ISO 9001:2015 Certified

'SHAPING INDUSTRIES WITH THE FINEST STEEL'

SAE MS Male Adapter Manufacturer

TES-LOK SAE MS Male Adapters — compression tube fittings with SAE/MS straight UNF thread and O-ring boss (ORB) seal for leak-free connection of instrument tubing to SAE-ported hydraulic valves, pumps, cylinders, manifolds, and aerospace assemblies. ISO 9001:2015 certified. SAE J514 • SAE J1926 • MS16142. Made in India.

SS 304 / SS 316 Brass Carbon Steel SAE UNF Straight Thread O-Ring Boss Seal Dash -4 to -32 SAE J514 / MS16142 ISO 9001:2015
SAE MS Male Adapter SS 316

TES-LOK SAE MS Male Adapter

SAE MS Straight Thread Male Adapter

SAE MS Straight Thread Series

O-Ring Face Seal Fitting

O-Ring Face Seal (ORFS) — Related

What Is an SAE MS Male Adapter?


Definition: An SAE MS Male Adapter is a compression tube fitting whose process-connection end is a SAE / MS straight UNF (Unified National Fine) thread with a machined O-ring groove behind the threads. This O-ring boss (ORB) configuration — standardised under SAE J1926 / ISO 11926 and the military standard MS16142 — seals by compressing an O-ring between the fitting shoulder and a flat or chamfered boss face in the female port when the fitting is tightened. The tube end accepts instrument or hydraulic tubing via a double-ferrule compression mechanism. Together, these ends allow instrument tubing to be connected directly to SAE-ported valves, hydraulic pumps, cylinders, and manifold blocks without adapters or sealant tapes.

"SAE" refers to the Society of Automotive Engineers thread standard; "MS" refers to the Military Standard designation (MS16142) which defines the same straight-thread O-ring port system for aerospace and defence applications. Both refer to the same UNF straight thread with O-ring boss geometry — the terms are used interchangeably in industrial practice.

How the SAE O-Ring Boss (ORB) Seal Works


1
O-ring placement: An elastomeric O-ring (NBR standard; Viton optional) is seated in the machined groove on the male fitting's thread shoulder — just behind the start of the UNF threads.
2
Thread engagement: The straight UNF thread is screwed into the female SAE O-ring boss port on the valve, manifold, or cylinder. Straight threads engage without wedging — thread flanks carry mechanical load but do not seal.
3
O-ring compression: As the fitting is tightened, the O-ring groove shoulder moves toward the flat boss face of the female port. The O-ring is compressed axially between the fitting shoulder and the port face.
4
Seal formation: The O-ring deforms radially to fill the groove and seal against both the fitting shoulder and the port boss face simultaneously — creating a positive pressure seal from vacuum to full rated pressure.
5
Locknut (adjustable ORB): For orientation-adjustable variants, a back-up washer and locknut allow the fitting to be set at any rotational position before the locknut is tightened to compress the O-ring. This is the SAE J1926 "adjustable" port fitting — useful when the tube direction must be set after the fitting is threaded into the port.

SAE MS / O-Ring Boss vs Other Thread & Seal Systems


SystemThread TypeSealing MethodSealant Needed?Re-usable?Best For
SAE MS / ORBUNF straight (60°)O-ring axially compressed at port boss faceNo — O-ring seals dryYes — replace O-ringHydraulics, aerospace, industrial machinery
NPTTapered 60°Thread interference + sealant/tapePTFE tape requiredLimited — tape needed each timeGeneral piping, instrumentation
BSPT (Rc)Tapered 55°Thread interference + tapePTFE tape requiredLimitedUK / European piping
BSPP + Bonded SealParallel 55°Dowty seal at thread shoulder faceNo — seal included1–2 assemblies per sealEuropean instrumentation BSPP ports
ORFS (SAE J1453)UNF straightO-ring in cone-face groove; flat face contactNo — O-ring sealsYes — replace O-ringHigh-pressure hydraulics, OEM tubing
JIC 37° FlareUNF straight37° metal-to-metal flare contactNo — metal sealYesHydraulic tube & hose, fuel systems
⚠ SAE ORB vs ORFS — not interchangeable: SAE O-ring boss (ORB / MS16142 / SAE J1926) and O-ring face seal (ORFS / SAE J1453) are both straight UNF threads with O-ring seals, but the port geometry and O-ring groove location are different. ORB seals on a flat boss face with the O-ring on the fitting shoulder; ORFS seals on a machined cone face with the O-ring in a groove on the fitting face. Do not mix ORB fittings into ORFS ports or vice versa.

SAE MS Dash Size Reference


SAE and MS fittings are specified by dash size — a number that equals the nominal tube or port size in sixteenths of an inch. A -4 fitting = 4/16" = 1/4". The UNF thread size associated with each dash size is fixed by the standard.

