Liquid Distributor RFQs: What Information Must Be Available Before a Supplier Can Design the Outlet Layout?
Liquid distributors are among the tower internals most sensitive to incomplete RFQs.
A supplier cannot reliably design an outlet layout from:
tower diameter and liquid flow alone.
The distributor must operate across an actual hydraulic range and fit around real vessel constraints.
Tower Diameter
The supplier requires the internal diameter at the distributor elevation.
For retrofit work, field confirmation may be necessary.
Liquid Flow Range
Do not provide only the normal flow if the tower operates at different rates.
The supplier should ideally know:
minimum, normal, and maximum liquid flow.
These conditions influence:
orifice sizing, liquid head, and turndown behavior.
Liquid Properties
Useful information includes:
density, viscosity, surface behavior, suspended solids, and fouling tendency.
Not every value is always available.
But dirty or crystallizing service should never be hidden from the supplier.
Distributor Type
If the project has already selected:
trough, pipe, pan, ladder-type, or another distributor,
state it.
If selection remains open, tell the supplier that alternatives may be proposed.
Feed Arrangement
The supplier needs to know how liquid enters the distributor.
This may include:
feed nozzle size, location, elevation, and orientation.
Without this, the distributor layout cannot be finalized.
Internal Obstructions
Support beams, chimneys, downcomers, nozzles, or other internals can occupy distributor area.
The supplier should receive drawings showing these obstructions.
Drip-Point Requirement
If the process design has already defined a minimum point density or distribution criterion, state it.
Otherwise, the supplier should declare the proposed outlet density and layout.
Fouling Risk
Small orifices may provide fine distribution but can plug more easily.
Therefore, fouling information is not optional in dirty services.
Manway and Assembly
Large distributors usually require sectional fabrication.
The supplier should receive the clear manway size before final fabrication drawings are prepared.
Scope
The RFQ should clarify whether the distributor package includes:
feed pipe, support, brackets, fasteners, gaskets, and installation hardware.
Engineering Takeaway
A liquid distributor RFQ must communicate both process hydraulics and vessel geometry.
Without flow range, liquid properties, feed arrangement, obstruction information, and installation access, only a preliminary quotation can be reliable.