Tube Male Connector Manufacturer, Supplier & Exporter
A male connector joins instrumentation tubing to a female-threaded port. It has a tube compression end on one side and a male NPT, BSPT or BSPP thread on the other. Raaj Fittings manufactures and exports male connectors in double ferrule and single ferrule designs, in SS 316L, SS 304, duplex, super duplex and nickel alloys, in every common tube size and thread size.
Male connectors are the link between tubing and equipment. They screw into valves, manifolds, transmitters, gauges, pumps, cylinders and process connections, and accept the tube on the other side — making them one of the most frequently used fittings in any instrument installation.
All male connectors are supplied with EN 10204 3.1 mill test certificates and full material traceability.
We export male connectors to instrumentation contractors, OEMs and distributors across the Middle East and GCC, Europe and the Americas, in metric and imperial tube sizes with NPT or BSP ends to suit each market.
Male Connector Specifications
Metric 3–25 mm; imperial 1/8"–1"
1/8" to 1" in NPT, BSPT and BSPP; tube OD and thread size can be combined independently
NPT to ASME B1.20.1; BSPT and BSPP to BS 21 / ISO 7-1
Double ferrule and single ferrule compression; DIN 2353 bite type on request
Double ferrule up to 413 bar (6,000 psi); single ferrule up to 207 bar (3,000 psi), depending on size, wall and material
BSPP ends seal with a bonded washer or elastomer seal against the port face
EN 10204 3.1 mill test certificate; EN 10204 3.2 on request
Materials & Grades
We supply male connectors in the following materials and grades. All grades are supplied with EN 10204 3.1 / 3.2 Mill Test Certificates.
Stainless Steel Male Connectors
Stainless steel is the standard material for instrumentation tube fittings across oil and gas, petrochemical, pharmaceutical, and offshore applications. SS 316L is the most widely specified grade.
The industry default for instrumentation tube fittings — low carbon content prevents sensitisation; molybdenum addition provides superior chloride and acid resistance versus 304 grades.
Superior chloride and acid resistance — used where chloride exposure, marine atmosphere, or mild chemical service requires better corrosion resistance than 304.
General corrosion resistance at lower cost than 316L — suitable for water, steam, mild chemical, and food-grade applications where chloride exposure is limited.
Duplex & Super Duplex Stainless Steel Male Connectors
Duplex and super duplex grades provide approximately twice the yield strength of 316L with excellent resistance to chloride stress corrosion cracking — the preferred choice for offshore and subsea instrumentation where standard 316L may be susceptible to SCC.
(UNS S31803 / S32205) Offshore topsides instrumentation, seawater injection, and chemical injection systems
(UNS S32750) Subsea instrumentation, high-chloride offshore service, and FPSOs — PREN ≥ 42
Nickel Alloy Male Connectors
For aggressive chemical, sour gas, and high-temperature service where duplex stainless steel is insufficient — specified in chemical injection, downhole instrumentation, and severe process environments.
(UNS N06625) Outstanding corrosion resistance in offshore, subsea, and chemical service; widely specified for downhole instrumentation and subsea chemical injection tubing
(UNS N10276) Broad-spectrum resistance to aggressive acids, chlorides, and oxidising media; chemical and FGD process sample systems
(UNS N04400) Hydrofluoric acid service, seawater, and marine instrumentation systems
(UNS N08020) Sulfuric acid and aggressive chemical process sample and instrumentation systems
Special Grades & High-Purity Male Connectors
For semiconductor, pharmaceutical, and high-purity gas applications requiring electropolished internal surfaces and ultra-low extractable contamination.
Pharmaceutical and biotech grade — electropolished internal surface for sterile process piping, pure steam, WFI, and clean compressed air systems in GMP-compliant facilities.
Semiconductor grade — ultra-high-purity electropolished finish for process gas delivery, specialty gas distribution, and wet chemistry in semiconductor fabs.
Exceptional corrosion resistance in seawater and oxidising media at low density — used in desalination and marine instrumentation where weight is a factor.
Choosing the Thread
The threaded end must match the port it screws into. The three common forms are:
- NPT — 60° tapered thread, sealed on the thread flanks with PTFE tape or sealant. Standard on most instruments and on US and international oil and gas projects.
