ISO 9001:2015 Certified

'SHAPING INDUSTRIES WITH THE FINEST STEEL'

High Pressure Fitting Manufacturer

TES-LOK high-pressure fittings — cone-and-thread medium-pressure (MP) and high-pressure (HP) fittings for heavy-wall tube in waterjet cutting, oil & gas well testing, chemical injection, hydrogen, and high-pressure test rigs. Engineered to seal far beyond instrument-grade fittings, with glands, collars, and anti-vibration design. SS 316, Inconel, Monel, Hastelloy, Carbon Steel. Up to 60,000 PSI (4137 bar). −73°C to 315°C. ISO 9001:2015 certified. Made in India.

Cone-and-Thread MP / HP Up to 60,000 PSI (4137 bar) Heavy-Wall Tube SS 316 / Inconel / Monel Hastelloy / Carbon Steel −73°C to 315°C Gland & Collar Design ISO 9001:2015
High Pressure Cone and Thread Fittings

TES-LOK High Pressure Fittings

High Pressure Needle Valve

High Pressure Needle Valve (Related)

Instrumentation Tube Fittings

Instrumentation Tube Fittings

What Is a High Pressure Fitting?


Definition: A High Pressure Fitting is a tube/pipe connection engineered to seal and grip at pressures far beyond standard instrument fittings — up to 60,000 PSI (4137 bar). The high-pressure (HP) and medium-pressure (MP) ranges use a cone-and-thread connection: the heavy-wall tube end is coned (machined to a cone) and threaded, and a separate gland and collar draw the coned tube against the fitting's matching seat to form a metal-to-metal seal under enormous clamping force. Heavy-wall, small-bore tube, oversized threads, and large sealing areas let these fittings contain pressures that would burst ordinary compression or bite-type fittings. They are the standard for waterjet, well-testing, chemical-injection, hydrogen, and high-pressure laboratory and test-rig systems.

High-pressure fittings are supplied in pressure classes — typically Medium Pressure (MP) to around 20,000 PSI and High Pressure (HP) to around 60,000 PSI — each with its own coning angle, thread, gland, and collar dimensions and matching heavy-wall tube. TES-LOK manufactures the full range of high-pressure connectors, elbows, tees, crosses, adapters, and glands & collars, plus matching high-pressure needle valves.

How the Cone-and-Thread Connection Seals


1
Cone the tube: The heavy-wall tube end is machined (coned) to the specified cone angle using a coning tool.
2
Thread the tube: External threads are cut on the tube OD behind the cone to receive the gland nut.
3
Fit gland & collar: A collar (threaded sleeve) is threaded onto the tube; the gland nut sits behind it, ready to drive the assembly into the fitting.
4
Metal-to-metal cone seal: Tightening the gland nut drives the coned tube end hard against the fitting's matching female cone seat, forming a high-integrity metal-to-metal seal that intensifies as pressure rises.
5
Reusable & serviceable: The cone and threads stay on the tube, so the joint can be disconnected and remade many times — essential on high-pressure test rigs and injection systems.

High Pressure Fitting Pressure Classes


ClassTypical RatingTubeTypical Use
Medium Pressure (MP)Up to ~20,000 PSI (1379 bar)Coned & threaded heavy-wallWell testing, chemical injection, general HP process
High Pressure (HP)Up to ~60,000 PSI (4137 bar)Coned & threaded heavy-wall, small boreWaterjet cutting, HP test rigs, autoclaves, research
Instrument Compression (ref.)Up to ~6,000 PSI (414 bar)Standard-wall tube, twin-ferruleGeneral instrumentation (see tube-fitting range)

High Pressure vs Standard Instrument Fittings


CriterionHigh Pressure (Cone-and-Thread)Instrument (Twin-Ferrule / Bite)
PressureUp to 60,000 PSI (4137 bar)Up to ~6,000 PSI (414 bar)
TubeHeavy-wall, small-bore, coned & threadedStandard-wall, cut & deburred
SealConed tube on female seat, metal-to-metalFerrule on tube OD / cutting ring
Tube prepConing + threading (special tools)Square cut + deburr only
ComponentsBody, gland, collarBody, ferrule(s), nut
Best forWaterjet, well testing, chemical injection, HP researchInstrumentation, analyser, process measurement
⚠ Use the matched MP/HP series & correct heavy-wall tube: High-pressure cone-and-thread fittings must be used with the matching pressure-class gland, collar, body, and the correct coned-and-threaded heavy-wall tube. Do not substitute instrument tube, mix MP and HP components, or use standard-wall tube — at these pressures, a mismatch is a serious safety hazard. Coning and threading must be done with the correct tooling to the specified dimensions.

