Specifications: SAI125AX413CAT — SAI series double-acting single-rod cylinder; 125 mm bore × 413 mm stroke; SUS420J2 rod (A); non-magnetic piston; single rear clevis (CA); TPU seals; NPT1/2 ports (T).
Product Catalog
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For detailed product dimensions and mounting drawings, please download and refer to the PDF catalog.
SI to SAI replacement guide
Model Code Explained
| Code |
Meaning |
| SAI |
Standard double-acting single-rod cylinder |
| 125 |
125 mm bore |
| A |
SUS420J2 stainless steel |
| X |
Separator before stroke |
| 413 |
413 mm stroke |
| No magnet suffix |
Without built-in magnet |
| CA |
Single rear clevis |
| No seal suffix |
TPU seal option |
| T |
NPT1/2 working ports |
Technical Specifications
| Parameter |
Value |
| Model |
SAI125AX413CAT |
| Action |
Double acting, single rod |
| Bore |
125 mm |
| Stroke |
413 mm; Special stroke; confirm order and delivery conditions |
| Piston rod material |
SUS420J2 stainless steel |
| Magnetic piston |
Without magnet |
| Mounting selection |
Single rear clevis |
| Seal option |
TPU |
| Working ports |
NPT1/2; two working air ports |
| Working medium |
Air filtered to 40 µm or finer |
| Operating pressure |
0.15–1 MPa (1.5–10 bar; approximately 22–145 psi) |
| Proof pressure |
1.5 MPa (15 bar); not continuous operating pressure |
| Temperature |
-20 to 70 °C; apply the complete system limits |
| Piston speed |
30–500 mm/s |
| Stroke tolerance |
+1.5 / -0 mm |
| Cushioning |
Adjustable pneumatic cushion; 40 mm nominal cushion reference |
| Rod diameter / end thread |
32 mm / M27×2.0 |
| Cylinder reference weight |
11661.75 g; catalog calculation, not measured shipping weight |
Reference weight = 5611.3 + 14.65 × 413 g, decimal grams, from the matching non-magnetic SAI single-rod base. A/B rod and H/N seal mass differences are unquantified: not certified variant mass. Excludes brackets, rod joints, sensors and packaging; actual weight prevails.
The 40 mm nominal cushion distance does not guarantee usable deceleration length for shorter strokes. Verify actual load/speed performance.
Features and Operation
ISO15552 standard cylinder, formerly ISO6431.
Compact special-shaped bidirectional piston sealing structure with oil storage.
Corrosion-resistant profiled aluminium tube; no tie rods; external sensor grooves.
Stable adjustable pneumatic cushioning.
Multiple cylinder variants and mounting accessories available.
External and Mounting Dimensions
A+stroke ends at rear-cover face; overall formulas add rear boss NA once. Bare body excludes accessories, sensors, joints and packaging. Magnetic/nonmagnetic dimensions match. Drawing-specific symbols are not extra overall dimensions. Numbers are mm; threads are explicit. For detailed product dimensions and mounting drawings, please download and refer to the PDF catalog.