- BSPT — 55° tapered thread, also sealed on the threads; common in Europe, the Middle East and Asia.
- BSPP — 55° parallel thread that does not seal on the threads; the seal is made on the port face with a bonded washer or elastomer seal.
NPT and BSP threads look similar but are not interchangeable. Always confirm the port thread before ordering.
Tube Size and Thread Size
The tube OD and the thread size are chosen separately, so a 1/4" tube can connect to a 1/2" NPT port, for example. Where the port is male rather than female, use a female connector. To join two tubes, use a union connector, and to adapt between different threads or sizes, see our reducing unions and adapters.
Installation Tips
Fit and tighten the threaded end into the port first, then install the tube. For tapered threads, apply sealant suitable for the fluid and temperature, keeping it off the first thread to avoid contaminating the system. Hold the body hex while tightening the tube nut so the threaded joint is not disturbed.
Applications & Industries
- Transmitter, gauge and switch connections
- Instrument valve and manifold connections
- Hydraulic cylinders, pumps and control valves
- Analyser and sample system components
- Chemical injection pumps and quills
For stainless steel compression fittings, use annealed seamless or welded-and-drawn tubing of suitable hardness and a wall thickness chosen for the working pressure. Male connectors are frequently ordered in quantity with matching unions, elbows and tees for complete instrument hook-ups, and can be supplied cleaned and bagged for oxygen or high-purity service when specified.
When ordering, give the tube OD, thread size and type, fitting design and material grade — for example 1/4" OD × 1/2" NPT male connector, double ferrule, SS 316L. See all tube fittings.
Testing, Inspection, Marking & Packing
Male connectors are produced under our quality assurance process:
- Bar stock verified by PMI testing, with full traceability
- Thread gauging of NPT, BSPT and BSPP ends
- Dimensional inspection of tube seat, bore and hex sizes
- Pressure testing on request
- Marking with material grade and heat code
Supplied with EN 10204 3.1 mill test certificates; EN 10204 3.2 certificates and third-party inspection on request.
Fittings are capped and bagged to keep ports clean, then boxed and packed in seaworthy wooden cases for export; marking, tagging and packing to your specification are available on request.
Why Choose Raaj Fittings for Male Connectors?
Raaj Sagar Steels has supplied piping components since 2003 and today manufactures tube fittings at two plants in India for buyers in the Middle East, Europe and the Americas.
- Manufactured in-house — Male connectors are made in our own plants, so material, dimensions and delivery stay under our control.
- Ready stock, short lead times — common sizes and grades are held in stock for prompt dispatch; other sizes, grades and specials are manufactured to order.
- Certified quality — ISO 9001:2015, ISO 14001:2015 and ISO 45001:2018 certified; PED 2014/68/EU supply available, and NACE MR0175 / ISO 15156 material on request.
- 100% material verification — PMI testing on incoming material and EN 10204 3.1 mill test certificates with every order; 3.2 certificates on request.
- Third-party inspection ready — we regularly work with SGS, Bureau Veritas, TÜV and DNV.
- Export documentation — MTCs, certificates of origin, packing lists and inspection reports to suit projects in the GCC, Europe and the Americas.
- Export packing — seaworthy packing with end and face protection, and packing to your specification on request.
- Fast response — our team replies to enquiries within one business day.
Male Connectors — FAQs
A male connector is a tube fitting with a compression end for tubing on one side and a male threaded end on the other, used to connect tubing to a female-threaded port.
NPT to ASME B1.20.1, and BSPT and BSPP to BS 21 / ISO 7-1, in sizes from 1/8" to 1".
Yes. Tube OD and thread size are chosen independently — for example a 6 mm tube with a 1/2" NPT thread.
BSPP is a parallel thread, so it seals on the port face using a bonded washer or elastomer seal, not on the threads.
No. They have different thread angles and pitches and will not seal reliably if mixed.
Yes. We supply male connectors for projects under the European Pressure Equipment Directive (PED 2014/68/EU), with EN 10204 3.1 certificates as standard and 3.2 on request. NACE MR0175 / ISO 15156 compliant material is available for sour service in the Middle East and the Americas.