High Pressure Fitting Range


CategoryFittings
Connectors & AdaptersMale / female HP connectors • MP/HP adapters • tube-to-NPT and tube-to-pipe adapters
Elbows90° and 45° high-pressure elbows
Tees & CrossesHP tees, crosses, and branch fittings
Glands & CollarsCone-and-thread glands and collars (per pressure class & tube size)
Couplings & UnionsStraight couplings, reducer couplings, bulkhead unions
ValvesHigh Pressure Needle Valves • HP relief / bleed valves

Technical Specifications


ParameterDetails
BrandTES-LOK (Tesco Steel & Engineering)
TypeCone-and-thread MP / HP fittings (gland & collar)
Tube OD Range1/4" to 1" heavy-wall (MP/HP)  |  small-bore for highest pressures
Working PressureMP: up to ~20,000 PSI (1379 bar)  |  HP: up to 60,000 PSI (4137 bar)
Working Temperature−73°C to 315°C (−100°F to 600°F) — material dependent
ConnectionConed-and-threaded tube end with gland & collar; NPT / pipe adapter ends available
Body MaterialSS 316 / 316L, SS 304, Carbon Steel, Monel, Inconel, Hastelloy, special alloys
SealMetal-to-metal coned seat (pressure-energised)
ShapesConnectors, adapters, elbows, tees, crosses, couplings, unions, glands & collars
CertificationsISO 9001:2015  |  EN 10204 3.1 MTC on request  |  NACE MR0175 on request

Material Selection Guide


MaterialMax TempCorrosion / ServiceTypical High-Pressure Use
SS 316 / 316L315°CExcellent — chloride resistantGeneral HP, waterjet, chemical injection
SS 304 / 304L315°CGood — general serviceWater and mild HP media
Carbon / Alloy Steel315°CCoated; high strengthHP hydraulic and test-rig service
Monel 400315°CExcellent — HF, seawaterHF and sour high-pressure service
Inconel 625 / 718315°C+Outstanding — sour & high-strengthSour gas, well testing, subsea HP
Hastelloy C-276315°CSuperior — strong acidsHP acid and halogen injection

Why Choose TES-LOK High Pressure Fittings?


🔥 Pressures to 60,000 PSI

The cone-and-thread MP/HP design seals at pressures far beyond instrument fittings — up to 60,000 PSI (4137 bar) — for the most demanding waterjet, well-testing, and high-pressure research applications.

🔧 Pressure-Energised Metal Seal

The coned tube seats metal-to-metal against the fitting, and the seal intensifies as system pressure rises — a self-energising joint with no elastomer to fail, ideal for extreme-pressure and high-cycle service.

🧬 Sour & Corrosive Alloys

Available in Inconel, Monel, and Hastelloy with NACE MR0175 compliance for sour gas, HF, and aggressive chemical-injection service at high pressure — where SS alone is not enough.

♻ Reusable & Serviceable

The cone and threads remain on the tube, so connections can be broken and remade many times — essential for test rigs, injection skids, and systems that are frequently reconfigured.

📦 Complete HP Range

Connectors, adapters, elbows, tees, crosses, couplings, unions, glands & collars, and matching high-pressure needle valves — the full high-pressure system from a single source.

🌟 ISO 9001:2015 & Full Traceability

Manufactured under ISO 9001:2015 with EN 10204 3.1 MTC and PMI available — full material traceability for the safety-critical nature of high-pressure service.

Cone-and-Thread Assembly Guide


1
Select matched components & tube: Confirm the pressure class (MP or HP), and use the matching body, gland, collar, and correct coned-and-threaded heavy-wall tube. Never mix classes or use standard instrument tube.
2
Cut & square the tube: Cut the heavy-wall tube square and remove burrs. Tube must be clean and within specified OD/wall tolerance.
3
Cone and thread the end: Using the correct coning and threading tools, machine the cone and external thread on the tube end to the specified dimensions. Inspect the cone for a clean, concentric finish.
4
Fit collar & gland: Thread the collar onto the tube and place the gland nut behind it. Lightly lubricate threads with the recommended HP anti-seize.
5
Make up to the seat: Insert the coned tube into the fitting and tighten the gland nut to the recommended torque, driving the cone hard onto the female seat. Use a back-up wrench on the body.
6
Proof test: Pressure-test to the specified proof pressure (above working pressure) behind a guard, following the safe-test procedure for high-pressure systems, before placing in service.
⚠ High-pressure systems are hazardous — follow safe practice: Stored energy at 60,000 PSI is extremely dangerous. Only trained personnel should assemble, test, and operate high-pressure fittings, using guards, correct tooling, matched components, and approved procedures. Always depressurise and verify zero pressure before breaking any joint.

