Wing Nut Test Plugs

Wing nut test plugs mechanically expand a rubber seal against the pipe bore for low-pressure blocking or bypass applications. The listed sizes are nominal 2–12 in (DN 50–300), with a separate pressure limit for each size. Select from actual bore measurements and the required test conditions.

Mechanical pipe sealing with a bypass connection

Turning the wing nut compresses and expands the rubber sealing ring against the pipe interior. The ported stem provides a connection for an appropriate fill, drain or bypass arrangement. Match the plug to the actual bore and installation conditions; nominal pipe size alone is not sufficient.

Size-specific specification table

The seven-size chart below follows the Iron Grip specifications used for this listing. Pressure and water-head values are alternative expressions of each model’s limit, not additive allowances.

Nominal size (in / DN)	Usage bore (in)	Maximum back pressure (psi)	Water head (ft)	Length (in)	Weight (lb)	NPT bypass
2 / DN 50	1.94–2.12	13	30	9.75	1.1	3/8 in male
3 / DN 75	2.82–3.12	11	25	12.75	2.3	1/2 in male
4 / DN 100	3.6–4.06	8.7	20	12.75	3.1	1/2 in male
6 / DN 150	5.57–6.12	4.3	10	12.75	5.6	1/2 in male
8 / DN 200	7.72–8.2	4.3	10	17	11.5	1/2 in male
10 / DN 250	9.8–10.2	3.5	8	17	20	1/2 in male
12 / DN 300	11.56–12.2	2.6	6	19.5	28	1 in male

For metric conversion, 1 inch = 25.4 mm and 1 lb ≈ 0.4536 kg. For example, the 3-inch model’s 2.82–3.12-inch bore range is approximately 71.6–79.2 mm; the 8-inch model’s 11.5-lb weight is approximately 5.2 kg. Use the actual bore range rather than treating a DN designation as a measured diameter.

Confirm the application and installation

Provide the pipe material, measured ID, condition of the sealing surface, test medium, maximum pressure or liquid head, temperature and required bypass connection. A rating for one size does not apply to the others. Justram can check the supplied plug identity and suitability against these requirements.

Use the manufacturer’s installation and blocking instructions, including required restraint for air testing. Release pressure before adjusting or removing the plug. Tightening methods and any tool use must follow the supplied model’s instructions.