| Basic dimension / drawing symbol |
Dimension (mm) / thread |
| Illustrated A + stroke to rear-cover face |
692 mm = 279 + 413 |
| Body face span: AC + stroke |
573 mm = 160 + 413 |
| Derived bare retracted length: A + stroke + NA |
696 mm = 279 + 413 + 4 |
| Derived bare extended length: A + 2 × stroke + NA |
1109 mm = 279 + 2 × 413 + 4 |
| Body cross-section |
140 × 140 mm |
| Base drawing symbols |
A=279 mm before adding the actual stroke;AB=119;AC=160 mm before adding the actual stroke;AD=46;AE=46;B=140;D=32;DA=74;E=M27×2.0;EA=54;F=41;FA=13.5;M=60;MA=45;H=27;K=M12;KA=22;KB=110;N=60;NA=4;P=NPT1/2;PA=23;PB=14 |
Selected Mounting Dimensions
| Accessory / drawing symbols |
Dimension (mm) / thread |
| CA — Single rear clevis; F-SE125CA |
A + stroke=692 = 279 + 413;C + stroke=573 = 160 + 413;S=134;T=110;DC=50;DD=24;DE=25;DJ=33;DQ=69.7 |
Mounting and Rod-End Accessories
| Mounting option |
Part code and material |
| LB — Axial foot mounting |
F-SI125LB; Ductile cast iron |
| FA — Front flange mounting |
F-SI125FA; Ductile cast iron |
| CA — Single rear clevis |
F-SE125CA; Ductile cast iron |
| CB — Double rear clevis |
F-SE125CB; Ductile cast iron |
| CR — Single clevis connection |
F-SI125CR; Ductile cast iron |
| TC — Intermediate trunnion mounting |
F-SAI125TC; Ductile cast iron |
| FTC — Front-cover trunnion mounting |
F-SI125FTC; Ductile cast iron |
| TCM1 — Trunnion support type 1 |
F-SI125TCM1; Ductile cast iron |
| TCM2 — Trunnion support type 2 |
F-SI125TCM2; Aluminium alloy |
| FB — Rear flange mounting |
F-SI125FA; Ductile cast iron |
FA/FB share a flange plate at different positions. CR requires CB. TC/FTC need the listed TCM1/TCM2: support size numbers may differ from bore. Confirm package and fasteners.
TC is adjustable and separately orderable for this bore. Drawing-reference support centers: position for actual load.
TC locking torque: 10–12 N·m; static holding-force reference: 12000 N, not cylinder thrust or payload. Above this, specify factory nonstandard fixed TC. Place bracket on barrel ledges and position it. Pre-tighten; check bracket and barrel sloping faces contact. 50–125: tighten 8 black screws through pre-, intermediate and final tightening, then tighten 8 white screws.
Drawing holes: LB 4 AP; FA/FB 4 BP; CR 4 K through-holes and 4 L counterbores; TCM1 4 E; TCM2 4 L through-holes and 4 K counterbores. CA DQ/CB CP tolerance: ±0.1 mm. Hole counts do not specify supplied fastener quantities.
Rod-End Joint Dimensions
| Joint / drawing symbol |
Dimension (mm) / thread / angle |
| I joint — F-M27X200I |
NC=30;ND=110;NE=139;NF=51;NG=45;NH=M27×2;NM=30;Reference weight=1201 g |
| Y clevis joint — F-M27X200Y |
NA=54;NC=30;ND=110;NP=55;NQ=139;NM=30;NH=M27×2;PA=64.2;PB=54.8;Reference weight=1473 g |
| Floating joint — F-M27X200F |
MA=136.5;MB=40;MC=14.5;MD=52.5;ME=59.5;MF=40;MG=13.5;MH=27;MI_MJ=M27×2;MK=5°;Reference weight=1470 g |
| Spherical rod-end joint — F-M27X200U |
PA=25;PB=70;PC=30;PD=51;PE=110;PF=145;PG=M27×2;PH=15°;PI=50;PJ=41;PK=37;Reference weight=1210 g |
M27×2.0 rod joints use the carbon-steel catalog category; subparts/finishes are unspecified. Select joints/guides for load. Joint mass is excluded from cylinder weight. Y drawing: no separate pin-kit code or guaranteed kit count.
Force and Application
| Parameter |
Value |
| Extension effective area |
12272 mm²; catalog rounded single-rod area |
| Extension at 0.5 MPa |
6136 N theoretical |
| Retraction effective area |
11468 mm²; catalog rounded single-rod area |
| Retraction at 0.5 MPa |
5734 N theoretical |
Theoretical axial force = effective area (mm²) × pressure (MPa), before friction/losses. Rod area reduces retraction area. Not safe working loads or guaranteed payloads.
