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PT CONTROMATIC PRIMA MANDIRI

REGULATORS

Regulator

Operation

Their operation is similar to control valve but they are different devices and obey to different rules and this has to be kept in consideration:

Pressure regulators control pressure; they do NOT regulate flow.

Flow rate and controlled pressure are linked together; thus, change flow – change in pressure

Controlled pressure varies with flow. The amount of variation in controlled pressure with a given change in flow is called: Proportional

Band: Droop/Offset [Reducers] Build/Accumulation [Back Pressure/Relief]

Regulators are best used in systems where flow changes are small.

Regulators are NOT shut off devices.

DO NOT hydrostatically test a regulator

Reducing regulators, in most cases, have two separate pressure/temperature ratings for the inlet and outlet.

Regulators DO NOT fail in the most frequently desired modes.

Regulators are devices whose main function is to match the flow of the medium (gas, steam or liquid) through the regulator to the demand of the

medium by the system. At the same time the regulator must maintain the system pressure at a requested pressure, or within an acceptable range

of this pressure. Regulators, in general, are very simple devices, they are simpler devices than control valves, and experience in general teaches

us that the simpler a system is, the more reliable it is, as long as it provides a control within the requested limits. Regulators are self-contained,

self-operated control devices which use energy from the controlled system to operate. They do not require any external resource like: power

sources, transmitting instruments, external air or hydraulic supply. Carraro, since 1924, produces a wide range of regulators covering the most

typical applications in the air, steam, process gasses and liquids applications. It also supplies tailor made products for specific applications like

gas and steam turbine auxiliary systems (lubricating systems and air or hydraulic sealing systems) and tank blanketing & vapour recovery system

for storage tanks.

Why use regulators ?

Control Valve application (example) Regulator application (example)

Feedback Signal

Supply

Controller

SupplyPC

50PSIGTANK

50PSIGTANK

Pressure Regulator

On the last section of this catalogue you will find an introduction to the theory of regulators, describing the principles of operation and some

terminology like “offset” or “droop” very important in the correct sizing and selection of regulators

There are many reasons for using regulators instead of other more sophisticated devices. As long as the regulator the requested service

the more relevant reasons for choosing regulators are list below :

In general engineers, agree that simpler a device is, the more reliable it is. Every component has a probability of failure and the failure

probability of a system is the sum of all failure probabilities of its components. The fewer and simpler the components, the lower the

failure probability.

As regulators are simpler than control valves, they also less expensive, and require simple maintenance and therefore low servicing

costs.

Regulators are self-contained and self-operated control devices. they don't need any type of external power supply, transmitting

instruments on control instruments, which make them very suitable to be installed in very critical environments where no power source

can be matched.


Regulators operations

A pressure reducing regulator maintains a desired downstream pressure while providing the required flow to satisfy the load or user demand. This

pressure maintained by the regulator is the outlet pressure setting (setpoint) of the regulator. In general, as the outlet pressure changes with the

variation of the flow demand, the downstream pressure setting is referred to as the downstream pressure when the regulator is supplying the

standard flow requested in the most common operating conditions. Direct-operated regulators are the simplest devices available for downstream

pressure control. They are available with internal or external pressure sensing and can have a flow to open or flow to close design. Direct-

operated pressure reducing regulators can be designed only with a spring to open layout so the only possible failure modes are:

Spring failure : Regulator Close

Diaphragm : Regulator Open

A pressure relief valve prevents overpressure in a pressure system. The relief valve opens relieving the excess fluid so to prevent a rise of

pressure over a desired limit. The pressure at which the relief valve begins to open is the relief pressure setting. Relief valves and backpressure

regulators are the same devices. The type of application determines the name. Relief valves work closed opening only in case of excess

pressure, while backpressure regulators work open modulating the flow. Relief valves are NOT safety valves. Direct-operated relief valves and

back pressure regulators can be designed only with a spring to close layout so the only possible failure mode are:

Spring failure : Regulator Open

Diaphragm : Regulator Close

A backpressure regulator maintains a desired upstream pressure by varying the flow in response to changes in upstream pressure. The

upstream pressure maintained by the regulator is the pressure setting (setpoint) of the regulator. In general, changes in the flow cause variation in

the inlet pressure, the upstream pressure setting is referred to as the upstream pressure the regulator has to maintain during standard operating

flow conditions. Direct-operated back pressure regulators are available with internal or external pressure sensing and are limited to flow to close

design. Flow to open design can be supplied only for special requests.

