IS 780:2016 is the Indian Standard (BIS) for sluice valves for waterworks (cast iron or ductile iron body) - specification. This standard covers the specifications for inside screw, non-rising stem type sluice valves with cast iron or ductile iron bodies used in waterworks. Engineers use this code to define the dimensions, materials, pressure ratings, and hydrostatic testing requirements for valves in municipal and industrial water supply networks.
Specifies requirements for sluice valves of various sizes suitable for waterworks applications.
Key reference values — verify against the current code edition / project specification.
| Reference | Value | Clause |
|---|---|---|
| Scope | CI/DI-body sluice (gate) valves, waterworks, ≤ ~300 mm | Scope |
| Pressure class | PN ≥ main's max (working + surge) | Critical |
| Ends | Flanged/socket matched to pipeline standard/PN | Fit |
| Buried op. | Non-rising spindle, cap-top + tee-key, accessible chamber | Detail |
| Acceptance | Witnessed body hydro test + SEAT leak-tightness test | Critical |
| Larger sizes | > 300 mm → IS 2906 | Cross-ref |
BIM-relevant code. See the BIM Hub for ISO 19650, IFC, and LOD/LOIN frameworks used alongside it.
IS 780:2016 is the specification for sluice valves for waterworks (cast-iron / ductile-iron body) up to ~300 mm — the gate (sluice) valves that isolate sections of water-supply and distribution mains for operation and maintenance. (Larger sizes are covered by IS 2906.) It is the valve spec behind every isolation point in a water network.
It is read with the water-supply stack:
A sluice valve must reliably shut off pressurised water and stay leak-tight for decades in a buried chamber, so IS 780 fixes:
The engineering point: it is buried and forgotten until needed in an emergency burst — so reliability, corrosion protection and *proven seat-tightness* are everything.
Scenario: an isolation sluice valve on a 200 mm DI distribution main.
Step 1 — size & ends: 200 mm, flanged ends drilled to match the IS 8329 DI main's flange standard/PN.
Step 2 — pressure class: select the IS 780 PN class ≥ the main's maximum (working + surge) pressure.
Step 3 — buried-operation detail: non-rising spindle, cap top operated by a tee-key from a surface valve box/chamber; confirm standardised close direction and provide a marker/indicator.
Step 4 — acceptance tests: witness/verify the IS 780 body hydrostatic test and seat leak-tightness test at the rated pressures on the delivered valves — a valve that weeps past the seat is useless for isolation.
Step 5 — install & protect: in an accessible chamber, supported (not hanging on the pipe flanges), with the right coating/wrapping for the soil; thrust/anchorage considered. Record test certificates.
Result: a section of main that can actually be isolated, leak-tight, for the next burst — which is the entire reason the valve exists.
1. Under-rated pressure class / ignoring surge. Sized to working pressure only, the valve leaks or fails under transient (water-hammer) pressure — class to max including surge.
2. No witnessed seat-tightness test. A valve that doesn't shut off bubble-tight cannot isolate the main — the seat test is the critical acceptance, routinely skipped.
3. Flange/end mismatch with the pipeline. Wrong drilling/PN means it won't connect or won't seal at the joints.
4. Wrong operation detail for a buried valve. Specifying a handwheel valve for a buried chamber (vs cap-top + tee-key + surface box) makes it un-operable in service.
5. Inadequate corrosion protection / inaccessible chamber. Buried unprotected valves seize; a valve you can't reach or turn in an emergency is a non-valve.
IS 780:2016 is a current revision and is the working spec for the small/medium isolation valves that make a water network operable — every AMRUT/JJM/township water scheme has thousands of them. They are bought, buried, and ignored until an emergency burst — at which point the *only* thing that matters is whether the valve shuts off bubble-tight and can be turned. That is why the standard's emphasis on the seat-tightness test, pressure class (including surge), buried-operation detail and corrosion protection is the whole point.
The practitioner contract: class the valve to max pressure including surge, match ends/flange to the pipeline, specify the correct buried-operation arrangement (cap-top + tee-key + accessible chamber), witness the body and seat tests on the delivered valves, and protect them for the soil. The expensive operational failure is discovering, during a main burst, that the isolation valve won't seat or won't turn — exactly the failure a properly specified-and-tested IS 780 valve is meant to prevent. Pair with IS 2685 for the selection/installation/maintenance practice.
| Parameter | IS Value | International | Source |
|---|---|---|---|
| Shell Hydrostatic Test Pressure (for PN 1.6 / ~16 bar valve) | 2.4 MPa (1.5 x PN 1.6) | 3.45 MPa (500 psi) for a 250 psi rated valve | AWWA C509-22 |
| Seat Hydrostatic Test Pressure (for PN 1.6 / ~16 bar valve) | 1.76 MPa (1.1 x PN 1.6) | 1.72 MPa (250 psi) for a 250 psi rated valve | AWWA C509-22 |
| Face-to-Face Dimension (DN 300, PN16) | 300 mm (as per IS 14846 / ISO 5752 Series 14) | 457 mm (as per EN 558 Series 15) | BS 5163:2004 |
| Flange Drilling (DN 200, PN16) | 12 holes, 22 mm dia. on a 295 mm PCD | 12 holes, 26 mm dia. on a 295 mm PCD | BS EN 1092-2 (PN16) |
| Epoxy Coating Minimum Thickness (DFT) | 250 microns | 250 microns (as per EN 14901, referenced by BS EN 1074) | BS EN 1074-2:2000 |
| Maximum Operating Torque (DN 200) | 240 N·m (1.2 x DN) | 271 N·m (200 lb·ft) - fixed max for non-geared valves | AWWA C509-22 |
| Body/Bonnet Material | Grey Cast Iron (FG 200/220/260) or Ductile Iron (e.g., SG 400/15) | Ductile Iron (e.g., ASTM A536, Grade 65-45-12) | AWWA C509-22 |