Safco Italia Z4 Foam Mixer 400 l/min, Series Z

A light inline foam mixer for hand-line foam branches

The Safco Italia Z4 is a compact aluminium foam mixer from the Series Z range. It meters foam concentrate into a water stream so that a foam branchpipe downstream receives a correctly proportioned foam solution. The maker describes the Series Z as particularly light and compact, and describes it as indispensable for correct mixing of the foaming liquid.

The Z4 is the 400 l/min size of a three-size family (Z2, Z4 and Z8). Each mixer is supplied with a 2.5 m suction tube that ends in a rigid steel terminal, so the concentrate can be drawn from a container through a STORZ 25 threaded connection. Safco Italia is the manufacturer named on the product sheet; Seven Star LLC supplies the range as an independent supplier.

Technical specifications

The product page lists the load capacity as 200 or 400 l/min and the thread connection as 2 inch, with UNI or STORZ on request. Weight and pressure rating are not stated on the Series Z sheet, so they are not shown here; please ask for them when you request a quotation.

Choosing between Z2, Z4 and Z8

Select the mixer by the maximum water flow it will see. The three sizes cover 200, 400 and 800 l/min with the same 2 inch connection and the same percentage dial. A Z4 suits a branch or monitor group in the 400 l/min class, for example a pair of the low expansion nozzles in the Fire Fighting range. The Z2 covers one smaller branch, and the Z8 is intended for higher flows.

Because the dial offers 0.5, 1, 3 and 6 %, the Z4 can be matched to concentrates that are specified at different induction rates. Always set the percentage that the foam concentrate manufacturer specifies for the hazard.

General engineering note (not from the sheet): inline mixers of this kind rely on a pressure drop across the unit to draw concentrate, so the inlet pressure and downstream back pressure must be checked against the mixer maker data for the flow in use.

Using the mixer in the field

• Connect the mixer between the pump or hydrant outlet and the foam branch, matching the inlet and outlet couplings to your hose system (UNI, BSS or STORZ on request).
• Put the steel suction terminal in the foam concentrate container and set the dial to the required percentage.
• Open water flow, then the foam branch; flush the mixer with clean water after use so concentrate does not dry inside the valve.

The user steps above are general good practice for inline foam proportioners; follow the manufacturer instructions delivered with the unit.

Concentrate consumption at 400 l/min

The dial setting decides how fast the foam concentrate container empties, and the arithmetic is simple: concentrate flow equals water flow multiplied by the percentage. At the full 400 l/min of the Z4, the settings on the dial give the following draw rates.

These figures are calculated from the rated flow and the dial percentages, not taken from the sheet. They show why a fire team using a 3 % or 6 % concentrate on the Z4 normally plans for drums or a bulk supply rather than single cans, and why the suction terminal should be moved to a full container before the first one runs dry.

Specifying a Z4 for a fire station or plant fire team

When the mixer is part of a vehicle kit or a plant foam trolley, check the complete line together: the pump or hydrant pressure, the hose length and diameter between the pump and the mixer, the hose between the mixer and the branch, and the branch itself. General engineering note (not from the sheet): long hose runs after an inline mixer increase back pressure, and too much back pressure stops the mixer from drawing concentrate, so keep the downstream line as short as the operation allows and test the set-up with water and a measuring container before relying on it.

General engineering note (not from the sheet): in hot, dusty sites such as those common in Oman and the GCC, store the mixer and suction tube out of direct sun, cap the couplings to keep sand out of the metering valve, and check the suction tube for cracking before each exercise. A short flow test with water after storage confirms that the dial and check valve move freely.

For a complete quotation, list the number of mixers, the size (Z2, Z4 or Z8), the coupling standard at inlet and outlet, the length of suction tube if a non-standard length is wanted, and the branches the mixer will feed.

Building a complete foam set

A working foam line needs more than the mixer. Typical items ordered together are a low expansion branch such as the S4 or a medium expansion branch such as the M4 at the same flow, lengths of lined delivery hose with matching couplings, coupling adaptors where the station uses more than one standard, and the foam concentrate itself in cans or drums. Ordering these as one set makes it easier to check that every coupling, thread and flow rating matches before the equipment reaches site, and it lets the whole line be tested with water as soon as it arrives.

Documents and quotation

The manufacturer product sheet (English) is attached to this page. Please send your required flow, coupling standard and concentrate type with your inquiry, and the quotation will confirm the correct model, code and delivery details.