and a Type SA/2 pilot supply pressure regulator.

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Type FL

Specifications

The Specifications section gives some general specifications for the Type FL regulators. The nameplates give detailed information for a particular regulator as it comes from the factory.

Available Configuration

Type FL: Pilot-operated pressure reducing regulator from 14.5 to 1160 psig / 1.00 to 80.0 bar outlet pressures

Body Sizes

Type FL: NPS 1, 2, 3, 4, 6, 8 and 10 /

DN 25, 50, 80, 100, 150, 200 and 250

Type FL with Type SRS Silencer (Inlet x Outlet):

NPS 1 x 4, 2 x 6, 3 x 10, 4 x 10, 6 x 12 and 8 x 16 / DN 25 x 100, 50 x 150, 80 x 250, 100 x 250,

150 x 300 and 200 x 400

Main Valve End Connection Style and Pressure Ratings(1)

CL300 RF: 740 psig / 51.0 bar(3) CL600 RF: 1480 psig / 102 bar(3)

Maximum Inlet and Outlet (Casing) Pressure(1)

1480 psig / 102 bar(3)

Minimum Operating Differential Pressure

Start Open:

NPS 1 to 4 / DN 25 to 100: 7.3 psid / 0.50 bar d NPS 6 and 8 / DN 150 and 200: 3 psid / 0.21 bar d

NPS 10 / DN 250: 2.9 psid / 0.2 bar d

Full Open

NPS 1 to 4 / DN 25 to 100: 14.5 psid / 1.00 bar d NPS 6 and 8 / DN 150 and 200: 7.3 psid /

0.50 bar d

NPS 10 / DN 250: 8.7 psid / 0.6 bar d

Outlet (Control) Pressure Ranges

See Table 1

Flow and Coefficients

See Table 2

Pilot and Filter-Regulator Flow Coefficients

Type PRX Pilot: Cg: 10.5; Cv: 0.36; C1: 29

Type SA/2 Filter-Regulator: Cg: 19

Pressure Registration

External

Process Temperature Capabilities(1)(2)

Nitrile (NBR), Fluorocarbon (FKM) or Polyurethane (PU) Disk

ANSI/FCI 70-3 Class VIII: -4 to 140°F / -20 to 60°C

Nitrile (NBR) or Polyurethane (PU) Disk

ANSI/FCI 70-3 Class VI: -20 to 140°F / -29 to 60°C

Approximate Weights (Including Pilot)

See Figure 7

Construction Materials Type FL Main Valve

Main Body and Flanges: Steel

Sleeve and Disk Holder: Steel Diaphragm Plates: Steel

Diaphragm: Nitrile (NBR) with PVC coating

Disk O-rings: Nitrile (NBR) or Fluorocarbon (FKM) Disk: Nitrile (NBR), Fluorocarbon (FKM)

or Polyurethane (PU)

Type PRX Pilot

Body: Steel

Trim: Stainless steel

Diaphragm: Nitrile (NBR) or Fluorocarbon (FKM) Disk O-rings: Nitrile (NBR) or Fluorocarbon (FKM) Disk: Polyurethane (PU) or Fluorocarbon (FKM)

Type SA/2 Supply Pressure Regulator

Body: Steel

Diaphragm: Nitrile (NBR) with PVC Coating O-rings: Nitrile (NBR) or Fluorocarbon (FKM) Disk: Polyurethane (PU) or Fluorocarbon (FKM)

1.The pressure/temperature limits in this Bulletin and any applicable standard or code limitation should not be exceeded.

2.Types PRX and SA/2 Fluorocarbon (FKM) elastomer are limited to 0°F / -18°C.

3.At average ambient temperature.

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Type FL

E0822

TYPE SR

TYPE SRII

TYPE SRS

Figure 2. Noise Abatement Construction

	110
	100
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	80
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	70
	60					STANDARD
						TYPE SR OR SRII
						TYPE SRS

50
0			187,567 /	373,134	/	559,701	/	746,269	/
			5000	10,000		15,000		20,000

FLOW RATE IN SCFH / Nm3/h

Figure 3. Typical Sound Emission Comparison among the Different Configurations

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Type FL

The regulator’s superior performance is due to the amplifying effect of the pilot and two-path control system. Changes in outlet pressure act quickly on the actuator diaphragm to provide fast response to system change.

Then the pilot amplifies any small system changes to position the main valve for precise pressure control.

Type PRX Pilot Descriptions

The Type FL pressure reducing regulators include a PRX Series pilot mounted on the main valve.

Type PRX/120: Outlet pressure range of 14.5 to 435 psig / 1.00 to 30.0 bar. Type PRX/120 can be used as the pilot on single stage pressure-reducing

regulators, as the monitor or working pilot in wide-open monitor systems or as the working pilots in working monitor systems.

Type PRX/120-AP: Outlet pressure range of 435 to 1160 psig / 30.0 to 80.0 bar. The Type PRX/120-AP can be used as the pilot on single stage pressurereducing regulators, as the monitor or working pilot in wide-open monitor systems or as the working pilots in working monitor systems.

