Selecting a threaded nozzle and screw cap for a metal can involves more than matching one diameter. Buyers also need to confirm the thread profile, closure height, sealing component, opening structure, and the product that will be packed.
Yuexin supplies threaded nozzles and caps for metal cans from 18mm to 70mm, including standard, low-profile, and high-profile thread configurations. This guide explains how to compare the available sizes and what information to send before requesting samples or a quotation.
What Is a Threaded Nozzle and Screw Cap System?
A threaded metal can closure normally combines a nozzle or threaded base fixed to the can opening with a removable screw cap. Depending on the package design, additional sealing components can include a metal inner lid, pressure-sensitive liner, aluminum foil liner, plastic inner cap, pull-off inner cap, or foam liner.
This type of closure is useful when the package needs a cap that can be unscrewed and reclosed. If the project instead uses a press-fit closure, compare the options in our guide to 32mm, 42mm and 60mm finger press cap sizes.
18mm to 70mm Threaded Nozzles & Caps: Quick Comparison
Yuexin’s current threaded closure range covers the following standard series:
| Series | Fitting Diameter | Outer Cap Diameter | Total Height | Thread Profile | Common Sealing Options |
|---|---|---|---|---|---|
| 18mm | 18 mm | 30 mm | 18.5 mm | Standard | Aluminum foil liner |
| 30mm | 30 mm | 41 mm | 8 mm | Standard | Aluminum foil liner, metal inner lid |
| 32mm | 32 mm | 41 mm | 13.4 mm | Standard | Pressure-sensitive liner, plastic inner cap, pull-off inner cap |
| 42mm Low Profile | 42 mm | 57.8 mm | 12 mm | Low thread | Pressure-sensitive liner, plastic inner cap |
| 42mm High Profile | 42 mm | 57.8 mm | 19.7 mm | High thread | Plastic inner cap, pull-off inner cap |
| 47mm | 47 mm | 61.6 mm | 11.5 mm | Standard | Plastic inner cap |
| 55mm | 55 mm | 68.6 mm | 19.8 mm | Standard | Pressure-sensitive liner, plastic inner cap |
| 70mm Low Profile | 70 mm | 87.5 mm | 13.8 mm | Low thread | Foam liner, plastic inner cap |
| 70mm High Profile | 70 mm | 87.5 mm | 20 mm | High thread | Foam liner, plastic inner cap |
Important: a nominal diameter is only the starting point. A 42mm or 70mm closure can have different thread profiles and total heights, so the complete opening geometry must be checked before approving a replacement closure.
How to Choose the Correct Screw Nozzle & Cap Size
1. Measure the Fitting Diameter
Start with the diameter of the can opening that mates with the threaded nozzle assembly. If you already use an existing closure, send the current part or a dimensional drawing instead of relying only on the nominal size.
2. Check the Outer Cap Diameter and Overall Height
The closure needs enough clearance on the can top. For example, the 42mm series uses a 57.8mm outer cap diameter, while the 70mm series uses an 87.5mm outer cap diameter. Total height also changes between low- and high-profile versions.
3. Confirm the Thread Profile
Thread profile is especially important for 42mm and 70mm closures. A closure can share the same fitting diameter but still be incompatible if the thread height or matching geometry is different.
4. Define the Required Sealing Component
Different projects use different sealing arrangements. Common options in Yuexin’s current range include pressure-sensitive liners, aluminum foil liners, metal inner lids, plastic inner caps, pull-off inner caps, and foam liners. The correct option depends on the can design, opening structure, contents, and required opening method.
5. Test the Complete Assembly Before Bulk Production
For a new package or supplier change, confirm the nozzle, cap, and inner sealing component as one assembly. A physical sample-fit test is preferable to approving a closure from a diameter description alone.
Low-Profile vs High-Profile Threaded Closures
Yuexin offers both low- and high-profile versions in the 42mm and 70mm series. They share the same fitting diameter and outer cap diameter within each size family, but the total closure height differs substantially.
| Size Family | Low Profile Height | High Profile Height | Why It Matters |
|---|---|---|---|
| 42mm | 12 mm | 19.7 mm | The same nominal diameter does not mean the same thread geometry or assembled height. |
| 70mm | 13.8 mm | 20 mm | Confirm the can opening and existing closure profile before selecting a replacement. |
If you are replacing an existing closure, include a side-view photo and height measurement. This helps identify whether the existing can uses the low- or high-profile version.
