The TUPY Brazil lock nut (figure 312) is run onto a pipe thread to lock a component in a set position, or to stop a joint working loose under vibration.
| Figure number | 312 |
| Size range | 3/8in to 3in |
| Finish | Galvanised and black |
| Thread | BSP |
| Standard | ISO/EN/NBR P4 |
| Maximum working pressure | 25 bar |
| Material | Malleable cast iron |
TUPY Brazil fittings are manufactured and inspected under the supervision of the international bodies above, and carry recognised approvals for use in fire protection, water and gas networks.
The dimension letters follow the technical drawing above. Weights are per single fitting, in kilograms.
| Nominal diameter | Dimensions (mm) | Weight (kg) | |||
|---|---|---|---|---|---|
| inch | mm | a | s | Galvanised | Black |
| 3/8" | 10 | 8 | 27 | 0.023 | 0.021 |
| 1/2" | 15 | 9 | 32 | 0.031 | 0.029 |
| 3/4" | 20 | 10 | 36 | 0.036 | 0.035 |
| 1" | 25 | 11 | 46 | 0.065 | 0.062 |
| 1.1/4" | 32 | 12 | 55 | 0.099 | 0.094 |
| 1.1/2" | 40 | 13 | 60 | 0.110 | 0.104 |
| 2" | 50 | 14 | 75 | 0.174 | 0.165 |
| 2.1/2" | 65 | 17 | 95 | 0.355 | 0.348 |
| 3" | 80 | 20 | 105 | 0.413 | 0.399 |
Source: the official TUPY Brazil BSP threaded fittings catalogue.
Need pricing for this fitting?
Send us the figures and sizes you need and our Dubai office will come back with a quotation, stock position and lead time.
When a component has to stay at a particular angle or height on a thread — where a pipe passes through a wall, when fixing a valve, or when mounting a flange — screwing the thread fully home will not hold it where you want it. The lock nut bears against the component from behind and locks it in place.
Its second use is to hold a joint against gradually working loose on lines that vibrate.
The thread on this figure is to ABNT NBR 8133 and ISO 228. Sizes run from 3/8 to 3in.
Sample dimensions: ⅜in code 1206003, thickness a = 8 and across flats s = 27 mm; ½in code 1206004, a = 9, s = 32; 1in code 1206007, a = 11, s = 46; 2in code 1206010, a = 14, s = 75; and 3in code 1206012, a = 20, s = 105 mm. Galvanised weight runs from 0.023 to 0.413 kg.
The material is blackheart malleable cast iron to grade JMB 350-10, finished hot-dip galvanised or black.
The TUPY Brazil Lock Nut is made in 9 sizes, from 3/8" to 3". The full list of sizes, with the dimensions in millimetres and the weight of each piece, is in the dimensions and weights table on this page.
The weight depends on the size: the 1" size, for example, weighs 0.065 kg galvanised and 0.062 kg black. The weights of every size are taken from the official TUPY catalogue and are listed in the table on this page, so they can be used to work out shipping weight and freight cost.
TUPYBSP fittings are threaded to BSP in accordance with ISO 7-1; the male thread is tapered and the seal is made on the thread itself. BSP is not interchangeable with NPT, and screwing the two together will leak. TUPY also produces a separate NPT line, which is covered in the downloads section.
According to TUPY's technical catalogue, the working pressure of TUPYBSP fittings is 25 bar between −20 °C and +120 °C. It falls to 20 bar above 300 °C, and intermediate values are interpolated. The design pressure in the hydrostatic test is 100 bar for sizes up to 4 in and 64 bar for 5 in and 6 in.
The TUPY Lock Nut is manufactured to ISO/EN/NBR P4. TUPY malleable cast iron fittings are built to ISO 49, EN 10242 and ABNT NBR 6943, and their threads follow ISO 7-1. The factory certificates can be seen in the standards and certifications section on this page.
On the body of every genuine TUPY fitting the factory mark, the figure number and the size are raised in the casting, not etched or printed. The threads are clean and free of burrs, and the galvanised coating is even. The surest check is to weigh the piece and compare it with the weight table on this page; counterfeit pieces usually come out lighter than the official catalogue weight.
Use the request a quote page at /request-a-quote and tell us the figure number (312), the sizes and the quantities you need. Our Dubai office will come back with a quotation, the current stock position and a lead time. Amini Building Materials Trading L.L.C is the exclusive agent of TUPY S.A. in the Middle East and supplies the region from Dubai.