Type PRX/125: This pilot is identical to the

Type PRX/120 except that the restriction screw is removed. Type PRX/125 can only be used as the monitor override pilot on working monitor applications.

Type PRX/125-AP: Identical to the Type PRX/120-AP except that the restriction screw is removed.

Type PRX/125-AP can only be used as the monitor override pilot on working monitor applications.

Type PRX/131: Outlet pressure range of 14.5 to

435 psig / 1 to 30 bar. The Type PRX/131 is used as a booster or quick dump pilot on a single stage pressure reducing regulator or with the monitor pilot on the monitor regulator in Wide-Open Monitor systems. It

is installed as standard on the regulator for NPS 10 / DN 250 and can be used on any other size to increase its closing speed.

Type PRX/131-AP: Outlet pressure range of 435 to 1160 psig / 30 to 80 bar. This pilot is used as a

booster or quick dump pilot on a single stage pressure reducing regulator or with a monitor pilot on the monitor regulator in Wide-Open Monitor systems.

Type SA/2 Pilot Supply Filter Regulator

The PRX Series pilots are usually used together with the Type SA/2 pilot supply filter regulator. The

Type SA/2 acts as a pressure stabilizer that provides a constant supply pressure to the PRX Series pilots: that is approximately 45 psi / 3.1 bar over set pressure.

Type SA/2 has an integral 5 micron filter. This integral filter acts only as an emergency filter; gas must be cleaned upstream of the regulator.

Noise Abatement

At elevated pressure drops and flow rates, regulators with standard trims can produce unacceptable noise levels. Several options are available to reduce the noise generated.

Type SR: Type SR (Figure 2) multi-path noise abatement device is incorporated into the regulator on the seat area. It consists of plated Stainless steel wires containing no sound deadening materials.

Depending on flows and pressure drop, the silencer can reduce noise levels as much as 20 dB (A) with an approximate 3% Cg reduction. Type SR is available only in NPS 1 through 6 / DN 25 through 150 and is not recommended for high velocity applications.

Type SRII: The Type SRII (Figure 2) noise abatement device is the next generation of Type SR and is

used in case of extreme service conditions (dirty gas, high pressure drops and high gas velocities). Noise characteristics are very similar to the standard Type SR.

Type SRS: A second noise reduction device may be added to the Type FL regulators. Type SRS (Figure 2) consists of a Type SR or SRII plus a widened outlet flange in which a second silencer is fitted. Noise reduction is based on the principle of stream splitting and gradual expansion in several stages. By using a wider outlet flange the silencer can be mounted integral to the regulator body which allows installation of the regulator directly into the downstream piping without an expansion joint. Noise reduction up to 25 dB (A)

is reached without limiting the velocity in the outlet flange with a Cg reduction of about 15%. Type SR/SRS Silencer is available only in NPS 1 through 6 / DN 25 through 150.

Principle of Operation

The pilot-operated Type FL (Figure 4) uses inlet pressure as the operating medium, which is reduced through pilot operation to load the actuator diaphragm. Outlet pressure opposes loading pressure in the actuator and also opposes the pilot control spring.

When outlet pressure drops below the setting of the pilot control spring, pilot control spring force on the pilot diaphragm opens the pilot valve plug, providing additional loading pressure to the actuator diaphragm.

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Type FL

TYPE

SA/2

M

R

B

V

TYPE

PRX/120

L

8 TO 10

PIPE

DIAMETER

TYPE FL

E0827_01/2016

INLET PRESSURE

OUTLET PRESSURE

ATMOSPHERIC PRESSURE

LOADING PRESSURE

PILOT SUPPLY PRESSURE

Figure 4. Type FL Operational Schematic

Table 1. Outlet (Control) Pressure Ranges

	OUTLET PRESSURE RANGE		AC		PILOT CONTROL SPRING INFORMATION
TYPE	psig	bar	(ACCURACY	Spring Color	Part Number	Wire Diameter				Free Length
			CLASS)
						In.	cm		In.		cm
	14.5 to 26	1.00 to 1.8	2.5%	Yellow	M0255240X12	0.110	0.28
	23 to 44	1.6 to 3.0	2.5%	Green	M0255230X12	0.126	0.32		2.16		5.49
PRX/120	41 to 80	2.8 to 5.5	2.5%	Blue	M0255180X12	0.138	0.35
	73 to 123	5.0 to 8.5	2.5%	Black	M0255220X12	0.157	0.40
PRX/125
PRX/131	116 to 210	8.0 to 14.5	1%	Silver	M0255210X12	0.177	0.45		2.16		5.49
	203 to 334	14.0 to 23.0	1%	Gold	M0255200X12	0.197	0.50		2.00		5.10
	319 to 435	22.0 to 30.0	1%	Aluminum	M0255860X12	0.236	0.60		2.00		5.10
PRX-AP/120
PRX-AP/125	435 to 1160	30.0 to 80.0	1%	Clear	M0273790X12	0.335	0.85		3.93		10.0
PRX-AP/131