Installation and Maintenance
Qualified personnel only. Before maintenance: secure loads, guard motion, isolate power/air and release residual pressure. Prevent unexpected restart motion; design for power/air loss.
Use clean, dry air filtered ≤40 µm; remove water, degraded oil and debris. Protect from dust, corrosion, coolant, weld spatter, vibration, heat and freezing; assess unusually dry air. Strong magnetic fields affect sensing.
Start unloaded; increase load gradually. Align rod/load; guide against side load, bending, impact and torque. Check long-stroke buckling, sag, support and air use. Rod joints do not replace guides.
Load-ratio guidance: ≤0.7 static/low speed; ≤0.5 at 50–500 mm/s; ≤0.3 above 500 mm/s. Not structural safety factors or payload guarantees; obey cylinder pressure/speed limits.
Fit flow controls at both ports; double action normally uses meter-out. Start closed; open gradually. Set cushions for load/speed without forcing screws. Heavy/fast loads may need an external absorber or deceleration circuit.
Compressibility/leakage defeat assumed precise prolonged closed-center stops or automatic multi-cylinder synchronization. Swing links need CA/CB/TC pivots, not rigid LB mounts forced through arcs. Match flange direction/support height to load.
Normally no added oil is needed. Once introduced, continuously use additive-free ISO-VG32 turbine oil. Oil-mist guide: ≤25 mg/m³; 0.5–5 drops per 1000 L. Size lubricator for flow; avoid excess/incompatible oil.
Clean pipes; keep sealant off leading threads. Start required tape 1.5–2 threads back. Verify tube pressure/temperature, OD/ID and bend radius. Hot spatter may require metal/flame-resistant tubing.
Protect sliding surfaces; periodically operate stored cylinders and prevent corrosion. Use the lowest cylinder/fitting/valve/tube/sensor/cable limit; temperature options do not raise other ratings.
Internal Components — SAI Catalog Reference
| Item |
Material reference |
| 1. Nut |
Carbon steel / stainless steel |
| 2. Piston rod |
S45C hard-chrome-plated ground bar / stainless steel |
| 3. Front-cover O-ring |
TPU |
| 4. Front cover |
Aluminium alloy |
| 5. Bushing |
Wear-resistant material |
| 6. Cushion O-ring |
TPU |
| 7. Barrel |
Aluminium alloy |
| 8. Piston-rod O-ring |
NBR |
| 9. Piston |
Aluminium alloy |
| 10. Piston O-ring |
NBR |
| 11. Wear ring |
Wear-resistant material |
| 12. Magnet |
Not fitted in this non-magnetic cylinder. Catalog magnetic-version reference: Plastic type for bores100 and below; rubber type for other bores |
| 13. Hexagon socket bolt |
Carbon steel |
| 14. Cushion seal |
TPU |
| 15. Rear cover |
Aluminium alloy |
| 16. Support screw cap |
Carbon steel / stainless steel |
SAI structure reference, not an option material certificate. Ordered rod/seal choices prevail: A/B is not an all-stainless cylinder; a seal option does not replace every elastomer.
Series Ordering Options
| Parameter |
Value |
| Rod material choices |
Blank: Medium-carbon steel; A: SUS420J2 stainless steel; B: SUS304 stainless steel |
| Seal choices |
Blank: TPU; H: Fluororubber; N: NBR |
| Magnet choice |
Blank: no magnet; S: magnet fitted, sensors separately selected |
| Thread choices |
PT, G or NPT as specified by the actual order; do not mix thread standards |
| Catalog standard strokes |
25, 50, 75, 80, 100, 125, 150, 160, 175, 200, 250, 300, 350, 400, 450, 500, 600, 700, 800, 900, 1000 mm |
| Maximum / allowable stroke |
1500 / 1800 mm; separate catalog limits, not a list of all standard strokes |
| Stroke tolerance bands |
0–250 mm: +1 / -0 mm; 251–1000 mm: +1.5 / -0 mm; 1001–1500 mm: +2 / -0 mm; above 1500 mm not specified |
Series alternatives are not simultaneous features. Confirm special strokes/unlisted combinations. Retain the full model; separately select mounts, joints, sensors and circuit parts.
