Single Acting/Double Acting/Single Reserve Acting/Pneumatic Actuators Series X400: Top Cylinder

• Brand: Snt
• Power: Pneumatic
• Adjusted Form: Regulated Type
• Working Type: Straight Trip
• Pressure: Medium Pressure
• Work Temperature: Normal Temperature
• Model NO.: 1-X400 SERIES CYLINDER PNEUMATIC ACTUATORS
• Acting Type: Spring Return
• Material: Aluminum
• Customized: Customized
• Structure: Piston Type
• Size: P200(S)/P250(S)/P300(S)/P400(S)/P500(S)
• Cylinder Inside Materials: Chromium-Plated and Polished
• Actuator Body Two Heads: Aluminium/ Steel Cast
• Actings: Direct Acting/Reverse Acting
• Rated Travel: 17/25/34/45/60/76/100/120/150/200mm
• Air Pressure: 0.3/0.36/0.45MPa
• spring Range: 0.10~0.20MPa/0.12~024MPa/0.15~0.30MPa
• Standard Design Pressure: 10.5 Bar
• Air Test Pressure: 1, 5 Max Working Pressure
• Standard Minimum Temperature: -20 Degree
• Standard Maximum Temperatur: +80 Degree
• Standard Certifications: ISO 9001:2008
• Actuation Model: Single Acting / Double Acting
• Handwheel: Top-Mounted/Side-Mounted
• Diaphragm Diameter (mm): 200/250/300/400/500
• Transport Package: Wooden
• Trademark: SNT
• Origin: China
• HS Code: 8481804090
• Production Capacity: 500000PCS/Year

Product Description

 

Product Description

<sup>The 1-X400 series linear stroke piston-type pneumatic actuators utilize cold-drawn hydraulic pipes as cylinder bodies. Through honing and extrusion processes, the wear of dynamic sealing elements is significantly reduced, enhancing the durability of the actuator. Compared to membrane-type linear stroke actuators of the same specifications, they offer greater thrust. With a simple structure, lightweight design, and compact size, they represent a high-performance pneumatic linear stroke actuator.

The 1-X400 series linear stroke piston-type pneumatic actuators are available in both double-acting and single-acting configurations. When combined with linear stroke valves, they can be used for regulation or on-off control. Equipped with accessories such as pneumatic control valves, quick exhaust valves, and pneumatic actuators, they can achieve rapid cutoffs, with cutoff times of 1S, 2S, 3S and 4S and other levels.</sup>

 

Pneumatic cylinder actuators are well suited to those applications beyond the usual field of the pneumatic diaphragm type actuators: they can be feed with high air pressure to give high thrusts; they have about no limit in stroke, their thrust/travel characteristic is quite linear, their performance shall not be reduced for low temperature service and their ratio between overall dimensions (or weight) and thrust is very interesting.

ln spite of such advantages,cylinders require accurate manufacturing and careful finishing which can bring up costs,together with the need for a positioner because of the high dead-band of piston not suited to a good throttling operation.

Cylinder actuators 1-X400 series can be fitted on all types of globe and angle valves manufactured by SNT.

 

 

 

<sup>Single-action (S.A.) actuators consist of a spring-opposed piston actuated by air pressure. They offer the advantages of a simple fail-safe action (when air pressure fails, the compressed spring load overcomes the pressure load and moves the stem to open or to close the valve port according to required fail-safe action),and of a good stability when the load on the plug varies.

On the other hand in comparison with double-action (D.A.) actuators, they show lower net thrusts and overall dimensions growing more and more with the increase of supplied air pressure and required stroke.

Double-action actuators with return spring may offer a good compromise: the full thrust of the air pressure on one side of the piston,is balanced partly by a compressed spring and partly by the air pressure on the other side of the piston. So to get a fail-safe action,there will be no need for complicate and little reliable pneumatic apparatus and, moreover,the net thrust of air pressure is only partly reduced by the spring thrust.</sup>

 

Design Details

8 bar represent both the rated supply pressure of cylinder and the limit for tightness of sliding seals of piston. However all actuators are hydrostatically tested at 10.5 bar before delivery. Temperature limits for continuous service at 8 bar are given in the table of materials.

Actuator Body
<sup>Cylinder is worked from a precision steel tube. Inside surface is lapped, chromium-plated and polished.
The two heads are aluminium or steel cast and are available in some different shapes to meet the requirements for assembly on valves or for operation
1. With a fork on the upper or lower head for pivoting assemblies (e.g. to actuate butterfly valves.
2. With a flange for stiff assembling on valve yokes (e.g. to actuate globe or angle valves).</sup>

Piston
Piston is high-strength steel and is fitted with one (S.A.) or two (D.A.) rubber sealing rings and two (S.A.) or one (D.A.) loaded-teflon guiding skid.

Stem
Stem is machined from a stainless steel rod, ground, rolled and threaded at the end which remains outside the cylinder. Actuator stem is connected to valve stem by a two-piece, bored and threaded block, clamping the screwed ends of the two stems.
Stem is guided by a double bronze bushing fitted in the lower head which also holds a felt ring to wipe the stem and a sealing ring (except for S.A. direct-acting actuators) to pre-vent leakage.