Industry Applications


IndustryTypical Use PointWhy High Pressure Fittings
Waterjet CuttingUltra-high-pressure waterjet and abrasive-jet lines60,000 PSI cone-and-thread joints withstand UHP waterjet service
Oil & Gas Well TestingSurface well-test, flowback, and pressure-control linesMP/HP fittings with Inconel/Monel for sour, high-pressure well fluids
Chemical InjectionHP chemical and methanol injection skidsHastelloy / Monel cone-and-thread for corrosive HP injection
Hydrogen & CNGHigh-pressure hydrogen and gas test/fuelling systemsMetal-to-metal seal for HP gas; no elastomer permeation
Research & Test RigsHigh-pressure laboratory, autoclave, and test-bench systemsReusable, reconfigurable HP connections for research
Power & ProcessHigh-pressure sampling and analyser linesHP integrity on small-bore high-pressure taps
Subsea & OffshoreHP control, injection, and well-intervention linesInconel/Monel HP fittings for sour subsea HP service
Defence & AerospaceHigh-pressure test and propellant systemsTraceable, high-integrity HP connections

Frequently Asked Questions


Q1. What is a high pressure fitting?

A high pressure fitting is a tube connection engineered to seal at pressures far above instrument fittings — up to 60,000 PSI (4137 bar). It uses a cone-and-thread design: the heavy-wall tube end is coned and threaded, and a gland and collar drive the coned tube against the fitting's matching seat for a metal-to-metal seal. It is used in waterjet, well testing, chemical injection, hydrogen, and high-pressure research.

Q2. What is the difference between MP and HP fittings?

MP (medium pressure) cone-and-thread fittings are typically rated to around 20,000 PSI (1379 bar), and HP (high pressure) fittings to around 60,000 PSI (4137 bar). They differ in coning angle, thread, gland/collar dimensions, and tube wall. MP and HP components are not interchangeable — select the class for your working pressure and use the matching tube and parts.

Q3. How is a high pressure fitting different from a standard instrument tube fitting?

An instrument tube fitting (twin-ferrule or bite-type) grips a standard-wall tube with a ferrule or ring and is rated to about 6,000 PSI. A high pressure fitting uses a coned-and-threaded heavy-wall tube with a gland and collar, sealing metal-to-metal against a seat, and is rated up to 60,000 PSI. HP fittings need special coning/threading tooling and heavy-wall tube; instrument fittings need only a square, deburred cut.

Q4. What does "cone-and-thread" mean?

Cone-and-thread describes how the tube is prepared: the tube end is machined to a cone, and an external thread is cut behind the cone. A collar threads onto the tube and a gland nut drives the coned end against the fitting's female seat. The metal-to-metal cone seal is pressure-energised — it seals tighter as pressure rises — which is why it can contain extreme pressures.

Q5. What pressure and temperature can these fittings handle?

TES-LOK high-pressure fittings cover up to 60,000 PSI (4137 bar) for the HP class and around 20,000 PSI for MP, with a temperature range of about −73°C to 315°C (−100°F to 600°F) depending on material. The all-metal cone seal has no elastomer, so performance is governed by the body material and tube.

Q6. What materials are available for sour and corrosive high-pressure service?

For sour (H₂S) and corrosive HP service, choose Inconel 625/718, Monel 400, or Hastelloy C-276 with NACE MR0175 / ISO 15156 compliance. SS 316 suits general HP and waterjet service. The material must be selected for both the high pressure and the specific fluid — contact our team with your pressure, temperature, and media.

Q7. Do high pressure fittings need special tube and tooling?

Yes. They require heavy-wall, small-bore tube of the correct grade, and the tube end must be coned and threaded using the correct coning and threading tools to the specified dimensions. Standard instrument tube and ordinary tools cannot be used. Using the correct tube and tooling is essential for safety at high pressure.

Q8. Do you also supply high pressure valves?

Yes. TES-LOK manufactures matching high-pressure needle valves and HP relief/bleed valves alongside the fitting range, so a complete high-pressure system — fittings, glands, collars, and valves — comes from a single source. See the sidebar for related products.