Two labels, two opposite faces, one pass, and they have to line up with each other. That last requirement is the entire machine.
Applying a label to the front of a container is a solved problem. Applying one to the front and one to the back so that they are at the same height, the same distance from the seam, and square to each other, on every unit, is a product handling problem that a labeling head cannot solve on its own. A front and back labeling machine is built around that handling.
Marapack Services specifies, supplies, installs, commissions and services front and back labeling machines from a base in the Pacific Northwest. We are the Pacific Northwest distributor for Altech labeling systems, importing direct from the factory in Bareggio, Italy, and the equipment is built for beverage, food, cannabis, personal care and general manufacturing containers.
Send us the container and both labels: book an equipment audit and we tell you whether you need two heads, two heads with orientation, or a wrap.
What is a front and back labeling machine?
A front and back labeling machine applies two separate pressure sensitive labels to opposite faces of a container in a single pass, using two opposing labeling heads on one base while the container is gripped between twin side belts. Holding the container stops it rotating, which keeps the two labels at the same height and in register.
The trade also calls it a front and back labeler, a two sided labeling machine or a double sided label applicator. It is different from a wrap machine, which rolls one continuous label around the body, and from a top and bottom machine, which labels the lid and the base of a flat pack.
What does front and back mean on your line?
Three different requirements share the name. Two labels at matching height with nothing to line up is the simplest. Two labels in register with each other needs the container held, not rolled. Two labels in register with a seam, handle or mark needs orientation upstream. Each step up is a different machine and price.
We ask which of the three you are in before quoting, because the gap between the first and the third is a different machine, not an option.
Two labels, position not critical relative to the container. A round bottle with no seam, no handle and no embossed mark. The labels have to be at the same height and square, but nothing has to line up with a feature of the container. This is the least expensive version and it is a two head machine with a good hold.
Two labels, in register with each other. The front and back labels must be a specified distance apart around the circumference, typically opposite. Now the container's rotation between the two stations matters, which means it has to be held rather than rolled, or its rotation has to be controlled.
Two labels, in register with a feature of the container. A mold seam, a handle, an embossed logo, a tamper band, a previously applied label. This needs orientation: something has to find the feature and turn the container to a known position before labeling. This is the most expensive of the three and it is worth being told about early rather than late.
What is in a front and back labeling machine?
A front and back labeling machine is a linear base carrying two opposing heads, two heads matched to label length and line speed, a twin side belt hold that grips the container square, and spacing and orienting devices upstream. The hold decides the result; the heads are the easier choice.
The base
The ALline range provides complete linear labeling machine bases, and the relevant one here is the base built to carry two opposing heads. One head each side, working on the same container at the same point, so the two labels are applied in a single pass rather than in two passes with a turn between them. The bases and conveyor options are on our ALline linear labeling machine page.
The alternative, one head and a turning station, exists and is sometimes right on a slow line with a large container. It is slower and it introduces a second place for the container to move.
Conveyor options on the base include slat conveyors in 83, 115, 152, 191 and 254 mm widths (about 3.3, 4.5, 6, 7.5 and 10 in), roller conveyors with intermittent motion for products that must stop to be labeled, plus two way connections and 90 degree curved sections for building a real layout.
The heads
Two heads, matched to your label length and line speed:
- ALstep S, labels to 100 mm (about 3.9 in) at up to 30 m/min (about 98 ft/min)
- ALstep M, labels to 200 mm (about 7.9 in) at up to 20 m/min (about 66 ft/min)
- ALritma S, labels to 100 mm at up to 50 m/min (about 164 ft/min), IP54, color touchscreen, 40 stored label formats, and in a 200 mm version which is our volume seller
- ALritma L, labels to 300 mm (about 11.8 in) at up to 40 m/min (about 131 ft/min)
- ALritma X S, up to 40 m/min with an integrated 250 mm backing web rewinder, which matters on a two head machine because you now have two backing webs to deal with
That last point is worth dwelling on. A front and back machine generates twice the waste liner of a single head machine, and on a line with no rewind that means twice the operator interruptions. Integrated rewind on both heads, or a separate rewinder, is a specification decision rather than an accessory. The volume heads are described on our Altech ALritma range page, and every head type is compared on the applicator heads hub.
The hold
This is the part that makes or breaks the machine.
- Twin side belt systems at 1000 mm and 1500 mm (about 39 and 59 in) with height adjustment. Two driven belts hold the container square between them while both faces are labeled. This is the standard arrangement, and the reason it works is that the container cannot rotate while it is held.
- Stabilizing belts over the top of tall or light containers.
