6.1.3

D

A

Sizes and pipe connections

Nominal capacities

For full capacity details for a specific application consult Spirax Sarco.

To accurately size the pump trap, the following data is required.

1. Installation head available, from the base of the pump trap to the

centre line of the heat exchanger / process condensate outlet (m).

If the outlet is mounted vertically, then this should be from the

base of the pump to the face of the outlet.

2. Motive steam pressure available to power the pump trap (bar g).

3. Total backpressure in the condensate return system (bar g).

See note below.

4. Heat exchanger full load operating pressure (bar g).

5. Heat exchanger maximum steam load (kg/h).

6. Minimum temperature of secondary fluid (°C).

7. Maximum controlled temperature of secondary fluid (°C).

Size

Inlet

DN20 x DN20

Fluid connections

Outlet

DN20 (3⁄4")

Motive / Exhaust

DN15 (1⁄2")

BSP

NPT

Body design conditions

Maximum motive inlet pressure

Maximum operating pressure

Maximum backpressure

Maximum operating temperature

Minimum operating temperature

Temperature limits (Ambient

)

Designed for a maximum cold hydraulic test pressure of 15.0 bar g

Minimum installation head (from base of pump)

0.2 m

Recommended minimum installation head (from base of pump) 0.3 m

Safety information, installation and maintenance

For full details see the Installation and Maintenance Instructions

supplied with the product.

Dimensions/weight (approximate) in mm and kg

Size

A

B

C

D

DN20 (3⁄4")

BSP - BS 21 parallel

NPT

Limiting conditions

DN20 x DN20

187

23

223

398

273

220

57

135

171

14

Exhaust

F

H

How to specify

E

I

B

IN

S

E

OUT

C

Condensate pumps

Mechanical pumps and pumps traps

PN10

4.5 bar g

4.5 bar g

4.0 bar g

155°C

-10°C

-10°C to 200°C

Size

Pump discharge/cycle

1.0 metre installation head

At: 4.5 bar g motive pressure

2.5 bar g total backpressure

Note:

DN20 x DN20

2.6 litres

Max. trapping capacity 830 kg/h

Max. pumping capacity 650 kg/h

Page 2 of 4

The pump trap shall be a Spirax Sarco automatic pump trap type APT10-4.5 operated by steam to 4.5 bar g. No electrical energy

shall be required. Body construction from SG iron (GGG 40.3 or ASTM A395) with a swing type inlet check valve and ball type outlet

check valve. The internal trap mechanism shall contain a stainless steel float connected to an internal trap. The pump, trap and check valve

mechanisms shall be incorporated into the same body envelope with no external seals or glands and shall be capable of operating with

a minimum of 200 mm installation head from the base of the unit.

How to order: Example: 1 off Automatic pump trap, type APT10-4.5, DN20 x DN20, complete with motive supply strainer

screwed BSP with BSP motive fluid connections.

APT10-4.5 Automatic Pump Trap

TI-P612-28 ST Issue 4

Page 2 of 4

Total lift or backpressure BP (static head plus pressure head in

the return system) must be below the motive fluid inlet pressure to

allow pump capacity to be achieved.

BP (backpressure) = (H x 0.098 1) + (P) + (Pf)

Height (H) in metres x 0.098 1 plus pressure (P) bar g in the return

line, plus downstream piping friction pressure drop (Pf) in bar.

(Pf can be ignored if the downstream pipework is less than 100 metres

to a non-flooded condensate return and has been sized to take into

account the effect of flash steam at the heat exchanger's full load

operating conditions.)

E

F

G

H

I

Weight

Motive

steam

supply

G