Technical Reference

Material Grades & Technical Charts

One page for the data engineers ask for most — ASTM material specifications, chemical and mechanical properties, equivalent grades, tube pressure ratings, thread data, pressure conversion, soft goods temperature limits and tube fitting installation.

01
Materials

Material Grades & Standards

Standard production is in SS 316 and SS 316L. The grades below are also manufactured to order. Each fitting or valve body is machined from bar stock or forgings to the ASTM specification listed, and tubing / pipe used alongside should be ordered to the matching tube or pipe standard.

Stainless Steel

SS 304 / 304L SS 316 / 316L SS 321 SS 347

Nickel Alloys & Special Grades

Monel 400 Inconel 600 Inconel 625 Hastelloy C-276 Duplex UNS S31803 / S32205 Super Duplex UNS S32750 Alloy 20

Copper Alloys & Carbon Steel

Brass C36000 Brass C37700 (forged) Carbon Steel
MaterialUNS No.Bar StockForgingsSeamless TubePipe
SS 304S30400ASTM A479 / A276ASTM A182 F304ASTM A269 / A213 TP304ASTM A312 TP304
SS 304LS30403ASTM A479 / A276ASTM A182 F304LASTM A269 / A213 TP304LASTM A312 TP304L
SS 316S31600ASTM A479 / A276ASTM A182 F316ASTM A269 / A213 TP316ASTM A312 TP316
SS 316LS31603ASTM A479 / A276ASTM A182 F316LASTM A269 / A213 TP316LASTM A312 TP316L
SS 321S32100ASTM A479 / A276ASTM A182 F321ASTM A269 / A213 TP321ASTM A312 TP321
Monel 400N04400ASTM B164ASTM B564ASTM B165ASTM B165
Inconel 600N06600ASTM B166ASTM B564ASTM B167ASTM B167
Inconel 625N06625ASTM B446ASTM B564ASTM B444ASTM B444
Hastelloy C-276N10276ASTM B574ASTM B564ASTM B622ASTM B622
Duplex 2205S31803 / S32205ASTM A479ASTM A182 F51 / F60ASTM A789ASTM A790
BrassC36000 / C37700ASTM B16ASTM B283ASTM B135—
For reference only. The specification applied to your order is stated on the quotation and on the EN 10204 3.1 material certificate.
02
Material Charts

Chemical Composition

GradeCMnSiPSCrNiMoOthers
SS 3040.082.001.000.0450.03018.0–20.08.0–10.5—N 0.10
SS 3160.082.001.000.0450.03016.0–18.010.0–14.02.0–3.0N 0.10
SS 316L0.0302.001.000.0450.03016.0–18.010.0–14.02.0–3.0N 0.10
Monel 4000.302.000.50—0.024—63.0 min—Cu 28.0–34.0, Fe 2.5
Inconel 6000.151.000.50—0.01514.0–17.072.0 min—Fe 6.0–10.0, Cu 0.50
Inconel 6250.100.500.500.0150.01520.0–23.058.0 min8.0–10.0Nb+Ta 3.15–4.15, Fe 5.0
Hastelloy C-2760.0101.000.080.040.0314.5–16.5Balance15.0–17.0W 3.0–4.5, Fe 4.0–7.0
Duplex 22050.0302.001.000.0300.02022.0–23.04.5–6.53.0–3.5N 0.14–0.20
Brass C36000————————Cu 60.0–63.0, Pb 2.5–3.7, Fe 0.35, Zn Bal.
For reference only. Values in weight %. Single values are maximum unless stated. Limits as per the applicable ASTM bar stock specification.
03
Material Charts

Mechanical Properties

GradeTensile Strength (MPa, min)Yield Strength 0.2% (MPa, min)Elongation (%, min)Hardness (max)
SS 30451520540201 HB
SS 31651520540217 HB
SS 316L48517040217 HB
Monel 40048017035—
Inconel 60055024030—
Inconel 62582741430—
Hastelloy C-27669028340—
Duplex 220565545025290 HB
Brass C36000338–469*124–310*18–53*—
For reference only. Annealed condition. *Brass values are typical ranges depending on temper and bar diameter.
04
Material Charts

