0091-22-66157017

info@torqbolt.com

Home

ASTM A453 Grade 660 Class A Specification

ASTM A453 Grade 660 Class A Specification provides a yield strength viz. 85 ksi [585 MPa] respectively for use in high temperature service for bolting components such as Stud bolts, screws, nuts, hex bolts & various other fasteners for pressure vessel and valve flanges. A453 Grade 660 Class A is equivalent to class D when manufactured in single age hardened condition. A453 Grade 660 Cl A Studs and nuts are capable of meeting impact test requirements of 40 joules minimum at - 196 Degrees Centigrade. ASTM A453 Grade 660 Class A is produced in various other forms like wire rods, round bars, shafts, castings, forgings, threaded bars, threaded rods, wires, tubings, sheets, plates, welding rods, hex bars, Rivets & Springs. Class A is stress rupture tested for 100 Hours at 650°C in finished condition. Class A Bolting can be certified under nace provided the hardness is controlled and not over 35HRC.

Properties
Chemical Composition
Mechanical Properties
Stress Rupture Test
Heat Treatment
Annealing & Ageing Cycles
Continuous Heat Treatment Charge Sizes
Lot / Batch Sizes
Marking Requirements
Bolting Threading Types
Product Range

ASTM A453 Grade 660 Class A Properties

Chemical Composition

Grade	ASTM A453 Grade 660 Class A
UNS Number	S66286
Elements	Content, %	Product Analysis Variation, Over or Under, %
Carbon (C)	0.08 max	0.01 over
Manganese (Mn)	2.00 max	0.04
Phosphorus (P)	0.040 max	0.005 over
Sulfur (S)	0.030 max	0.005 over
Silicon (Si)	1.00 max	0.05
Nickel (Ni)	24.0-27.0	0.2
Chromium (Cr)	13.5-16.0	0.2
Molybdenum (Mo)	1.00-1.50	0.05
Titanium (Ti)	1.90-2.35	0.05
Aluminum (Al)	0.35 max	0.05 over
Vanadium (V)	0.10-0.50	0.03
Boron (B)	0.001-0.010	0.0004 under to 0.001 over

Mechanical Properties

Grade		ASTM A453/A453M Grade 660
Class		A
Tensile Strength, min	ksi	130
Tensile Strength, min	MPa	895
Yield Strength (0.2 % Offset), min	ksi	85
Yield Strength (0.2 % Offset), min	MPa	585
Elongation in 4× Diam, min, %		15
Reduction of Area, min, %		18
Brinell Hardness Number		248-341
Approximate Rockwell Hardness, B and C	min	24 HRC
Approximate Rockwell Hardness, B and C	max	37 HRC

Stress Rupture Test

ASTM A453 Grade 660 Class A Stress Rupture

Grade	Class	Test Temperature, °F [°C]	Stress, min		Time to Rupture, min, h^A	Elongation, min, %
Grade	Class	Test Temperature, °F [°C]	ksi	MPa	Time to Rupture, min, h^A	Elongation, min, %
ASTM A453/A453M Grade 660	A	1200 [650]	56	385	100	5
(A) The combination bar specimen shown in Fig. 1 shall be tested continuously at the temperature and at the minimum stress specified or at a greater stress and shall rupture in a time not less than that specified. (A) When it is necessary to heat treat or heat treat and pickle after cold finishing, because of special hardness or mechanical property requirements, the permissible variations are generally double those shown in the table. (B) For size tolerances of sizes over 4 in. [100 mm], the manufacturer should be consulted.

Heat Treatment

Annealing & Ageing Cycles

Grade Symbol	Class	Solution Treatment	Hardening Treatment
ASTM A453/A453M Grade 660	A	1650 ± 25 °F [900 ± 14 °C], hold 2 h, min, and liquid quench	1325 ± 25 °F [720 ± 14 °C], hold 16 h, air cool
(A) Times refer to the minimum time material is required to be at temperature.

Continuous Heat Treatment Charge Sizes

Diameter, in. [mm]	Weight, lb [kg]
To 1³/₄ [44]	3000 [1400]
Over 1³/₄ [44] to 2¹/₂ [63]	6000 [2700]
Over 2¹/₂ [63]	12000 [5400]

Lot / Batch Sizes

Diameter, in. [mm]	Maximum Lot Size, lb [kg]
1¹/₂ [38] and under	200 [90]
Over 1¹/₂ [38] to 1³/₄ [44], incl	300 [140]
Over 1³/₄ [44] to 2¹/₂ [63], incl	600 [270]
Over 2¹/₂ [63]	20 pieces

Marking Requirements

Grade	Marking
ASTM A453/A453M GRADE 660 CLASS A	TB 660A M1/M2/R1/R2

Bolting Threading Types

Specification	Grade	UNS No.	CLASS	Type
ASTM A453/A453M	Grade 660	S66286	Class A	M1	M2	R1	R2

ASTM A453 Grade 660 Class A Product Range

Based on the application & Usage

A453 gr.660 cl.a

ASTM A453 gr. 660 cl a

A453 grade 660 class a

ASTM A453 grade 660 class a

SA 453 gr 660 class a

SA 453-660a

SA-453-660 a

A453 660a

A453 gr 660 a

A453 gr 660 bolts

A453 gr 660 class a

A453 gr 660a bolts

ASTM A453 660a

A453 grade 660 bolts

ASTM A453 gr. 660 cl.a

ASTM A453 grade 660 a

ASTM A453 grade 660 bolts

SA 453 660 a

SA 453 gr 660 a

SA 453 grade 660 class a

SA 453-660 a

SA 453-660 type a

Specifications

ASTM A453
ASTM A638
EN 10269
EN 10083-3
ISO 3506-5
DIN 267

Surface Treatments

Xylan 1070 / 1014 / 1400 / 1424
Xylar 2 / 101
SermaGard 1105 / 1280
Dacromet 320 / 500
TakeCoat 1000 Ceramic
Magnigard
MolyKote

Certifications

ISO 9001 - 2015 Certified
PED 2014/68/EC
NACE MR0175/ISO 15156-2
NORSOK M-650
DFAR
MERKBLATT AD 2000 W2/W7/W10

About Us

Questions? Contact us.

Showcase of our Microsites.

ASTM A453 Grade 660 Class A Specification

Table Of Contents