A differential pressure reducing regulator maintains a desired downstream pressure with respect to a reference pressure other than the

atmospheric while providing the required flow to satisfy the load or user demand. A differential pressure backpressure regulator maintains a

desired upstream pressure with respect to a reference pressure other than atmospheric by varying the flow in response to changes in upstream

pressure. According to the two descriptions given above the two type of regulators operate as the regulators described previously, but instead of

having as reference the atmospheric pressure they can reference their set pressure to the pressure in a vessel or in a pipe. This pressure

maintained by the regulator is the setting (setpoint) of the regulator, and it is relative to the reference pressure, it is NOT a gauge pressure as

Vacuum breakers are valves that limit the increase in vacuum. An increase in vacuum (decrease in absolute pressure) beyond the setpoint

causes the valve to open permitting the higher pressure to enter the system and restoring the controlled vacuum within its desired limits .

REGULATORS

Pressure reducing regulators

Pressure relief valves

Back Pressure Regulators

Differential Pressure Regulators

Vacuum-breaking valves


REGULATORS

UBAN - Direct operated pressure reducing valve

FUNCTION : Relief / Backpressure

DIAMETERS : From 1/2” up to 2”

CONNECTIONS : Threaded (F-NPT

or GAS/BS) Flanged (ANSI or PN)

SEAT : Single

MAX RATING : ANSI 600

CV : From 0,031 up to 35

BODY MATERIAL : Carbon Steel,

Stainless steel, “ Exotic Materials”

TRIM MATERIAL : Stainless steel

(std), “ Exotic Materials”

DIAPHRAGMS : Polychloroprene,

EPDM, FKM, Stainless steel, other

MAX INLET PRESSURE : 52 barg

REGULATED PRESSURE RANGE :

0,0012 - 52 barg

MIN / MAX TEMPERATURE :

-196°C / 300°C

UBS - Direct operated pressure relief / backpressure valve

FUNCTION : Reducing


CONNECTIONS : Threaded (F-NPT or

GAS/BS) Flanged (ANSI or PN)

SEAT : Single


CV : From 0,031 up to 12,8



TRIM MATERIAL : Stainless steel (std),

“ Exotic Materials”




(threaded version up to 1”)


0,0012 - 52 barg


-196°C / 300°C

UBR - High Capacity direct operated pressure reducing valve

FUNCTION : Reducing


CONNECTIONS : Flanged (ANSI or

PN)

SEAT : Single


CV : From 1 up to 52,6







MAX INLET PRESSURE : 103.4 barg

(rating Class 600)


0,0012 - 52 barg


-196°C / 300°C

FUNCTION : Reducing / Relief /

Backpressure

DIAMETERS : From 1/2” up to 1 1/2”


or GAS/BS)

SEAT : Single


CV : From 0,04 up to 4,95


Stainless steel


(std)

DIAPHRAGMS : NBR



3,4 - 610 mbarg


-25°C / 90°C

UBB - Direct operated pressure reducing / relief valve

UBAS HP - Direct operated pressure relief valve

FUNCTION : Relief

DIAMETERS : From 1/4” up to 1/2”


or GAS/BS)

SEAT : Single



BODY MATERIAL : Stainless steel


(std)

DIAPHRAGMS : PTFE, Stainless

steel



0,35 - 5,8 barg


-196°C / 250°C

FUNCTION : Reducing / Relief



NPPN)

SEAT : Single / Double









MAX INLET PRESSURE : 103,4 barg

(rating Class 600)