Physical Properties

GradeDensity (g/cm³)Melting Range (°C)Key Characteristic
SS 3048.001400–1450General corrosion resistance, economical
SS 316 / 316L8.001375–1400Molybdenum for chloride & pitting resistance
Monel 4008.801300–1350Sea water, hydrofluoric acid service
Inconel 6008.471354–1413High temperature oxidation resistance
Inconel 6258.441290–1350High strength, crevice corrosion resistance
Hastelloy C-2768.891325–1370Severe oxidising & reducing chemicals
Duplex 22057.801385–1445High strength, stress corrosion cracking resistance
Brass C360008.50885–900Free machining, water & air service
For reference only. Typical values; they are not guaranteed minimums.
05
Cross Reference

Equivalent Grades

ASTM / AISIUNSWerkstoff Nr.ENJIS
304S304001.4301X5CrNi18-10SUS304
304LS304031.4307X2CrNi18-9SUS304L
316S316001.4401X5CrNiMo17-12-2SUS316
316LS316031.4404X2CrNiMo17-12-2SUS316L
321S321001.4541X6CrNiTi18-10SUS321
Duplex 2205S322051.4462X2CrNiMoN22-5-3—
Monel 400N044002.4360NiCu30Fe—
Inconel 600N066002.4816NiCr15Fe—
Inconel 625N066252.4856NiCr22Mo9Nb—
Hastelloy C-276N102762.4819NiMo16Cr15W—
For reference only. Equivalents are close but not always identical in composition limits — confirm against the governing standard where it matters for your application.
06
Tubing

Tube Pressure Ratings & Sizes

SS 316 Seamless Tubing (ASTM A269)

Tube OD0.028" wall0.035" wall0.049" wall0.065" wall0.083" wall0.109" wall
1/8"850010900————
1/4"40005100750010200——
3/8"—330048006500——
1/2"—2600370051006700—
3/4"——240033004200—
1"———240031004200
Pressures in PSIG at ambient temperature, for reference only. The rating of a tube system is set by the tubing, not the fitting. Compression tube fittings are rated up to 6000 PSI depending on size, material and tube wall thickness.

Fractional Tube — OD, Wall & Inside Diameter

Tube ODOD (mm)Wall (in)Wall (mm)ID (in)ID (mm)
1/8"3.180.0280.710.0691.75
1/8"3.180.0350.890.0551.40
1/4"6.350.0350.890.1804.57
1/4"6.350.0491.240.1523.86
1/4"6.350.0651.650.1203.05
3/8"9.530.0350.890.3057.75
3/8"9.530.0491.240.2777.04
3/8"9.530.0651.650.2456.22
1/2"12.700.0491.240.40210.21
1/2"12.700.0651.650.3709.40
1/2"12.700.0832.110.3348.48
3/4"19.050.0651.650.62015.75
3/4"19.050.0832.110.58414.83
1"25.400.0832.110.83421.18
1"25.400.1092.770.78219.86

Metric Tube — Common OD × Wall

Tube OD (mm)Wall (mm)ID (mm)
61.04.0
81.06.0
101.08.0
121.010.0
121.59.0
161.513.0
202.016.0
252.520.0
For reference only. ID = OD − 2 × wall, nominal values before tolerances. Use fully annealed seamless or welded & drawn tubing, hardness HRB 80 max (ASTM A269 / A213).
07
Threads