Magnetic Sensing
This model has no built-in magnet. DMSE and CMSE magnetic sensors are not applicable to this piston as ordered; adding a sensor does not add a magnet. A separately confirmed magnetic cylinder configuration is required for magnetic detection.
Connection and Tube-Side Options
| Separately selected component |
Complete ordering codes; tube dimensions as labelled |
| NPC straight |
3/8 in OD: NPC3/8-1/2; 1/2 in OD: NPC1/2-1/2 |
| NPL elbow |
3/8 in OD: NPL3/8-1/2; 1/2 in OD: NPL1/2-1/2 |
| NPLL extended elbow — discontinued reference |
3/8 in OD: NPLL3/8-1/2; 1/2 in OD: NPLL1/2-1/2 |
| NPEB branch tee |
3/8 in OD: NPEB3/8-1/2; 1/2 in OD: NPEB1/2-1/2 |
| NPED run tee |
3/8 in OD: NPED3/8-1/2; 1/2 in OD: NPED1/2-1/2 |
| NPYB Y fitting |
3/8 in OD: NPYB3/8-1/2; 1/2 in OD: NPYB1/2-1/2 |
| NPH banjo elbow — discontinued reference |
3/8 in OD: NPH3/8-1/2; 1/2 in OD: NPH1/2-1/2 |
| NPHF female-branch banjo — discontinued reference |
3/8 in OD: NPHF3/8-1/2; 1/2 in OD: NPHF1/2-1/2 |
| NPHW twin banjo — discontinued reference |
3/8 in OD: NPHW3/8-1/2; 1/2 in OD: NPHW1/2-1/2 |
| NPZB cross fitting — discontinued reference |
3/8 in OD: NPZB3/8-1/2; 1/2 in OD: NPZB1/2-1/2 |
| NBPC metal straight — discontinued reference |
3/8 in OD: NBPC3/8-1/2; 1/2 in OD: NBPC1/2-1/2 |
| NBKC compression fitting — discontinued reference |
3/8 × 1/4 in OD × ID: NBKC3/8-1/4-1/2; 1/2 × 1/3 in OD × ID: NBKC1/2-1/3-1/2 |
| NBB male–male adapter — discontinued reference |
male NPT1/4 ↔ male NPT1/2: NBB1/4-1/2; male NPT3/8 ↔ male NPT1/2: NBB3/8-1/2; male NPT1/2 ↔ male NPT1/2: NBB1/2-1/2 |
| NBD male–female adapter — discontinued reference |
female NPT1/8 ↔ male NPT1/2: NBD1/8-1/2; female NPT1/4 ↔ male NPT1/2: NBD1/4-1/2; female NPT3/8 ↔ male NPT1/2: NBD3/8-1/2 |
| NBZ unused auxiliary plug |
NBZ1/2 |
| NBSL valve-exhaust silencer |
NBSL1/2 |
| NBSLM miniature valve-exhaust silencer |
NBSLM1/2 |
| NBESL adjustable valve-exhaust silencer — discontinued reference |
NBESL1/2 |
| NPTL push-lock flow control |
5/16 in OD: NPTL5/16-1/2A,NPTL5/16-1/2B; 3/8 in OD: NPTL3/8-1/2A,NPTL3/8-1/2B; 1/2 in OD: NPTL1/2-1/2A,NPTL1/2-1/2B |
| NPSS universal flow control — discontinued reference |
1/2 in OD: NPSS1/2-1/2A,NPSS1/2-1/2B |
| NPSA tube-to-tube flow control |
5/16 in OD: NPSA5/16; 3/8 in OD: NPSA3/8; 1/2 in OD: NPSA1/2 |
| ASC separate inline flow control |
two female NPT1/2: ASC30015T |
| GAFR upstream filter/regulator |
female NPT1/2: GAFR30015ST,GAFR40015ST |
Separate options; not an included kit or stock promise. Connect both SAI125 working ports with NPT1/2 fittings/correct seals; check insertion depth, tool/rotation clearance, flow and tube loads. PT/G/NPT are not interchangeable. The M27×2.0 rod thread is not an air port.
