Hex Head Seal Bolts with Under Head Seal

Hex Head Seal Bolts with Under Head Seal are widely used as a gasket alternative due to their excellent resistance to a range of chemicals and automotive fluids such as alcohol, gasoline, kerosene, oil, diesel fuel and hydraulic fluids.

This all-in-one sealing solution features a highly durable green seal that is permanently fused to the bearing surface of the screw. When fastened, the element is compressed to create a gasket-type seal between the bearing surface and mating surface, preventing the leakage of fluids and gases under pressure.

Hex Head Seal Bolts with Under Head Seal also prevent galvanic corrosion between dissimilar materials and provide a cost-effective alternative to standard o-ring seal bolts – supplied with a much shorter lead time.

Hex Head Seal Bolts with Under Head Seal and Slotted Hex Head Seal Bolts with Under Head Seal are available at Fastenright. Both components can be supplied as a partially threaded bolt, typically to DIN 931 / ISO 4014 /  ASME B18.2.1, or as a fully threaded set screw, typically to DIN 933 / DIN 933SZ / ISO 4017 / ASME B18.6.3.

The seal can be applied to all of our standard materials, including Steel and Stainless Steel, with non-standard materials and finishes available on request. Special seal colours can also be supplied.

Non-standard sizes, materials and finishes are available to order as specials, including small volume manufacture, modifications and bespoke parts made to drawings. Minimum order quantities apply.

We supply an extensive range of Sealing Fasteners here at Fastenright.

M20 to M52

3mm

4mm

5mm

6mm

8mm

10mm

12mm

14mm

16mm

18mm

20mm

22mm

25mm

30mm

35mm

40mm

45mm

50mm

55mm

60mm

65mm

70mm

75mm

80mm

85mm

90mm

95mm

100mm

110mm

120mm

130mm

140mm

150mm

160mm

*

*

170mm

*

*

180mm

*

*

190mm

*

*

200mm

*

*

210mm

*

*

*

*

220mm

*

*

*

*

230mm

*

*

*

*

240mm

*

*

*

*

250mm

*

*

*

*

260mm

*

*

*

*

270mm

*

*

*

*

280mm

*

*

*

*

290mm

*

*

*

*

300mm

*

*

*

*

320mm

*

*

*

340mm

*

*

*

360mm

*

*

*

380mm

*

*

*

400mm

*

*

*

420mm

*

*

*

440mm

*

*

*

460mm

*

*

*

480mm

*

*

*

500mm

*

*

*

520mm

*

*

*

540mm

*

*

*

560mm

*

*

*

580mm

*

*

*

600mm

*

*

*

= A2 / 304 Stainless Steel //  = A4 / 316 Stainless Steel Parts with * are available for DIN 931 only. Size not listed? Please contact us – we may be able to provide it.

ASME B18.2.1 1/4″ to 1/2″

20mm

22mm

25mm

30mm

35mm

40mm

45mm

50mm

55mm

60mm

65mm

70mm

75mm

80mm

85mm

90mm

95mm

100mm

*

*

110mm

*

*

*

120mm

*

*

*

*

130mm

*

*

*

*

*

140mm

*

*

*

*

*

150mm

*

*

*

*

*

160mm

*

*

*

*

*

*

170mm

*

*

*

*

*

*

180mm

*

*

*

*

*

*

190mm

*

*

*

*

*

*

200mm

*

*

*

*

*

*

210mm

*

*

*

*

*

*

*

*

*

*

*

220mm

*

*

*

*

*

*

*

*

*

*

*

230mm

*

*

*

*

*

*

*

*

*

*

*

240mm

*

*

*

*

*

*

*

*

*

*

*

250mm

*

*

*

*

*

*

*

*

*

*

*

260mm

*

*

*

*

*

*

*

*

*

270mm

*

*

*

*

*

*

*

*

*

280mm

*

*

*

*

*

*

*

*

*

290mm

*

*

*

*

*

*

*

*

*

300mm

*

*

*

*

*

*

*

*

*

320mm

*

*

340mm

*

*

360mm

*

*

380mm

*

*

400mm

*

*

420mm

*

*

440mm

*

*

460mm

*

*

480mm

*

*

500mm

*

*

520mm

*

*

540mm

*

*

560mm

*

*

580mm

*

*

600mm

*

*

= A2 / 304 Stainless Steel // = A4 / 316 Stainless Steel Parts with * are available for DIN 931 only. Size not listed? Please contact us – we may be able to provide it.

ASME B18.2.1 9/16″ to 1″

1 1/4″
1 3/8″
1 1/2″
1 5/8″
1 3/4″
2″
2 1/4″
2 1/2″
2 3/4″
3″
3 1/4″
3 1/2″
3 3/4″
4″
4 1/2″
5″
5 1/2″
6″
7″
8″
9″
10″
11″
12″
14″
16″
18″
20″

= A2 / 304 Stainless Steel // = A4 / 316 Stainless Steel Size not listed? Please contact us – we may be able to provide it.

ASME B18.6.3 No.4 to 7/16″

2″
2 1/4″
2 1/2″
2 3/4″
3″
3 1/4″
3 1/2″
3 3/4″
4″
4 1/2″
5″
5 1/2″
6″
7″
8″
9″
10″
11″
12″
14″
16″
18″
20″

= A2 / 304 Stainless Steel // = A4 / 316 Stainless Steel Size not listed? Please contact us – we may be able to provide it.

ASME B18.6.3 7/16″ to 1″

1/4″

5/16″

3/8″

7/16″

1/2″

9/16″

5/8″

3/4″

7/8″

1″

1 1/4″

1 1/2″

1 3/4″

2″

2 1/4″

2 1/2″

2 3/4″

3″

3 1/4″

3 1/2″

3 3/4″

4″

4 1/2″

5″

5 1/2″

6″

7″

8″

9″