How Do Different Liner and Inner-Cap Options Affect Selection?
Pressure-Sensitive Liner
Pressure-sensitive liners are available on selected series such as 32mm, 42mm low profile, and 55mm. They are one possible sealing component when the package design is compatible with this type of liner.
Aluminum Foil Liner
Aluminum foil liner options are used on selected smaller-diameter series, including 18mm and 30mm in Yuexin’s current range. When requesting this option, confirm the complete sealing process and compatibility with your package design.
Metal Inner Lid
A metal inner lid is available in selected configurations such as the 30mm series and can provide an additional internal closure component within the assembly.
Plastic Inner Cap
Plastic inner caps are available across several medium and large series, including 32mm, 42mm, 47mm, 55mm, and 70mm configurations. They can be useful where the package requires a separate internal closure component under the outer screw cap.
Pull-Off Inner Cap
Pull-off inner caps are available on selected configurations such as 32mm and 42mm high profile. The pull tab allows the inner closure to be removed when the package is first opened.
Foam Liner
Foam liners are available in the 70mm low- and high-profile series. As with any liner choice, compatibility should be confirmed with the intended package and contents rather than selected by material name alone.
Which Sizes Are Commonly Considered for Different Packaging Projects?
The correct closure is determined by the can opening, not just the container volume or product type. As a practical sourcing starting point:
- 18mm and 30mm: compact openings and smaller specialty containers.
- 32mm: small to medium metal cans requiring a standard threaded closure.
- 42mm: medium-diameter openings where low- and high-profile thread versions must be distinguished.
- 47mm and 55mm: intermediate larger openings that require their own matching cap geometry.
- 70mm: larger can and pail openings, with both low- and high-profile closure versions available.
These are selection directions, not interchangeability rules. Always verify the actual opening dimensions and thread profile.
What Should You Send With a Threaded Closure RFQ?
To reduce back-and-forth and improve the chance of matching the correct closure on the first sample, include:
- Required nominal size, if known
- Can opening diameter
- Thread profile or side-view dimensions
- Existing closure photos or physical samples
- Required outer cap and inner sealing components
- Product to be packed
- Surface finish or printing requirement
- Estimated order quantity
- Destination country
If you are unsure whether the opening is a 42mm low-profile or high-profile version, or whether a 70mm closure matches your current can, send photos and measurements before ordering.
Common Sourcing Mistakes to Avoid
Ordering by Diameter Alone
A 42mm cap does not automatically fit every 42mm opening. Thread height, total closure height, and mating geometry must match.
Ignoring the Inner Sealing Component
The outer screw cap is only one part of the closure assembly. Confirm whether the package also needs a liner, inner lid, plastic inner cap, or pull-off component.
Using a Container Capacity as the Main Specification
Two cans with the same nominal capacity can use different closure openings. The opening drawing or sample is more useful than the can volume alone.
Skipping Sample Approval
For a new project, a sample-fit check helps identify thread or assembly differences before mass production.
Frequently Asked Questions
What threaded nozzle and cap sizes does Yuexin supply?
Yuexin’s current standard range includes 18mm, 30mm, 32mm, 42mm, 47mm, 55mm, and 70mm series. The 42mm and 70mm families include both low- and high-profile versions.
Are 42mm low-profile and 42mm high-profile caps interchangeable?
Do not assume they are interchangeable. They share a 42mm fitting diameter and 57.8mm outer cap diameter, but the total height and thread profile differ. Confirm the matching opening geometry first.
What is the difference between the 70mm low- and high-profile versions?
Both use a 70mm fitting diameter and 87.5mm outer cap diameter. The low-profile version has a total height of 13.8mm, while the high-profile version is 20mm.
Can Yuexin supply liners and inner caps together with the screw closure?
Yes, selected series can be supplied with compatible sealing components such as pressure-sensitive liners, aluminum foil liners, metal inner lids, plastic inner caps, pull-off inner caps, or foam liners according to the closure configuration.
What if I do not know the thread profile?
Send a side-view photo of the existing closure and can opening together with measured dimensions. A physical sample or technical drawing is the most reliable reference for compatibility checking.
Need Help Matching a Threaded Nozzle & Cap?
If you are developing a new metal can package or replacing an existing closure supplier, send Yuexin your can opening dimensions, current cap photos or sample, required sealing components, quantity, and destination country.
View the complete 18mm to 70mm threaded nozzle and screw cap range, or contact Yuexin Metal Tech for a compatibility check and quotation.