NPT, BSPT & BSPP Thread Data

FeatureNPTBSPT (R / Rc)BSPP (G)
Full NameNational Pipe TaperBritish Standard Pipe TaperBritish Standard Pipe Parallel
StandardASME B1.20.1ISO 7 (BS EN 10226)ISO 228
Thread Angle60°55°55°
Taper1:16 on diameter1:16 on diameterParallel (no taper)
Crest / RootFlatRoundedRounded
Sealing MethodOn the threads — interference fit with PTFE tape or thread sealantOn the threads — interference fit with PTFE tape or thread sealantNot on the threads — bonded washer, O-ring or gasket against a face
Common UseNorth American & oil and gas specificationsEurope, Asia & Indian process plantsGauge connections, hydraulic ports with face seals
For reference only. NPT and BSP threads look similar but are not interchangeable — the thread angle and pitch differ in most sizes, and a mixed joint will leak.
Nominal SizeNPT (TPI)NPT Pitch (mm)BSPT / BSPP (TPI)BSP Pitch (mm)
1/8"270.941280.907
1/4"181.411191.337
3/8"181.411191.337
1/2"141.814141.814
3/4"141.814141.814
1"11.52.209112.309
For reference only. 1/2" and 3/4" share 14 TPI in both systems, but the 60° and 55° thread forms still do not seal against each other.
08
Conversion

Pressure Unit Conversion

1 Unit ofbarpsikPaMPakg/cm²
1 bar114.5041000.11.0197
1 psi0.0689516.8950.0068950.07031
1 kPa0.010.1450410.0010.010197
1 MPa10145.041000110.197
1 kg/cm²0.9806714.22398.0670.0980671
1 atm1.0132514.696101.3250.1013251.0332
For reference only. Read across: 1 unit in the left column equals the value shown under each unit.
psibarMPakg/cm²
100068.96.8970.3
2000137.913.79140.6
3000206.820.68210.9
5000344.734.47351.5
6000413.741.37421.8
10000689.568.95703.1
For reference only. Rounded values for the common valve and fitting pressure classes.
ASME ClassApprox. PN Equivalent
150#PN 20
300#PN 50
600#PN 100
900#PN 150
1500#PN 250
2500#PN 420
For reference only. ASME class and PN ratings are approximate equivalents — actual allowable pressure depends on material group and temperature per ASME B16.5 / EN 1092-1. Flange dimensions are not interchangeable between the two systems.
09
Soft Goods

Seat, Packing & Seal Temperature Limits

MaterialTypical Range (°C)Used ForNotes
PTFE-54 to 232Ball valve seats, stem packingChemically inert; pressure rating falls as temperature rises
RPTFE (glass filled)-54 to 232Ball valve seatsBetter creep and wear resistance than virgin PTFE
PEEK-54 to 260High pressure seats, stem tipsHigh strength at elevated temperature and pressure
Grafoil (flexible graphite)-200 to 450Needle valve & manifold packingFire safe, high temperature steam service
Viton (FKM)-20 to 204O-rings, soft sealsGood for hydrocarbons and many acids
Buna-N (NBR)-30 to 121O-rings, soft sealsOils, fuels, water and air
EPDM-45 to 150O-rings, soft sealsHot water and steam; not suitable for oils
For reference only. Typical ranges — the working limit of a valve is the lower of the body, seat and packing ratings at the given pressure. Check the product datasheet for the rating of a specific part.
10
Installation

Tube Fitting Installation Steps

Cut the Tube Square

Use a tube cutter or a fine-tooth hacksaw with a guide so the end is square to the tube axis.

Deburr & Clean

Remove inside and outside burrs and clean off chips so nothing enters the system or scores the ferrule seat.

Insert Fully

Push the tube into the fitting until it bottoms firmly on the body shoulder.

Finger Tight

Run the nut down finger tight while keeping the tube bottomed.

Mark the Nut

Mark the nut at the 6 o'clock position so the tightening turns can be counted.

Tighten 1-1/4 Turns

Hold the body with a spanner and turn the nut 1-1/4 turns. For 1/8" / 3 mm and smaller, tighten 3/4 turn only.

Gap Gauge Check

Where a gap inspection gauge is available, confirm it does not enter between nut and body.

For reference only. For remakes, insert the tube with pre-swaged ferrules, tighten finger tight, then snug slightly with a spanner. Do not mix nuts, ferrules and bodies from different manufacturers on one joint.

Need a Datasheet or Drawing?

Share the part number, size and material — our technical team will send the pressure rating chart, drawing and material certificate details.