Dash SizeTube OD (Inch)UNF Thread SizeO-Ring Size (AS568)Max Pressure (SS 316)
-21/8"5/16"-24 UNFAS568-9026 000 PSI
-41/4"7/16"-20 UNFAS568-9046 000 PSI
-63/8"9/16"-18 UNFAS568-9065 500 PSI
-81/2"3/4"-16 UNFAS568-9085 000 PSI
-105/8"7/8"-14 UNFAS568-9104 500 PSI
-123/4"1-1/16"-12 UNAS568-9124 000 PSI
-161"1-5/16"-12 UNAS568-9163 500 PSI
-201-1/4"1-5/8"-12 UNAS568-9203 000 PSI
-241-1/2"1-7/8"-12 UNAS568-9242 500 PSI
-322"2-1/2"-12 UNAS568-9322 000 PSI

Technical Specifications


ParameterDetails
BrandTES-LOK (Tesco Steel & Engineering)
Dash Size Range-2 through -32 (1/8" OD to 2" OD)
SAE/MS Thread EndStraight UNF / UN male thread per SAE J1926 / MS16142; O-ring groove behind threads
Tube EndDouble-ferrule compression — accepts instrument/hydraulic tubing OD from 1/8" to 2"
O-Ring MaterialNBR (Nitrile) — standard  |  Viton (FKM) — on request  |  EPDM — on request
Pressure RatingSS 316: up to 6 000 PSI (dash -4)  |  Carbon Steel: up to 6 000 PSI  |  Brass: up to 3 000 PSI
Temperature RangeSS 316: −196°C to 450°C  |  Carbon Steel: −40°C to 400°C  |  Brass: −40°C to 150°C  |  Limited by O-ring material
Body MaterialSS 304, SS 316 / 316L, Carbon Steel (1018 / 1215), Brass (CW617N), Inconel 625 (on request)
Ferrule MaterialMatched to body — SS 316 ferrules with SS body; Brass ferrules with Brass body
Thread StandardSAE J1926-1  |  ISO 11926-1  |  MS16142 (military)
O-Ring StandardAS568 (Imperial)  |  ISO 3601 (Metric equivalent)
Surface FinishPassivated (SS); zinc-plated or phosphate coated (Carbon Steel); bright zinc / nickel (Brass)
CertificationsISO 9001:2015  |  EN 10204 3.1 MTC on request  |  Hydrostatic test certification available

Material Selection Guide


MaterialMax TempCorrosion ResistanceTypical Application
Carbon Steel (1018)400°CModerate — requires protective coatingHydraulic power units, mobile equipment, industrial machinery
SS 304450°CGood — general corrosion resistanceFood, pharma, water-based fluid systems
SS 316 / 316L450°CExcellent — chloride resistantChemical processing, offshore, marine hydraulics
Brass (CW617N)150°CModerate — no ammonia or strong acidsHVAC, pneumatics, low-pressure hydraulics
Inconel 625650°COutstanding — high-temp oxidation & corrosionAerospace, high-temperature hydraulic circuits, defence

SAE MS Male Adapter — Configuration Types


ConfigurationTube EndSAE/MS EndOrientationBest For
Standard (Fixed) SAE Male AdapterDouble-ferrule compressionSAE ORB male — fixed positionFixed on assembly — set by thread engagementCompact assemblies where tube direction is predetermined
Adjustable SAE Male AdapterDouble-ferrule compressionSAE ORB male + back-up washer + locknutSwivels 360° before locknut tightenedInstrument racks — tube direction known only at installation
SAE Male Elbow Adapter (90°)Double-ferrule compressionSAE ORB male — 90° to tube axisFixed 90° anglePort access at right angle to tube run
SAE Male Elbow Adapter (45°)Double-ferrule compressionSAE ORB male — 45° to tube axisFixed 45° angleDiagonal port entry — lower pressure drop
Reducing SAE Male AdapterSmaller tube ODLarger SAE ORB threadStraightSmall instrument tube (1/4") into large SAE port (-12 or -16)

Why Choose TES-LOK SAE MS Male Adapters?


🛠 Precision-Machined O-Ring Groove

The O-ring groove width, depth, and corner radii are held to SAE J1926 tolerances — ensuring correct O-ring compression (15–25% squeeze) without cutting or extruding the O-ring. Under-depth grooves cause low squeeze and leakage; over-depth grooves cause O-ring extrusion and failure under pressure cycling.

✅ SAE J514 + MS16142 Dual Compliance

TES-LOK SAE MS adapters are manufactured to comply with both SAE J514 / J1926 (commercial hydraulic standard) and MS16142 (US military standard) — enabling use on both commercial industrial projects and defence / aerospace specifications from the same part number.

