Conveyor symbols for P&ID and HMI
A belt conveyor is drawn as two circles joined by two parallel lines: the pulleys and the belt. A screw conveyor is a long rectangle with a helix inside. A bucket elevator is a tall, narrow version of the belt with buckets on the strand. On a P&ID they are static outlines; on an HMI the same outlines change colour with the motor state and, for reversible conveyors, light an arrow for the active direction.
In short
- Belt: two pulleys + two strands, arrow for direction.
- Screw: trough rectangle + helix line, motor at one end.
- Elevator: vertical belt with bucket marks, discharge at the top.
- HMI: one image per state, plus FWD / REV arrows when the belt reverses.
- Standard: ISA-5.1 does not cover conveyors; the project legend sheet rules.
The common conveyor symbols
Conveyors move solids, so they appear on the P&IDs of cement, mining, recycling, food, grain and waste plants rather than on liquid process drawings. Each type is recognised by the shape of its body:
Other members of the family reuse these bodies with a detail: a chain conveyor or drag chain is a belt with short cross-marks on the strand, an apron feeder is a heavy belt with plates, a pneumatic conveying line is simply a pipe with a blower and a receiver, and a chute is an inclined open channel with no drive at all.
Reading a belt conveyor symbol
The two circles are the pulleys: the drive pulley at the head, the tail pulley at the loading end. The two lines are the carrying strand and the return strand. Real drawings often add the drive as a motor circle marked M at the head pulley, sometimes with a gearbox block between them. Loading and discharge are shown with a short chute or an arrow, and the direction arrow sits above the belt. When the conveyor is inclined the whole symbol is tilted; the geometry does not change.
Tags and instrumentation around a conveyor
Conveyors are not instruments, so ISA-5.1 gives them no letter code. Most plants tag them with a plant-specific prefix such as CV-101, BC-101 (belt conveyor) or SC-201 (screw conveyor). What ISA-5.1 does cover is the protection around them, which is where the bubbles go:
- Belt misalignment switches at both edges, tagged
ZS(position switch) orZSH. - Zero speed or underspeed switch on the tail pulley,
SSL(speed switch, low). It proves the belt is really moving when the motor runs. - Pull cord emergency stops along the length,
HShand switches, usually feeding the safety PLC. - Plugged chute detector at the discharge,
LSH(level switch, high). - Belt weigher for throughput,
WT/WIT.
On the HMI these switches appear as small discrete indicators next to the conveyor body, or fold into the alarm badge of the conveyor object itself.
From P&ID glyph to live HMI object
On the operator screen the conveyor is a multi-state object: one image per state, switched by a word in the PLC. The conveyor is a motor with a belt on it, so it follows the same list as the 9 motor states:
| State | Colour | Meaning on a conveyor |
|---|---|---|
| Stopped | Gray | Motor off, belt still. |
| Starting | Green, flashing | Start command given, waiting for the speed switch. |
| Running | Green | Running with speed feedback. |
| No feedback | Yellow | Motor commanded but no speed signal: slipping belt or broken coupling. |
| Manual | Blue | Taken out of the sequence, run from the local box. |
| Disabled | Dark gray | Locked out for maintenance. |
| Fault | Red | Overload trip, pull cord, misalignment. |
Keep the body monochrome and let the fill carry the state, in line with the calm palette. A moving belt animation is tempting but distracts operators; a solid green fill plus the direction arrow is enough.
Reversible conveyors
Compactors, shuttle conveyors and some transfer belts run in both directions. Draw both arrows on the body and make them separate elements of the object: FWD lights when the forward contactor is closed, REV when the reverse one is. Both stay gray when stopped. In the PLC this is two extra state values, for example 3 = running forward and 4 = running reverse, so the multi-state lamp needs two images for "running" instead of one. The Symbol Builder supports this directly: the body follows the equipment state while each arrow shows only in the state you assign it to.
Geometry varies by project legend
There is no single normative conveyor glyph. ISO 10628 gives a few basic shapes, and every engineering company and end user has its own legend sheet that adds detail: chutes, skirts, scrapers, take-up units. Read the legend of the drawing set you are working on first, and treat the shapes here as the common, recognisable conventions. When you draw in the builder, match the line weight and proportions of that legend, or open a community conveyor symbol and adapt it.
Browse by category
Jump into the community library for the families on this page, or draw the set yourself:
Get conveyor symbols as PNG / SVG
Browse the conveyor symbols published in the community library (CC BY 4.0) and download with a free account, 5 a month on Free, or draw a reversible belt with all its states in the builder. The builder is free to use, no account needed.
Open the builder → Browse community conveyor symbols →Frequently asked questions
What is the symbol for a belt conveyor?
Two circles (the head and tail pulleys) joined by two parallel lines (the carrying and return strands), with a small arrow above for the direction of travel. On an HMI the outline is filled by state: gray stopped, green running, red fault.
What is the symbol for a screw conveyor?
A long rectangle for the trough with a zigzag or helix line inside for the flight. The drive is a motor circle marked M at one end. Some legends draw it as a cylinder with a coiled line instead.
How do you show a reversible conveyor on an HMI?
Draw two arrows on the body and light only the active one: FWD running forward, REV running in reverse, both gray when stopped. That is two extra values in the state word, so the multi-state object carries two "running" images.
Does ISA-5.1 define conveyor symbols?
No. ISA-5.1 covers instrumentation. Conveyor bodies come from ISO 10628 and company legend sheets, so the outline varies between projects. The legend sheet of the drawing set is the authority.
Where can I download conveyor symbols?
Browse the community library (Conveyors) and download PNG or SVG with a free account, or draw one with reversible arrows and the running states in the Symbol Builder.
Keep reading
- Gate, diverter and damper symbols — what controls the flow at the end of a conveyor.
- Tank, silo and hopper symbols — where the material comes from and goes to.
- The 9 motor states every HMI should show — the state list a conveyor object uses.
- HMI symbols for mining and bulk solids — conveyors in context.
- Build your own symbols — free online editor.
- Ask the community — a conveyor type your legend draws differently.