Description

DCV8 disc check valves are of a wafer pattern, designed to be sandwiched between DIN 2501 and EN 1092 flanges. Their function is to prevent reverse flow on a wide variety of fluids.

• Aggressive Fluids: Suitable for use with aggressive fluids, vapours, acids, and alkalines at high pressures and temperatures.
• Earthing: The valves are provided with an M8 threaded tapping for product earthing.
• Spring Options: Available with standard, heavy duty (boiler feed), or high temperature (Nimonic 90) springs.
• Soft Seats: Optional Viton or EPDM soft seats for zero leakage in gas or water applications.

Standards & Certification

• This product fully complies with the requirements of the EU Pressure Equipment Directive 2014/68/EU.
• Designed and manufactured in accordance with AD Merkblatter.
• Standard metal shut-off conforms to EN 12266-1 Rate D.
• Soft seated versions meet EN 12266-1 Rate A (providing a differential pressure exists).
• Certification to EN 10204 3.1 is available.

Sizes and Pipe Connections

• Sizes: DN15, DN20, DN25, DN32, DN40, DN50, DN65, DN80, and DN100.
• Connections: Suitable for installation between EN 1092 / DIN 2501 PN10, PN16, PN25 and PN40 flanges.
  • Note: DN100 will not fit between PN16 and PN25 flanges.

Materials

No.	Part	Material	Standard
1	Body	Austenitic stainless steel	WS 1.4408
2	Disc	Austenitic stainless steel	ASTM A276 316 / WS 1.4401
3	Spring retainer	Austenitic stainless steel	BS 1449 316 S11 / WS 1.4435
4	Standard spring	Austenitic stainless steel	BS 2056 316 S42 / WS 1.4401
4	Heavy duty spring	Austenitic stainless steel	BS 2056 316 S42
4	High temp spring	Nickel alloy	Nimonic 90

Pressure / Temperature Limits

Operating Range:

• A - B - D: Without standard or high temperature springs.
• E - C - D: Standard spring and heavy duty spring.

Condition	Value
PMA Max allowable pressure	40 bar g @ 50 °C
TMA Max allowable temperature	400 °C @ 25.6 bar g
Minimum allowable temperature	-196 °C
PMO Max operating pressure (Standard spring)	40 bar g @ 50 °C
TMO Max operating temperature (Standard spring)	300 °C @ 27.6 bar g
TMO Max operating temperature (Heavy duty spring)	300 °C @ 27.6 bar g
TMO Max operating temperature (High temp spring)	400 °C @ 25.6 bar g
TMO Max operating temperature (Without spring)	400 °C @ 25.6 bar g
Viton seat Temperature limits	-25 °C to +205 °C
EPDM seat Temperature limits	-40 °C to +120 °C
Cold hydraulic test pressure	60 bar g

Dimensions and Weights

(approximate) in mm

Size	A*	B	C	D	E	Weight (kg)
DN15	16.0	53	15	65	23.0	0.18
DN20	19.0	63	20	72	28.0	0.27
DN25	22.0	72	25	78	33.8	0.40
DN32	28.0	84	32	93	41.8	0.67
DN40	31.5	94	40	104	49.8	0.90
DN50	40.0	109	50	115	59.8	1.45
DN65	46.0	129	65	138	75.8	2.14
DN80	50.0	144	80	152	90.8	2.69
DN100 (PN16)	60.0	164	100	171	111.8	4.36
DN100 (PN40)	60.0	169	100	174	111.8	4.36

*A conforms to EN 558 part 1, series 49.

Opening Pressures (mbar)

Differential pressures with zero flow:

Flow	DN15	DN20	DN25	DN32	DN40	DN50	DN65	DN80	DN100
↑	25	25	25	27	28	29	30	31	33
→	22.5	22.5	22.5	23.5	24.5	24.5	25	25.5	26.5
↓	20	20	20	20	20	20	20	20	20

• Without spring (vertical ↑): approx 2.5 to 6.5 mbar.
• Heavy duty spring: approx 700 mbar.

Pressure Loss Diagram

The pressure loss diagram is for valves open at 20 °C. The values indicated are applicable to spring loaded valves with horizontal flow. With vertical flow, insignificant deviations occur only within the range of partial opening.

The curves given in the chart are valid for water at 20 °C. To determine the pressure for other fluids the equivalent water volume flowrate must be calculated and used in the graph:

Vw = √(ρ / 1000) × V

Where:

• Vw = Equivalent water volume flow in l/s or m³/h
• ρ = Density of fluid in kg/m³
• V = Volume of fluid in l/s or m³/h

Pressure loss information for steam, compressed air and gases is available from Spirax Sarco.

Kv Values

DN	15	20	25	32	40	50	65	80	100
Kv	4.4	6.8	10.8	17	26	43	60	80	113

Installation and Maintenance

• Direction: Fitted in accordance with the direction of flow arrow.
• Position: Valves with springs can be installed in any plane. Valves without springs must be fitted in a vertical flow line with flow from bottom-to-top.
• Limitations: Disc check valves are not suitable for use where heavily pulsating flow exists (e.g., close to a compressor).
• Maintenance: DCV8 disc check valves are non-maintainable (no spares are available).
• Safety: If Viton components are subjected to temperatures above 315 °C, they may decompose and form hydrofluoric acid.

How to Order

Example: 1 off Spirax Sarco DN25, DCV8 disc check valve for fitting between DIN 2501/EN 1092 DN25 PN40 flanges.