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Type FL

TYPE

PRX/120

TYPE

SA/2

M

		S
	R
		B
	V	L
		A

TYPE

PRX/120 TYPE

SA/2

M

		S
	R
		B
	V	L
		A

	M1204_01/2016	8 TO 10
		PIPE
		DIAMETER

TYPE FL WIDE-OPEN MONITOR

	TYPE
	PRX/125
	TYPE
	SA/2
	M
		S
	R
	B	L
	V
		A

TYPE

PRX/120

S

B

L

A

	TYPE		TYPE
			PRX/120
M	SA/2
			S
		R
			B
		V	L
			A

M1201_01/2016

8 TO 10

8 TO 10

INLET PRESSURE

PIPE

PIPE

OUTLET PRESSURE

DIAMETER

DIAMETER

ATMOSPHERIC PRESSURE

LOADING PRESSURE

INTERMEDIATE PRESSURE

PILOT SUPPLY PRESSURE

TYPE FL WORKING MONITOR WITH TYPE PRX-125

Figure 5. Typical FL Installation Schematics

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Type FL

TYPE

SA/2

M

R

V

TYPE
PRX/120
		TYPE
		PRX/131
S	S	B
B	L
L
A		A

8 TO 10

PIPE

DIAMETER

M1216_01/2016

TYPE FL WITH TYPE PRX/131 QUICK DUMP PILOT

TYPE

PRX/120

TYPE

SA/2

M

S

R

B

L

V

A

	TYPE
	PRX/131
S	B
L
	A

TYPE		TYPE
		PRX/120
SA/2
M
		S
	R
		B
		L
	V	A

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	8 TO 10
	PIPE
M1212_01/2016	DIAMETER
INLET PRESSURE
OUTLET PRESSURE
ATMOSPHERIC PRESSURE
LOADING PRESSURE
INTERMEDIATE PRESSURE
PILOT SUPPLY PRESSURE

TYPE FL WIDE-OPEN MONITOR WITH TYPE PRX/131 QUICK DUMP PILOT

Figure 5. Typical FL Installation Schematics (continued)

7

Type FL

This diaphragm loading pressure opens the main valve plug, supplying the required flow to the downstream system. Any excess loading pressure on the actuator diaphragm escapes downstream through the exhaust restriction in the pilot.

When the gas demand in the downstream system has been satisfied, the outlet pressure increases.

The increased pressure is transmitted through the downstream control line and acts on the pilot diaphragm. This pressure exceeds the pilot spring

setting and moves the diaphragm, closing the orifice.

The loading pressure acting on the main diaphragm bleeds to the downstream system through the exhaust restriction in the pilot.

Installation

Type FL regulators are installed in a horizontal or vertical pipeline. An optional outlet flange spacer

(Figure 6, page 8) is available to be installed downstream of the regulator. Once the spacer and outlet flange are removed, the disk holder and trim parts are easily accessed. See Figure 5 for typical piping installations. Dimensions are given in Figure 7.

Type FL may be installed in any position, but is normally installed in a horizontal pipeline with the pilot or pilots above the body. The optimal location for the sense and bleed lines is between the Type FL and the downstream block valve. If the sense and bleed lines cannot be located between the Type FL and downstream block valve, contact your local Sales

Office for Startup assistance. See Figure 5 for typical piping installation.

Note

To prevent damage to the pilot during Startup, the sense and bleed lines should be located on the same side of the downstream block valve.

Monitoring Systems

Monitoring regulation is overpressure protection by containment, therefore, there is no relief valve to vent to the atmosphere. When the working regulator fails to control the pressure, a monitor regulator installed in series goes into operation to maintain the downstream

pressure at a higher value than normal pressure. During an overpressure situation, monitoring keeps the customer online. Also, testing is relatively easy and safe. To perform a periodic test on a monitoring regulator, increase the outlet set pressure of the working regulator and watch the outlet pressure to determine if the monitoring regulator takes over at the appropriate outlet pressure.

Wide-Open Monitoring Systems (Figure 5)

There are two types of wide-open monitoring systems: upstream and downstream. The difference between upstream and downstream monitoring is that the functions of the regulators (monitor and worker) are reversed. Systems can be changed from upstream

to downstream monitoring and vice-versa, by simply reversing the setpoints of the two regulators. The decision to use either an upstream or downstream monitoring system is largely a matter of personal preference or company policy.

In normal operation of a wide-open configuration, the working regulator controls the system’s outlet pressure. With a higher outlet pressure setting, the monitor regulator senses a pressure lower than its setpoint and tries to increase outlet pressure by going

wide open. If the working regulator fails, the monitoring regulator assumes control and holds the outlet pressure at its outlet pressure setting.

Working Monitoring Regulators (Figure 5)

In a working monitoring system, the upstream regulator requires two pilots and it is always the monitoring regulator. The additional pilot permits the monitoring regulator to act as a series regulator to control an intermediate pressure during normal operation.

In this way, both units are always operating and can be easily checked for proper operation.

In normal operation, the working regulator controls the outlet pressure of the system. The monitoring regulator’s working pilot controls the intermediate pressure and the monitoring pilot senses the system’s outlet pressure. If the working regulator fails, the monitoring pilot will sense the increase in outlet pressure and take control.

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