Installation – Flowserve UNA 38 User Manual
Page 12

. Ensure correct position of installation. The name plate
N must always be on top (UNA 38).
. Observe direction of flow. The arrow indicating the flow direction is on the trap body.
3. Consider space required for opening trap. When the trap is installed, a minimum space of at least 
150 mm (UNA 39) or 310 mm (UNA 38) is required for removing the cover
M.
4. Remove plastic plugs. They are
only used as transit protection.
5. Clean the socket-weld ends. 
6. Arc-weld the trap 
only manually (welding process and 4 in accordance with ISO 4063).
Design with socket-weld ends
. Ensure correct position of installation. The name plate
N must always be on top (UNA 38).
. Observe direction of flow. The arrow indicating the flow direction is on the trap body. 
3. Consider space required for opening trap. When the trap is installed, a minimum space of at least 
150 mm (UNA 39) or 310 mm (UNA 38) is required for removing the cover
M.
4. Remove plastic plugs. They are
only used as transit protection.
5. Clean the seating surfaces of both flanges. 
6. Install the steam trap.
Design with flanges
. Ensure correct position of installation. The name plate
N must always be on top (UNA 38).
. Observe direction of flow. The arrow indicating the flow direction is on the trap body.
3. Consider space required for opening trap. When the trap is installed, a minimum space of at least 
150 mm (UNA 39) or 310 mm (UNA 38) is required for removing the cover
M.
4. Remove plastic plugs. They are
only used as transit protection.
5. Clean the butt-weld ends.
6. Arc-weld the trap manually (welding process  and 4 in accordance with ISO 4063) or use 
gas-welding (welding process 3 in accordance with ISO 4063).
Design with butt-weld ends
Installation
Depending on its body design, the float trap UNA 38 can be installed in horizontal or vertical pipes with 
downward flow.
UNA 38
Attention
n
Only qualified welders certified e.g. according to EN 87- may weld the steam trap 
into pressurized lines.
The float trap UNA 39 can be installed in vertical pipes with
downward flow.
UNA 39