Discontinued families are historical references; confirm remaining availability or approved replacements before ordering.
Use suitable soft nylon/PU; match exact OD and compression-fitting ID. Inch tube sizes are exact: 1/4 = 6.35, 5/16 = 7.9375, 3/8 = 9.525 and 1/2 = 12.7 mm; do not substitute nominal metric sizes. NPHF has male RA/extra female RB of NPT1/2; connect or permissibly seal RB, not a tube socket. Tees/Y/cross/distributors must not bridge chambers or unrelated controls.
Standard push-in fittings, direct/threadless controls and listed silencers: 0–1 MPa, −20–70 °C. NBPC: 0–1 MPa, 0–150 °C; SAI pressure path 0.15–1 MPa. NBKC/NBB/NBD/NBZ: 0–1 MPa, 0–150 °C; SAI pressure path 0.15–1 MPa. General cylinder −20–70 °C with 0–150 °C parts gives 0–70 °C or narrower. Apply lower valve/tube/sensor limits; component vacuum data do not rate a vacuum cylinder. NBPC does not share the metric BPC 0.9 MPa limit.
Install threads using the body hex, not locking nut; fully insert tube before tightening. The printed 1/3 in compression ID is literal; do not round it to a metric tube. NBB/NBD are same-standard adapters: BB male–male, BD male–female; table labels the other end. Match gender/size/flow; no cross-thread conversion. NBZ closes permitted unused auxiliary ports only, never active cylinder ports.
Cylinder-end A controls thread→tube exhaust (meter-out), with free reverse supply; B controls tube→cylinder supply (meter-in). A is usual for double action; B needs a designed meter-in circuit. Start closed/open slowly. Closed leakage is allowed: not safety shutoffs. NPTL caps on 1/2-port variants: limit: 0.32 N·m, not pipe-thread torque. Do not force caps/end stops. NPSA is an inch tube-to-tube control without A/B suffixes; match both ODs/check-throttle symbol.
Listed silencers serve separate valve exhaust: match thread/flow/backpressure. Not cylinder-port fittings, inlet filters or shutoffs. NBESL adjustment changes backpressure.
ASC30015T: separate two-female-NPT1/2-port inline control; needs male fittings. Follow P/A/check-throttle symbol. 0.05–0.95 MPa, −20–70 °C and 40 µm-or-finer filtered air; SAI pressure path 0.15–0.95 MPa before lower limits. Rated flow is not guaranteed cylinder speed.
GAFR30015ST,GAFR40015ST: separate upstream NPT1/2 filter/regulator: 40 µm, PC bowl, differential/manual drain, bracket/round gauge, no reverse-flow valve. Inlet ≤1 MPa, setting 0.15–0.9 MPa, −5–70 °C non-freezing. Respect IN/OUT, flow/pressure loss, condensate, bowl environment and downstream limits. Not cylinder-mounted or a vacuum regulator.
Match separate inch tubing and both endpoints. Metric coils, PSA/GPSA and PPA are not specified for inch sockets. Match coil length and tube pressure/temperature to the circuit.
A 16 × 11 mm reference tube needs separately specified 16 mm endpoint fittings and controls; the listed inch sockets do not form that connection.
Separate Valve, Tube and Sizing Selection
No bore-specific valve/tube or speed-flow example is established here for this bore. Select separately from actual flow, pressure, temperature, thread, tube OD/ID, load and exhaust conditions; a smaller-bore example is not a validated substitute.
Use the catalog above for dimensions, mounting drawings and symbol positions. Before installation, check full configuration, space and separately selected accessories.