Stainless Steel Instrumentation Fittings

A stainless steel tube fitting is a precisely designed connector used to join, redirect, or terminate stainless steel tubes in fluid and gas systems. Commonly referred to as SS tube fittings. These fittings consist of iron-chromium alloys (10.5–30% chromium) with added nickel, molybdenum, and manganese to improve corrosion resistance and strength. SS tube fittings have a tensile strength between 515 and 860 MPa and working temperatures from -196°C to 870 °C. These fittings provide leak-free performance even in tough conditions. Their key benefits are excellent corrosion resistance, the ability to handle high pressures up to 10,000 psi, and chemical compatibility, which makes them essential in the oil and gas, pharmaceutical, chemical processing, & power generating industries.

Stainless Steel Tube Fittings Prices

Stainless steel tube fitting price depends on 5 variables, i.e, grade, size, connection type, certification, and order volume.

Approximate Price Range

Stainless steel tube fittings are priced between Rs 250 and Rs 1,875 per piece in the Indian market. High-alloy variants such as 904L or SMO 254 fall at the higher end of the range. Bulk procurement from SS tube fittings manufacturers in India brings per-unit costs down considerably.

Factors Affecting Price

The price of stainless steel tube fittings is determined by five factors, i.e, material grade, size, connection type, certification, and order quantity. The grades like 316L, 317L, and 904L are more expensive than 304 due to their higher alloy content. Larger diameters and thicker walls cost more, as they require more material. Compression and push-to-connect fittings are usually costly as they need precise machining. Extra testing and certifications add to the cost, while bulk orders lower the price per piece.

Stainless Steel Tube Fittings Grades

The stainless steel tube fittings are available in a wide range of grades to suit different operating and service conditions.

Stainless Steel SMO 254 Tube Fittings
Stainless Steel 446 Tube Fittings
Stainless Steel 316 Tube Fittings
Stainless Steel 310H Tube Fittings
Stainless Steel 304L Tube Fittings
Stainless Steel 347H Tube Fittings
Stainless Steel 348 Tube Fittings
Stainless Steel 348H Tube Fittings
Stainless Steel 321 Tube Fittings
Stainless Steel 904L Tube Fittings
Stainless Steel 304H Tube Fittings
Stainless Steel 316L Tube Fittings
Stainless Steel 316H Tube Fittings
Stainless Steel 316LN Tube Fittings
Stainless Steel 317L Tube Fittings
Stainless Steel 309H Tube Fittings
Stainless Steel 304LN Tube Fittings
Stainless Steel 304N Tube Fittings
Stainless Steel 321H Tube Fittings
Stainless Steel 304 Tube Fittings
Stainless Steel 316N Tube Fittings
Stainless Steel 310 Tube Fittings
Stainless Steel 317 Tube Fittings
Stainless Steel 347 Tube Fittings
Stainless Steel 310MoLn Tube Fittings

Types Of Stainless Steel Tube Fittings

Stainless steel tube fittings are available in various types to match the exact metallurgical and service requirements of each application.

Compression fittings
Welded fittings (butt weld/socket weld)
Threaded fittings
Flared fittings
Push-to-connect fittings

Stainless Steel Tube Fittings Specifications

The table below outlines the standard stainless steel tube fittings dimensions, material grades, pressure ratings, and construction parameters used in industrial procurement.

Parameter	Specification
Material grades	Stainless steel 304, 304L, 316, 316L, and other corrosion-resistant stainless grades
Product type	Tube fittings for instrumentation and process tubing connections
Standard/specification	ASTM A269 for tubing compatibility; fittings commonly supplied for stainless steel tube systems
Connection types	Compression, threaded, weld, and instrumentation-style connections
Size range	1/8" to 2" for common instrumentation tube fittings; metric sizes also available from 3 mm to 50 mm
Tube compatibility	Used with stainless steel tubing in OD-based sizes rather than pipe schedules
Pressure rating	Commonly 3,000 psi to 10,000 psi for tube fittings
Construction	Seamless, precision-machined fittings designed for leak-tight service
Typical applications	Instrumentation lines, chemical processing, process control, and corrosive service
Testing/quality	Full certification, traceability, and dimensional tolerance control are commonly provided

Stainless Steel Tube Fittings Size Chart

The sizing chart below provides stainless steel tube fitting dimensions by tube OD, wall thickness range, and approximate weight per metre to help in material selection.