^{Quality Assurance and Certification}

^{Design, manufacture and test procedures of linear pneumatic actuators are complying to the highest quality and efficiency standards and are based on SNT following awarded standard certifications:}

• ^{ISO 9001:2008}
• ^{ISO 14001-2004 Environmental Management System}
• ^{OHSAS 18001:2007 Occupational Health and Safety Assessment Series}

^{SNT linear pneumatic single acting and double acting actuators are also designed and certified according to:}

• ^{European Pressure Equipment Directive 97/23/CE ( PED )}  
• ^{IEC 61508:2000 for application up to SIL 3 level (refer to page 3 picture)}

 

Technical Standard Preformance
Pressure Range

• ^{air working pressure range: 2 ÷ 10 bar}
• ^{standard design pressure: 10.5 bar}
• ^{air test pressure: 1,5 max working pressure}
• ^{Higher working pressure range or design pressure available on request.}

Environmental Temperature Range

• ^{standard minimum temperature : -20ºC}
• ^{Standard maximum temperature: +80ºC}
• ^{Available execution for following environmental conditions (refer to actuator code legend options ):
  Minimum temperature -60ºC
  Maximum temperature +150ºC 
  For different temperature contact our sales}

^{Medium Supply}

• instrument air (dry no-lubricated)
• sweet natural gas (dry no-lubricated)
• nitrogen
• execution for low pressure oil available on request
• different medium supply on request

Customise execution on request

^{SNT production is highly oriented in designing special execution to satisfy a wide range of customised requirement such as :}

• ^{On-off or modulating execution}
• ^{Execution for offshore or highly aggressive environmental}
• ^{Design of customised coupling yokes to fit any kind of valve topwork}
• ^{Execution with mechanical end stop screws in opening or closing or both directions}
• ^{Fast acting execution for HIPPS or Emergency Shutdown application}
• ^{Execution with dampers or special integral quick exhaust valve}
• ^{Subsea design}

Please contact our sales department for technical evaluation in case of different customised requirement.

Controls

^{1-X400 actuators can be supplied fully equipped with control component packages to full fill customer requirement and comply to technical specifications for the various industrial control applications for on/off, modulating or ESD service
Controls are designed based on SNT technical skill and long experience in valve automation.}

Double Acting
 

1	BOLT	11	CYLINDER	21	STROKE PLATE
2	ACTUATOR YOKE	12	BOLT	22	STROKE INDICATOR
3	STEM CONNECTOR	13	UPPER CYLINDER COVER	23	SCREW
4	ANTI-ROTATION PLATE	14	WASHER	24	FLANGE
5	SCREW	15	NUT	25	SEAL RING
6	ACTUATOR STEM	16	LIFTING BOLT	26	O-RING
7	BOLT	17	WASHER	27	GUIDING BUSHING
8	LOWER CYLINDER COVER	18	NUT	28	O-RING
9	O-RING	19	O-RING	29	O-RING
10	PISTON	20	GUIDING	30	SCREW

Single Acting

1	BOLT	21	NUT	41	SCREW
2	ACTUATOR YOKE	22	O-RING	42	STROKE INDICATOR
3	STEM CONNECTOR	23	SCREW	43	O-RING
4	ANTI-ROTATION PLATE	24	YOKE	44	WASHER
5	SCREW	25	O-RING	45	WASHER
6	ACTUATOR STEM	26	LEAD SCREW	46	LOCKNUT
7	BOLT	27	BOLT	47	BEARING
8	LOWER CYLINDER COVER	28	BEVEL GEARBOX	48	PIN
9	SCREW	29	O-RING	49	BEARING STEM
10	SPRING GUIDING	30	GUIDING	50	PIN
11	NUT	31	O-RING	51	O-RING
12	SPECIAL NUT	32	SPRING SEAT	52	SEAL RING
13	WASHER	33	BEARING	53	FLANGE
14	BOLT	34	PIVOT	54	O-RING
15	CYLINDER	35	BEARING	55	O-RING
16	SPRING	36	BOLT	56	GUIDING BUSHING
17	PISTON	37	WASHER	57	SCREW
18	UPPER CYLINDER COVER	38	NUT	58	ANTI-ROTATION PLATE
19	WASHER	39	AIR VENT	59	PIN
20	NUT	40	STROKE PLATE

Single Acting(Reverse-Air to Open)
 

1	BOLT	16	WASHER	31	SCREW
2	ACTUATOR YOKE	17	UPPER CYLINDER COVER	32	O-RING
3	STEM CONNECTOR	18	SCREW	33	O-RING
4	ANTI-ROTATION PLATE	19	SPRING GUIDING	34	GUIDING BUSHING
5	SCREW	20	LIMIT ROD	35	PLUG
6	ACTUATOR STEM	21	LIFTING BOLT	36	PLUG
7	BOLT	22	AIR VENT	37	PIN
8	WASHER	23	O-RING	38	SEAL RING
9	LOWER CYLINDER COVER	24	O-RING
10	CYLINDER	25	O-RING
11	PISTON	26	GUIDING
12	NUT	27	STROKE PLATE
13	SPRING	28	STROKE INDICATOR
14	BOLT	29	SCREW
15	NUT	30	FLANGE

 

Production application

 

 

 

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