🎯 Zero-Leak O-Ring Seal — No Tape, No Compound

The elastomeric O-ring provides a positive, positive-pressure, positive-vacuum seal without PTFE tape, anaerobic compounds, or pipe sealant. No contamination risk to hydraulic fluid. No cure time. Immediate pressure-test after assembly.

🔍 Adjustable Port Orientation

The adjustable variant (locknut type) allows the fitting body to be rotated to any position before the locknut is tightened — a critical advantage when tube routing must be determined after the fitting is threaded into the valve port. No need to remove and re-install the fitting to change tube direction.

📦 Full Dash-Size Matrix in Stock

Dash -4 through -16 in SS 316 and Carbon Steel maintained ex-stock in Mumbai. Dash -20, -24, -32 and special alloys (Inconel) manufactured to order with 2–3 week lead time. Single-source procurement for complete hydraulic and instrumentation skid bills of material.

🌟 ISO 9001:2015 with EN 10204 3.1 MTC

Full material traceability from mill certificate to finished fitting. Hydrostatic testing at 1.5× rated pressure available per batch. Dimensional inspection reports per SAE J1926 thread gauging. Suitable for EPC contractor and owner-operator QA/QC requirements.

Installation Guide


1
Identify the port type: Confirm the female port is an SAE O-ring boss (ORB / SAE J1926) port — a flat-faced boss with a straight UN/UNF thread. Do not use an SAE MS adapter in an NPT, BSPT, JIC, or ORFS port — the thread pitch and sealing geometry are incompatible.
2
Inspect the O-ring: Check the O-ring for cuts, nicks, or flat spots. Lightly lubricate with clean system fluid (petroleum-based systems: mineral oil; water-glycol hydraulic fluid: use compatible lubricant). Do not use silicone grease on NBR O-rings — it can cause swelling.
3
Seat the O-ring in the groove: Roll the O-ring into the groove until it sits evenly in the full circumference. Ensure no twisting — a twisted O-ring will extrude under pressure.
4
Thread into port by hand: For fixed adapters — thread in by hand until O-ring contacts the port boss face, then tighten to the specified torque. For adjustable adapters — back the locknut off fully, thread fitting in until O-ring contacts boss, back off 1–1.5 turns, position fitting to desired tube direction, then tighten the locknut to specification.
5
Tighten to torque: Use a torque wrench. Over-tightening extrudes the O-ring into the thread space and damages both the fitting and the port. See the torque table below. Hold the fitting body with a back-up wrench — do not allow the fitting to rotate after tube connection.
6
Connect the compression tube end: Insert cut and deburred tube through back nut and ferrule(s). Push to full depth in the fitting body. Hand-tighten the compression nut and then make 1¼ turns from finger-tight to swage the ferrules.
7
Leak test: Pressurise to 1.5× working pressure with nitrogen or system fluid. Check the O-ring boss joint with leak detection fluid or by visual inspection of the port boss area. Zero bubbles / zero weeping over 60 seconds confirms a good seal.

Recommended Tightening Torque — SAE O-Ring Boss (Fixed Adapter)


Dash SizeUNF ThreadTorque — Steel Body (Nm)Torque — SS 316 Body (Nm)Torque — Brass Body (Nm)
-47/16"-2012–16 Nm14–18 Nm9–12 Nm
-69/16"-1820–26 Nm22–28 Nm14–18 Nm
-83/4"-1634–42 Nm36–44 Nm22–28 Nm
-107/8"-1447–57 Nm50–60 Nm30–38 Nm
-121-1/16"-1261–75 Nm65–80 Nm40–50 Nm
-161-5/16"-1295–115 Nm100–120 Nm60–75 Nm
⚠ O-ring extrusion from over-torque: Exceeding the recommended torque on an ORB fitting pushes the O-ring into the thread engagement zone, shearing and extruding rubber into the hydraulic circuit. This contaminates downstream components and causes immediate or delayed seal failure. Always use a calibrated torque wrench on SAE O-ring boss connections.