0,015 - 20 barg


-35°C / 540°C

M51 - Direct operated, weight and lever pressure regulators


REGULATORS

MM - Direct operated, Spring pressure regulators

FUNCTION : Reducing/ Relief /

Backpressure


CONNECTIONS : Flanged (ANSI or PN)






TRIM MATERIAL : Stainless steel (std), “

Exotic Materials”


EPDM, EPDM, FKM, other

MAX INLET PRESSURE : 103,4 barg

(rating Class 600)


0,0012 - 30,7 barg


-50°C / 200°C

BPM - Direct operated, spring pressure regulators

FUNCTION : Reducing / Relief /

Backpressure


CONNECTIONS : Flanged (ANSI or PN)






TRIM MATERIAL : Stainless steel (std), “

Exotic Materials”


EPDM, FKM, other


(rating Class 1500)


0,08 - 30.7 barg


-50°C / 540°C

MAXOMATIC - Multifuction pilot-operated regulators for liquids

FUNCTION : Reducing / relief / flow

limitation / level regulation



or GAS/BS) Flanged (ANSI or PN)

SEAT : Single


CV : From 75 up to 1460


“Exotic Materials”

DIAPHRAGMS : NR, NBR, FKM

MAX INLET PRESSURE : 20 bar


0,5 - 16 barg


-10°C / 150°C

PILOT CIRCUIT : Copper, Stainless

Steel, “exotic” materials

FUNCTION : 2 ways : temp. control /

3 ways : deviating - mixing


CONNECTIONS : Flanged (ANSI /

PN / DIN)





Stainless steel


(std)

REGULATED TEMPERATURE

RANGE : -25°C to 225°C


-196°C / 300°C

MAX ΔP : 17,5 barg

AT - Direct operated temperature regulators

AM - Direct operated, spring pressure regulators

FUNCTION : Reducing / Relief



NP / DIN)




BODY MATERIAL : Carbon steel,

Stainless steel


(std)

DIAPHRAGMS : Polychloroprene



0,5 - 7 barg


-20°C / 235°C


CONTROL VALVE

ACP - Pneumatically operated control valves

FUNCTION : Control / On off



PN)





Stainless steel


(std)


MAX TEMPERATURE : 235°c

ELECTRIC ACTUATOR : 24 / 110 /

230V - 50 HZ

VRE - Electrically operated control valves

FUNCTION : Reducing /

Backpressure / On off



PN / DIN)





Stainless steel


(std)




-196°C / 540°C

MCP - Pneumatically operated control valves

FUNCTION : Reducing /

Backpressure / On off



PN)



CV : Da 4,7 a 561


Stainless steel




-196°C / 540°C


DESUPERHEATERS

DSH VARIFLOW - Variable area desuperheaters

FUNCTION : Temperature control of

the superheated steam

DIAMETERS : Water : 1” - 1 1/2” - 2”

- 3” / Steam : 3” - 4”

CONNECTIONS : Flanged (ANSI)



BODY MATERIAL : Cr-Mo alloy steel

TRIM MATERIAL : Hardened

Stainless steel

MAX TEMPERATURE : 570°C

(steam side)

NR. OF NOZZLES : 6 - 9

RANGEABILITY : Up to 50:1

MAX WATER FLOW : 50m3/h

ΔP : 60 barg (open position) - (80

barg (special drawing)

DSH VARIFIX- Fixed Nozzle desuperheaters



DIAMETERS : Water : 1” - 1 1/2” - 2”

- 3” / Steam : 3” - 4”

CONNECTIONS : Flanged (ANSI)




TRIM MATERIAL : Hardened

Stainless steel

MAX TEMPERATURE : 570°C

(steam side)




ΔP : 40 barg

DSH VARISPRING- Spring desuperheaters



DIAMETERS : Depending on

installation

CONNECTIONS : Depending on

installation


CV : From 1 up to 15


TRIM MATERIAL : Hardened Stainless

steel

MAX TEMPERATURE : 570°C (steam

side)




(maximum single nozzle size)

ΔP : 25barg

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