Standard Regulator

Spring Guide                                                       

PROBLEM:

High control pressure requires lots of spring force. Accurate control needs sensitive springs. These combined results in long control springs which buckles near the min working length. This lateral deflection can wear the inner wall of the spring case, wear the spring itself, as well as contribute to misalignment of parts, causing premature wear and reduced performance.

SOLUTION:

The MR105/108 utilizes a simple design where the adjusting screw fits into the upper spring seat and fixes the end, preventing it from tilting. The upper spring seat then extends into the spring and acts a guide to restrain the control spring.

CUSTOMER ADVANTAGE:

This prevents premature wearing of parts and allows optimal performance at all operating conditions to stabilize unit at max
flow.

Rugged Design Spring Case CF8M Option                                                       

PROBLEM:

Control valve actuators designed for operation with control air used as direct operated regulator where actuator exposed to harsh environment and process fluid.

SOLUTION:

Robust actuator design where P1 can equal P2 without damage (HP only). Complete actuator available in WCC steel, CF8M SST, or CF3M SST (not just one casing). NCF coated Grade B7 alloy steel bolting used on body to body flange connection for steel constructions and B8M CLII on SST constructions.

CUSTOMER ADVANTAGE:
Regulator design with suitable materials of constructions to withstand the harshest application requirements.

Two Piece Spring Case                                                       

PROBLEM:

In order to meet respond to emergency issues many customer must stock parts on their shelf. Complex design not only reduce number of shared parts, but the construction more difficult to modify or adjust.

CUSTOMER ADVANTAGE:
Stock fewer parts and still have all parts needed to modify unit without having to break critical seals and worry about proper
assembly.

SOLUTION:

Design utilizes two piece spring case so spring barrel may be removed and spring changes without ever compromising the critical diaphragm seal. This allows customer to stock 1-2 units with multiple spring to service all constructions. Also, adjustment of newly assembled unit is simple turn of an adjusting screw.

Reduced Actuator Spring Combination                                                   

PROBLEM:

Control valve body and actuator is adapted to perform as direct-operated regulator. Result is large number of spring and actuator combinations to cover standard operating range. The Fisher 655/ED utilizes 49 different combinations of springs &
actuators to cover 1-174 psig control pressure range.

SOLUTION:

MR105/108 designed using just 2 actuators and 6 springs to cover set points from 5 psig all the way to 300 psig for both pressure reducing and back pressure units.

CUSTOMER ADVANTAGE:
Customer is able to meet all their demanding pressure control applications without switching to high pressure units or trying to determine necessary configuration out of 49 combinations of springs/actuators.

Cage Guided Plug - Low Flow Control / Stability Fast Response

PROBLEM:

The regulator fails to immediately respond to sudden changes in the control pressure. This causes spikes or drops in control
pressure and can result in unintended trip of pressure monitoring equipment or worse, damage to sensitive (and expensive!) equipment.

SOLUTION:

The MR105/108 utilize a direct-operated regulator design were the control pressure acts directly on the main diaphragm for immediate valve position response to control pressure changes. The design also uses a quick-open cage for maximum flow at minimum travel while minimizing stem friction to further speed of response.

CUSTOMER ADVANTAGE:

Best in class flow performance and speed response result in tighter pressure control to prevent damage to sensitive and expensive equipment as well as reducing unintended trips in the system.

PROBLEM:

Regulators design for max flow conditions operate close to the seat during normal and min flow conditions resulting in unstable control and cycling that reduces service life.

SOLUTION:

Cage guided plug positioned firmly by both opening and closing springs results in extremely stable operation even close to the seat.

CUSTOMER ADVANTAGE:

Better control and longer service life at all flow conditions.

Large Flow Areas Best in Class Capacity                                                       

PROBLEM:

Lack of regulator capacity requires larger and more expensive regulator & piping selection. Larger flow demand will also require the control pressure to deviate further from set point resulting in poor pressure control.
money

SOLUTION:

Large flow area combined with sensitive springs, large diaphragm area, and quick-open cage result in best in class flow performance

Customer Advantage:

Smaller regulators & piping can be utilized saving space and money.

Class VI Shutoff Option                                                       

PROBLEM:

Small leakage through regulator, even at zero travel. Class IV shut-off can still leak 0.1% of rated capacity. If the regulator is still passing flow when it is “shut-off” then in can not be used in dead-end service or applications where there will be zero flow demand for any extended amount of time.

CUSTOMER ADVANTAGE:
Regulator with Class VI shut-off can be used in dead-end service without pressure build-up or safety relief valve actuating.

SOLUTION:

Time proven EGR valve trim achieves bubble tight Class VI shut-off with soft dual seat design.

Bump Connection                                                       

PROBLEM:

High control pressures require large springs with very high spring rates. In the absence of control pressure, the full force of these springs is then pushing down on the stem/valve plug and damaging seals in spring to close designs (BPV).

SOLUTION:

Developed a design with bump connection where stem travels through the plug. A closing spring is then used to supply adequate closing force.

CUSTOMER ADVANTAGE:

The design offers the best of both worlds. A stiffer control spring may be used for demanding operating conditions without risking damage to seals or compromising Class VI shut-off performance.