Tube OD	Wall thickness range	Approx. weight per meter	Typical fitment range
6 mm	0.5 to 1.2 mm	0.069 to 0.144 kg/m	Instrumentation tube fittings
9.52 mm	0.5 to 1.2 mm	0.112 to 0.249 kg/m	Instrumentation tube fittings
10 mm	0.5 to 1.2 mm	0.119 to 0.264 kg/m	Instrumentation tube fittings
12.7 mm	0.5 to 1.2 mm	0.153 to 0.345 kg/m	Instrumentation tube fittings
14 mm	0.5 to 1.2 mm	0.169 to 0.384 kg/m	Instrumentation tube fittings
15.87 mm	0.5 to 2.0 mm	0.192 to 0.694 kg/m	Instrumentation tube fittings
19 mm	0.5 to 3.0 mm	0.231 to 1.200 kg/m	Instrumentation tube fittings
25 mm	0.5 to 3.6 mm	0.306 to 1.926 kg/m	Common tube fittings
25.4 mm	0.5 to 3.6 mm	0.311 to 1.962 kg/m	Common tube fittings
31.8 mm	1.2 to 3.6 mm	0.918 to 2.538 kg/m	Larger tube fittings
38 mm	1.2 to 3.6 mm	1.104 to 3.096 kg/m	Larger tube fittings
44.5 mm	1.2 to 3.6 mm	1.299 to 3.681 kg/m	Larger tube fittings
50.8 mm	1.2 to 3.6 mm	1.488 to 4.248 kg/m	Larger tube fittings
63.5 mm	1.6 to 3.6 mm	2.476 to 5.391 kg/m	Heavy-duty tube fittings
76.1 mm	1.6 to 3.6 mm	2.980 to 6.525 kg/m	Heavy-duty tube fittings
101.6 mm	1.6 to 3.6 mm	4.000 to 8.820 kg/m	Heavy-duty tube fittings

Schedule Chart Of Stainless Steel Tube Fittings

Match the schedule below to your wall thickness requirement and OD range before specifying a stainless steel tube fitting for pressure or service class.

Schedule	Typical wall thickness	Common tube OD range
Schedule 5S	Light wall	1/8" to 2" tube systems
Schedule 10S	Light to medium wall	1/8" to 2" tube systems
Schedule 40S	Standard wall	Common stainless tube systems
Schedule 80S	Heavy wall	Common stainless tube systems
Schedule 100	Extra heavy wall	Larger duty tubing applications
Schedule 120	Heavy wall	Larger duty tubing applications
Schedule 140	Very heavy wall	Larger duty tubing applications
Schedule 160	Extra heavy wall	Higher-pressure tubing applications
XXH / XXS	Maximum wall thickness	Severe service tubing applications

Key Features Of Stainless Steel Tube Fittings

The 9 key features set stainless steel tube fittings apart from standard carbon steel or brass alternatives in critical service applications.

Corrosion resistance
High strength
Temperature tolerance
Precision and accuracy
Leak-proof design
Ease of installation
Chemical compatibility
Surface finish (roughness)
Vibration resistance

Applications Of Stainless Steel Tube Fittings

Stainless steel tube fittings perform across 8 industries where joint integrity, pressure tolerance, and material cleanliness directly affect process safety and output.

Oil and gas industry
Chemical processing industry
Pharmaceutical industry
Power generation plants
Manufacturing industry
Food and beverage industry
Marine engineering and the offshore industry
Aerospace and defense

How To Choose The Right SS Tube Fittings Supplier And Manufacturer?

Selecting the best source for stainless steel tube fittings affects the final cost of procurement, product quality, and delivery reliability. Before placing an order, consider the four important criteria.

Selecting The Right Supplier And Manufacturer

Start with grade and size availability. Ensure that the SS tube fittings manufacturers have the exact alloy and dimensional range as per the project requirements. Also, ensure that the manufacturer and supplier hold the ISO 9001 certification as a minimum baseline. Before finalising any order, request Material Test Reports (MTRs) and dimensional inspection certificates.

Technical Considerations

Choose a fitting type based on temperature, fluid media, and working pressure. For the systems with pressures above 6,000 psi, use compression or flared fittings with smooth, polished surfaces, because standard threaded fittings cannot handle these pressures. Before buying stainless steel tube fittings, make sure their specifications match the tube’s outer diameter (OD) and wall thickness.

Evaluating Supplier Credibility

Before placing an order, review the supplier's export compliance records, customer references, and delivery performance. A trusted stainless steel tube fittings supplier will provide full material traceability reports, dimensional inspection reports, and ASTM, EN, or DIN compliance documents within the required time period.

Procurement Strategy

For repeat orders, use long-term contracts with manufacturers to fix prices and maintain material quality consistently. For one-time projects, confirm minimum order quantity (MOQ), lead time, and packaging needs in advance. Last-minute changes in these areas are a major reason projects get delayed.