The illustrated tank is a rotationally moulded polyethylene make-up tank standing in a stainless drip tray beside a washer, with a geared mixer on top, a sight tube on the side and a pump at its foot. Wall rating for specific gravity, containment and outlet fittings are fixed when the tank is ordered. The mixer is different: it adds weight, torque and a bending moment at the top of a plastic vessel that expands and contracts, and the tank maker and the mixer maker each say how that load has to be carried.
Covers polyethylene chemical tanks fitted with mixers, as used for make-up and feed solutions beside pretreatment washers: why mixing is needed, mixer mount types for poly tanks, the loads a mount must carry, support stiffness, access to the tank top, and alternatives to mechanical mixers. Wall thickness against specific gravity and bund capacity are on Reagent Storage Tank (823); day-tank sizing, calibration cylinders and 110% containment on Chemical Feed Tank and Pump (948); bottom outlet drain valves on Drain Valve (2817); the washer itself on the pretreatment system page.
CNFX editorial research · Sources checked October 13, 2026 · 5 sources
Three ways to mount a mixer on a polyethylene tank
Poly Processing, a polyethylene tank maker, explains why its tanks get mixers and offers mounts according to tank and mixer size.
The reason to mix at all, in Poly Processing's description: some chemicals separate, stratify or settle over time, and stagnant zones can create local concentrations above the compatibility rating of the tank material and fittings, so mixing protects the tank as well as the dosing. In the illustrated set-up the drawn solution goes straight to the washer, so a stratified tank would dose unevenly (editorial reading).
Poly Processing can drill the mixer shaft holes at the factory when it has the hole sizes and locations, and asks for the mixer to be supported by a bracketing system compatible with the particular tank.
Mount (Poly Processing)
Used for
Small freestanding mixer support
Small open-top tanks with small, lightweight mixers
Vertical-tank-supported mixer bridge
Small to medium vertical tanks
Large freestanding mixer bridge
Vertical and open-top tanks with very large mixers
Mount names and ranges are Poly Processing's for its own tanks; other tank makers set their own limits.
02
What the support has to carry: downward, bending and torque loads, and a deflection limit
Poly Processing lists what has to be known before the bracket is designed; Chemineer's manual for its 60DTD small mixer states how stiff the support must be.
The deflection limit scales with shaft length: 1/64 in per foot is about 1.3 mm per metre, so a 1.5 m extension shaft allows about 2 mm of movement at its end from support deflection (Editorial calculation).
Poly Processing lists the cost of an improperly mounted and bracketed mixer as improper mixing, wasted material and possible damage to the mixer or the tank. On a polyethylene tank the support also has to allow for the vessel's own movement: Poly Processing states that polyethylene expands and contracts with temperature and pressure, which is why it will not have platforms bolted directly to the tank.
Item
What the source states
Chemical
Properties and special handling of what is mixed; polymer blending needs special care (Poly Processing)
Tank
Cylindrical tank with a centre mount needing a baffle; mixer set at an angle and the X and Y intersects of that angle (Poly Processing)
Mixer loads
Downward load, bending load and torque load, and their angles, determine the bracketing (Poly Processing); required support design loads are on the mixer assembly drawing (Chemineer)
Stiffness
Support rigid enough that the extension shaft does not move more than 1/64 in (0.4 mm) per foot of length from deflection of the mounting (Chemineer)
Open-tank support
Two steel beams with lateral bracing, 45° diagonal bracing identical to the span beams, ends boxed in, beam size by tank diameter (Chemineer)
Installation
Never mount the mixer with shaft and propeller fitted; never use the extension shaft as a lifting point (Chemineer)
Chemineer's values are for its 60DTD model on an open tank; use the drawing and manual for the actual mixer.
03
Getting to the top, and mixing without a mechanical mixer
Mixers, level sensors and gauges on the dome need service, and a polyethylene tank top is not a working surface.
For a small make-up tank like the one illustrated, the practical consequences are a mixer light enough for a tank-supported bridge or its own stand, service reachable from a ladder or platform rather than from the dome, and a shaft material checked against the solution.
Point
Poly Processing's guidance
Walking on the tank
Polyethylene tanks cannot support handrails and should not be walked on; the dome can be slippery and the plastic can become brittle and crack under a person's weight
Access
Ladders from 6 to 20 ft meeting OSHA requirements, with cages or fall protection, optional 2 × 2 ft platform; a second ladder for sensors or mixers where needed
Platforms with handrails
Supported from the ground and connected to the tank with flexible brackets or slotted braces, designed by an engineer
Mechanical mixer drawbacks
Large brackets, metal shafts exposed to oxidizing chemicals, cost of mixer and bracket
Large-bubble mixing
Timed pulses of compressed air or gas released under accumulator plates on the tank floor lift bottom liquid to the surface
The closing paragraph is an editorial reading of Poly Processing's points for a small tank.
04
What to give a tank and mixer supplier
Paste it into your enquiry below or into an email to a maker, then replace every bracket.
Give the chemical and its concentration, specific gravity and temperature, the tank size, whether the solution separates or settles, the mixer type, power, shaft length and mounting angle, and the downward, bending and torque loads from the mixer drawing. Ask the tank maker for the mount type, bridge design and nozzle or hole positions, and the mixer maker for the support stiffness required and the wetted materials.
2 companies list this product among what they make. Company figures are quoted from each
company's own website; every card states where the relationship came from.
Jiangsu Prettech Machinery & Technology Co.,Ltd
TBC
Jiangsu Pretank Process lists chemical tanks, chemical mixing tanks and chemical storage tanks among its stainless steel vessels, with a paint-factory chemical tank project. Polyethylene versions and mixer mounts TBC; location TBC.
Product scope checked 2026-10-13
Own product menu: Chemical Tank, Chemical Mixing Tank · profile compiled by CNFX from public sources
Zibo Chunlei Chemical Machinery lists chemical tanks next to heat exchangers, chemical towers, heating furnaces and stainless reactors. Materials, mixer arrangements and ratings TBC; location TBC.
Explore company information and manufacturing capabilities, then discuss the scope of your project with a relevant supplier.
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Compiled and source-reviewed by the CNFX editorial team.
Each manufacturer above links to the page on that company's own website where the product is listed, with the date we checked it. How we source and review
· Page last updated 13 October 2026
Buyer questions
Can a mixer sit directly on a polyethylene tank top?
Poly Processing supports mixers on bracketing compatible with the tank: a small freestanding support, a tank-supported bridge for small to medium vertical tanks, or a freestanding bridge for very large mixers. [1]
What loads does a mixer bridge carry?
Poly Processing lists the downward load, bending load and torque load and their angles; Chemineer puts the design loads on the mixer assembly drawing. [3][5]
How stiff must a mixer support be?
Chemineer's 60DTD manual asks for a support rigid enough that the extension shaft moves no more than 1/64 in (0.4 mm) per foot of length from mounting deflection. [5]
Is there an alternative to a mechanical mixer?
Poly Processing describes large-bubble mixing: timed pulses of air or gas under accumulator plates on the tank floor. [2]
Can people stand on a polyethylene tank to service the mixer?
No. Poly Processing says polyethylene tanks should not be walked on and cannot support handrails; platforms must be supported from the ground. [4]
Sources and what still needs a direct check
Sources checked 2026-10-13. Four articles from a polyethylene tank maker on mixing and access, and a mixer maker's installation manual.