- ALbelt single belt conveyors in 200, 300 and 400 mm belt widths (about 8, 12 and 16 in), and a two section ALbelt, with belt width chosen for the pack, so the container has a stable belt before and after the labeling station.
- A vacuum kit for light empty containers that will not stay put.
Spacing and orienting
- Pneumatic gate, rubber wheel, side belt and timing screw spacers, plus twin roller gapping
- Side belt aligners to square the container before the station
- Double chain systems for elliptical containers and twin grippers for oval containers
- Double timing screw orienting and gapping where the container must arrive at a known rotational position, which is what a registration requirement actually needs
- Infeed and outfeed rotary accumulation tables so the machine is fed evenly
Which containers suit a front and back labeler?
Round bottles without registration, square and rectangular bottles, and tubs and jars suit a front and back labeler well. Bottles with a seam or embossed mark need orientation, and oval or elliptical bottles need gripper or chain handling. Flat packs, pouches and cartons are usually better served by a top and bottom machine.
| Container | Notes |
|---|---|
| Round bottle, no registration | The straightforward case. Side belt hold, two heads, done |
| Round bottle with a seam or embossed mark | Needs orientation. Ask about it before quoting |
| Oval or elliptical bottle | Needs twin gripper or double chain handling. A side belt alone will let it turn |
| Square or rectangular bottle | Easiest to hold, and often the least expensive front and back machine in this table |
| Tub, jar and short wide containers | The hold has to grip a short body without tipping it |
| Flat pack, pouch or carton | Frequently better served by lid and base labeling on a top and bottom machine |
| Tapered container | The two faces are not parallel. This constrains the hold and sometimes the label design |
When is a wrap the better answer?
A wrap is the better answer when the front and back labels are really one continuous label with two design areas. A wrap machine has one web instead of two, one head instead of two, and no registration between labels. Front and back stays right when the labels differ in stock or size, or must leave a clear window.
Check the artwork before the machine. If the front and back "labels" were designed as one piece, a wrap is simpler, and there is no registration problem between two labels because there are not two labels. Where splitting them is not possible, usually because the two labels are different stocks, different sizes, or have to leave a clear window between them, front and back is the right format. Wrap mechanisms and container handling are on our cylinder wrap labeling page.
How much does a front and back labeling machine cost?
A front and back labeling machine costs what its base, two heads, hold, and any orienting or inspection add up to. Which of the three registration requirements you have moves the price more than anything else, because orientation adds hardware upstream. We quote after seeing the container and both labels, not from a list price.
The other driver is rewind. Two heads make twice the liner waste, and whether that is handled by integrated rewind, a separate rewinder or an operator is a line item worth deciding at quote time rather than after the first week of running.
For every other machine format, from a single head on your conveyor to a complete line, see our automatic labeling machine options.
Sensing, coding and inspection
Clear labels on clear containers will defeat a standard gap sensor, and on a two head machine you now have two sensors to lose. The label tracing sensor built for transparent product is the fix and it is cheaper specified than retrofitted.
Variable data. If either label carries a date, lot or batch code, either print it at the moment of application with a print and apply head, or mark it onto the container or the applied label with a coder.
Proving both labels went on. Altech's label presence check and camera options can be ordered with the machine, with a product ejector where a missing label must not leave it. On a two head machine this matters more than usual, because a container missing its back label looks perfect from the front.
Frequently asked questions
Can we add a second head to the labeler we already have? Sometimes. The constraints are whether the base can carry a second head at the right position, whether the conveyor holds the container square, and whether there is space. A single head machine with a plain belt usually cannot become a front and back machine without a hold, which is most of the cost.
How do you keep the two labels in register? By not letting the container rotate between them. A twin side belt hold applies both labels while the container is gripped. Where the labels must also register with a feature of the container, you need an orienting device upstream, which is a separate item.
Can it do front and back plus a neck label? Yes, with a third head and the corresponding handling. Whether that is one machine or a second station depends on the container and the space.
Our back labels are lower than our front labels. Usually the hold rather than the heads. If the container tips or rides differently on one side, the label height follows it. Check side belt pressure and height adjustment before touching either head.
How fast can a front and back machine run? Head speeds go to 50 m/min on the ranges we sell, but on a two label machine the limit is usually product handling, not the head. Give us the container, the label size and the target rate and we will tell you which is the constraint.
Can you service a front and back machine you did not sell us? Yes. Altech, Label-Aire 3100 applicators and 5100 systems, PackLeader, CTM and Tach-It are all in our service scope.
Send us the container and both labels
We need the actual container, empty and full, and both actual labels, to tell you whether you are buying a two head machine, a two head machine with orientation, or a wrap. The difference between those three is the difference between a good quote and a surprise. Call 253-709-5566 or request a front and back line assessment.