TYPE 1031 HEAVY-DUTY SCOTCH-YOKE ACTUATOR
There are several important considerations for evaluating actuator design and overall performance.
Among these considerations are torque output versus cost and size; effectiveness of seals, ease of mounting and adding accessories.
RSVP 1031 actuators are computer designed to properly balance these criteria and to provide the alternative or combination of alternatives that best fit your particular needs.
Quality, safety, dependability and efficiency are built into every RSVP 1031 actuator.
The body configuration is computer designed to optimize the transmission of force through the piston rod to the torque plug. Sturdy bearing surfaces assure effective sealing and long life through efficient torque transmission. A thrust pin is secured to the piston rod, and a roller is placed over the pin to allow free movement within the slot of the torque plug. This acts to reduce friction and wear. The torque plug has a closed cast slot; it is not open on one end. As a result, there will be no lost motion due to springing open under high torques. Obviously, to obtain maximum efficiency, all tolerances are closely held.
More than economy, efficiency means dependability. For example, the journals of the torque plug provide wide bearing surfaces for ease of rotation. These also resist side thrust and wear caused by possible misalignment in mounting to a valve or damper. The piston rod slides through bronze bearings secured between the body and the cylinder adapter or rod cover. The bearing is designed to minimize friction, but the area is sufficient to counter side thrust and wear.
The RSVP 1031 actuator is designed with three modules. The first module is the center-body. We offer five different sizes of center-bodies; 26, 33, 45, 60 and 80. The second module is the power assembly. The third is the spring assembly. The power and spring assembly modules are removable, serviceable and interchangeable without removing the center-body module from the valve. This procedure does not require any special tools.
1. Body Assembly: Heavy duty
modular type body allows every actuator to be made spring return or double
acting.
2. Scotch-Yoke: A balanced scotch-yoke mechanism provides optimum
torque output and maintenance simplicity by transforming the linear travel
of the piston into a 90 degree rotating movement.
3. Thrust Pin & Roller:
A thrust pin is secured to the piston rod and rollers are placed over
the pin to allow free movement within the slot of the torque plug.
4. Torque Plug Seal: O-rings are located both top and bottom preventing
environments from entering the body housing.
5. Yoke Bearings: Located on both top and bottom of the scotch-yoke,
these UHMW polyethylene replaceable bearings allow the actuator to cycle
more than any actuator in its class and aid in applications where the
actuators are left in one position for years.
6. Stop Bolts with Jam Nuts:
These bi-directional travel stops are an integral part of the actuator
allowing 80 degree to 100 degree total travel adjustment. Internal travel
stops are optional to prevent tampering.
7. Piston Rod: The piston rod is one continuous steel rod made
of 1045 steel bar with a hard chrome plating eliminating any side load
deflections. This design also allows our maximum operating pressure of
250 psig to apply to all our 1031 actuators.
8. Rod Bearings: These replaceable bronze SAE 660 bearings are
secured between the body and the cylinder adapter, or rod cover. The bearings
are designed to minimize friction.
9. Rod Seals: This dynamic seal between the rod bearings and piston
rod is a molythane
poly-pak seal. The o-rings load the molythane lips for better low pressure
sealing. As the pressure increases, the lip loading is increased, maintaining
an effective seal. There is also a GarlockTM gasket between the body and
the adapter.
10. Piston: Each piston on all 1031 actuators has the option of
having two piston seals on each piston. This allows longer life in high
cycle applications.
11. Cylinder: The cylinders are finely honed to a very low RMS
finish, and then coated with XYLANTM. This bonds to the chemically prepared
surface of the steel cylinder so effectively that unlike other coatings,
cracking and flaking are virtually eliminated. This fluoropolymer coating
is highly resistant to abrasion and thermal shock providing excellent
lubricity and low friction properties. Corrosive properties of salts and
other chemicals normally found in the atmosphere or instrument air supply
system will not adversely affect its performance. Stainless Steel and
AmalgonTM cylinders are also available.
12. Spring: Each spring is self-contained and pre-loaded in the
cylinder. This prevents any danger when the actuator is serviced and allows
for field exchange of springs.
RSVP ESD systems are suitable for use in high and low pressure shut-down applications utilizing either a pneumatic or hydraulic media.
The Control Systems are widely used as Emergency Shut-Down (ESD) or Surface Safety Valve (SSV) systems.
They are designed for the remote shut-down of a Pipeline, Flow-Line or Wellhead that achieves a high or low pressure condition.
Limit switches: For remote position indication & sequencing.
• Electric or pneumatic
• Watertight or explosion proof
• SP-DT or DP-DT
• Low power
• AS-Interface and Device Net
Pressure switches: A device which transmits an electrical signal at a preset pressure.
Positioners: Utilize plant air as the power source to precisely position an actuator relative to a control signal (such as 3 to 15 psig instrument air) from a remote device.
Transducers: Convert an electrical control to a pneumatic control signal (e.g., 4 to 20 ma 3 to 15 psig).
Filters and lubricators: Filters are recommended when the condition of plant or instrument air could affect the performance of control devices. Lubricators are recommended in all systems not operated by positioners.
Solenoid valves: For remote electrical actuation:
• General purpose or explosion
proof
• Voltage (AC or DC)
• 2-way
• 3-way (1 for spring return actuator)
• 4-way (1 for double acting actuator)
• Maximum pressure and temperature
Pneumatic pilot valves: For remote pneumatic actuation.
Check valves and shuttle valves: To allow flow in only one direction or to divert flow to another direction.
Quick exhaust valves: To permit fast opening and/or closing by exhausting the cylinder directly to atmosphere.
Speed control valves: To throttle the air flow to and from the actuator to meet the operational characteristics of the system.
Regulators and relief valves: To regulate the supply pressure to the actuator
Jackscrew: A jackscrew override
is threaded in the cylinder end and directly pushes the
piston in the other direction. It is recommended only as an economical
emergency override for smaller actuators. Two jackscrews are required
for double acting models, and one for spring return models.
Manual gear overrides: Gear overrides are available on most units.
Hydraulic override systems: These are hydraulic pump systems with built-in relief valves for safety, and manually operated valves to disengage the normal system. A hand lever type pump is used on all models. The mounting attitude of the actuator should be specified when ordering for proper orientation of the accessories.
Air pumps and automatic accumulator
systems are available on all units.
Partial stroke devices, mechanical and electrical, are available on
all units.
To download, view and print the Type 1031 Instruction Manual, just click on the image below. This a 60-second download.
Dimensional data: Torque outputs and other technical information, please refer to RSVP’s Technical Brochure. To download, view and print this Technical Brochure, just click on the image below.
RSVP 1031 model numbers are easy to understand.
For example, MODEL NO. 26051SR080C1000C
26
Indicates the size of the body and torque plug
05 Indicates
pressure cylinder diameter
1 Indicates
the number of pressure cylinders
SR Indicates a
spring return model
080 Indicates spring
rating
C Indicates
failure mode
1 Indicates
internal soft seal’s material
0 Indicates
override type
00 Indicates
special requirements
C Indicates
cylinder material
