ASTM F2437

ASTM F2437 – Compressible Washer Type Direct Tension Indicators

ASTM F2437 specifies the standards for compressible washer-type direct tension indicators designed for use with bolts, cap screws, studs, and anchors. Manufactured in diameters from 1/4 inch up to 2-1/2 inches, these washers help ensure accurate and consistent bolt tensioning during installation. The standard includes two styles of washers, with two performance grades available under each style, offering flexibility to meet different application and strength requirements.

ASTM F2437 Direct Tension Indicator (DTI) – Bolt, Nut & Washer Compatibility Chart :

Indicator Style / Grade	Compatible Bolts, Cap Screws, Studs, or Anchors	Matching Hex or Heavy Hex Nut	Recommended Washer
Style 2 – Grade 55	ASTM F1554 Gr.55 or ASTM A307	ASTM A194 2H / ASTM A563 Gr.A, C, or DH	ASTM F436
Style 2 – Grade 105	ASTM A193 B7 or ASTM F1554 Gr.105	ASTM A194 2H / ASTM A563 DH	ASTM F436
Style 1 – Grade 5	ASTM A449 / ASTM A354 Gr.BC or SAE J429 Gr.5	ASTM A563 Gr.B, C, D, DH or SAE J995 Gr.5	ASTM F436
Style 1 – Grade 8	ASTM A354 BD or SAE J429 Gr.8	ASTM A563 Gr.D, DH or SAE J995 Gr.8	ASTM F436

ASTM F2437 Compression Load Range by Bolt Diameter and Grade :

Compression Load Capacity Range (lbs)
Nominal Diameter (in.)	Grade 5	Grade 8	Grade 55	Grade 105
1/2"	9,700 – 10,700	13,700 – 15,340	4,450 – 4,900	8,500 – 9,400
5/8"	15,550 – 17,200	21,850 – 24,200	7,050 – 7,800	13,500 – 15,000
3/4"	22,600 – 25,000	31,900 – 35,300	10,500 – 11,600	20,000 – 22,150
7/8"	30,850 – 34,100	43,550 – 48,100	14,500 – 16,000	27,650 – 30,550
1"	40,200 – 44,400	56,700 – 62,700	19,000 – 21,000	36,250 – 40,100
1-1/8"	40,250 – 44,450	73,150 – 80,900	23,950 – 26,450	47,300 – 52,300
1-1/4"	51,100 – 56,450	91,750 – 101,450	30,400 – 33,600	59,850 – 66,150
1-3/8"	61,150 – 67,600	112,450 – 124,250	38,550 – 42,600	73,800 – 81,600
1-1/2"	74,350 – 82,150	135,150 – 149,400	44,050 – 48,700	89,300 – 98,700
1-3/4"	74,450 – 82,300	177,850 – 196,500	59,550 – 65,850	124,600 – 137,750
2"	98,000 – 108,300	236,850 – 261,750	78,650 – 86,950	165,800 – 183,300
2-1/4"	127,400 – 140,800	277,900 – 307,100	102,050 – 112,750	212,900 – 235,350
2-1/2"	156,750 – 173,250	379,600 – 419,600	125,400 – 138,600	240,550 – 265,850

Typical Chemical Composition Range
Element	Permissible Range (%)
Carbon (C)	0.30 – 0.55%
Manganese (Mn)	0.50 – 0.90%
Silicon (Si)	0.15 – 0.35%
Phosphorus (P)	0.040% max
Sulfur (S)	0.045% max