Peristaltic pump tubing is specified by a size number (13#, 14#, 16# …) that looks random until you know the system: the number defines the bore, the wall thickness is fixed per series, and the OD follows from bore plus two walls. This page is the complete reference — every standard size with its ID, wall, OD, matching pump head and the flow it delivers.
The Complete 13#–18# Size Chart
The standard YZ-series family uses a 1.6 mm wall. Flows below are for a YZ1515x-style head at 600 rpm:
| Size | ID (mm) | Wall (mm) | OD (mm) | Max flow @ 600 rpm (ml/min) |
|---|---|---|---|---|
| 13# | 0.8 | 1.6 | 4.0 | 42 |
| 14# | 1.6 | 1.6 | 4.8 | 162 |
| 19# | 2.4 | 1.6 | 5.6 | 306 |
| 16# | 3.1 | 1.6 | 6.3 | 492 |
| 25# | 4.8 | 1.6 | 8.0 | 1,020 |
| 17# | 6.4 | 1.6 | 9.6 | 1,740 |
| 18# | 7.9 | 1.6 | 11.1 | 2,280 |
Which Head Takes Which Size
The wall thickness is the compatibility key — each head family is machined for one wall:
| Head family | Wall | Tubing sizes |
|---|---|---|
| YZ1515x-style | 1.6 mm | 13# 14# 19# 16# 25# 17# 18# |
| YZ2515x-style | 2.4 mm | 15# 24# |
| YZ35-style | 3.3 mm | 73# 82# |
The Large-Bore Family (2.4 mm and 3.3 mm Wall)
| Size | ID × Wall (mm) | OD (mm) | Head | Max flow (ml/min) |
|---|---|---|---|---|
| 15# | 4.8 × 2.4 | 9.6 | YZ2515x | 1,020 |
| 24# | 6.4 × 2.4 | 11.2 | YZ2515x | 1,740 |
| 73# | 9.6 × 3.3 | 16.2 | YZ35 | 7,400 |
| 82# | 13 × 3.3 | 19.6 | YZ35 | 12,000 |
Size + Material = The Complete Spec
The size chart picks the geometry; the material picks the chemistry. Match your fluid to the material family (silicone for general and food duty, EPDM for acids and hypochlorite, PTFE-lined for solvents, Viton for oils) and then confirm the material is available in your size — most standard sizes come in all four families.
FAQ
Is a bigger size number always a bigger tube?
Within the 1.6 mm-wall family, yes — 18# has a larger bore than 13#. Across families the wall changes too, so compare ID (bore) and wall, not the size number alone.
Can I use a 16# tube on a head rated for 13#?
Only if the head is machined for the 1.6 mm wall and the track accepts the larger OD. YZ1515x-style heads accept 13#–18#; check the head's documented tube list before swapping.
What does the wall thickness affect?
Pressure rating, tube life and how hard the rollers must squeeze. Thin walls occlude easily (better low-flow accuracy); thick walls handle more pressure and volume. See the full tubing guide for the selection process.