Industry Applications


IndustryTypical Use PointWhy SAE MS Preferred
Hydraulic Power UnitsPump outlet / inlet instrument tapping points, actuator port connections, valve manifold SAE portsSAE ORB ports are the dominant standard on hydraulic valves and cylinders worldwide — direct fit without adapters
Mobile & Construction EquipmentExcavator hydraulic circuits, crane slew circuits, loader valve banksSAE/MS connections resist vibration and shock loads better than NPT; no thread loosening over time
Aerospace & DefenceAircraft hydraulic systems per MS16142; armoured vehicle hydraulic actuators; missile hydraulic actuatorsMS16142 military qualification; material certs to AS/EN standards; traceable heat numbers
Oil & GasSubsea BOP hydraulic control systems, wellhead accumulator instrument connectionsSS 316 body resists salt water; O-ring seal provides reliability in vibrating wellhead environments
Industrial MachineryInjection moulding machine hydraulics, metal-forming press circuits, CNC machine tool hydraulic portsSAE ORB is the standard port on most industrial hydraulic valves; no conversion needed
Power GenerationSteam turbine governing hydraulics, lube oil system instrument connectionsSS 316 body + Viton O-ring tolerates turbine oil temperatures above 100°C
Automotive & Test RigsVehicle hydraulic brake test rigs, powertrain test bench instrument connectionsSAE J514 compliance ensures traceability in automotive OEM and test environments
Shipbuilding / MarineBow thruster hydraulics, deck crane hydraulic circuits, hatch actuator control portsSS 316 body resists marine atmosphere; SAE ORB connections standard on marine hydraulic components

Frequently Asked Questions


Q1. What is the difference between SAE O-ring boss (ORB) and O-ring face seal (ORFS)?

Both use straight UNF threads and an O-ring seal, but the geometry differs fundamentally. ORB (SAE J1926 / MS16142): the O-ring sits in a groove on the fitting shoulder and seals against the flat boss face of the female port. ORFS (SAE J1453): the O-ring sits in a groove machined into the fitting face and seals against a machined cone face in the female port. ORB ports and ORFS ports are not interchangeable — the fitting must match the port type exactly.

Q2. How do I identify an SAE O-ring boss port on a hydraulic valve?

An SAE ORB port has a flat-faced machined boss area around the port hole, a visible chamfer at the port entry, and a straight UN/UNF thread. It does not taper. There is no O-ring groove in the port face itself (the groove is on the fitting, not the port). Compare with: NPT/BSPT ports taper noticeably when you look down the bore; ORFS ports have a cone-shaped internal chamfer. If the port is flat-faced with a straight thread, it is most likely SAE ORB — confirm the thread pitch against the SAE J1926 dash size chart.

Q3. What O-ring material should I specify for hydraulic oil service?

For mineral-oil-based hydraulic fluids (ISO 46, ISO 68, HV 46), specify NBR (Nitrile) — the standard option. For synthetic hydraulic fluids (phosphate ester, water-glycol, polyol ester), specify Viton (FKM). For water-based fluids and biodegradable esters, EPDM is suitable. Always verify the O-ring compatibility with the specific fluid formulation — fluid additive packages can affect elastomer compatibility even within the same base fluid type.

Q4. Can an SAE MS male adapter be used on a JIC 37° flare port?

No. JIC 37° flare connections (SAE J514 JIC) use the same UNF thread sizes as ORB, but the sealing mechanism is completely different — the JIC fitting has a 37° flared nose that seals against a matching 37° cone seat in the port. An ORB fitting screwed into a JIC port will not have O-ring contact with any sealing surface and will leak. Always verify the port type before selecting the adapter end configuration.

Q5. What is the "adjustable" SAE male adapter and when should I use it?

An adjustable SAE male adapter (also called "SAE adjustable port adapter") has a back-up washer and a separate jam/locknut on the thread behind the O-ring groove. Thread the fitting into the port until the O-ring contacts the boss face, then back off 1–1.5 turns. Rotate the fitting body to point the tube outlet in the desired direction, then tighten the locknut to compress the O-ring and lock the position. Use when tube routing direction is determined after the fitting is already in the port — avoids having to remove and re-thread the fitting to change orientation.

Q6. What does the dash number mean in SAE MS fittings — e.g. dash -8?

The dash number equals the nominal tube OD in sixteenths of an inch. Dash -8 = 8/16" = 1/2" tube OD. This also corresponds to a specific UNF thread size (3/4"-16 UNF for -8), a specific O-ring groove size (AS568-908), and a specific wrench hex size. All dimensions are fixed by the SAE J1926 / MS16142 standard for each dash size.

Q7. Are TES-LOK SAE MS adapters interchangeable with Parker or Swagelok SAE fittings?

Yes for the SAE ORB thread end — TES-LOK adapters are manufactured to SAE J1926 / MS16142 dimensional standards, so the thread end will engage correctly with any SAE-compliant female port regardless of the original port manufacturer. For the compression tube end: TES-LOK uses the same double-ferrule geometry as industry-standard systems and ferrules are dimensionally interchangeable, though TES-LOK recommends using TES-LOK ferrule sets with TES-LOK bodies for certified performance.

Q8. Do you supply material test certificates for SAE MS male adapters?

Yes. EN 10204 3.1 material test certificates are available for SS 304, SS 316, and Inconel 625 bodies. Carbon steel and Brass adapters are supplied with EN 10204 2.1 compliance certificates as standard; 3.1 certificates are available on request. Hydrostatic test certificates and dimensional inspection reports per SAE J1926 gauging are available for project orders.