Specifications

Adjustable Thermometer Holder · Specifications

Standard sizes are listed below. All products comply with GB/T, ASTM, and ISO standard taper systems. Full range 10/19 ~ 60/45 available. Custom cap materials, hose barb options, and offset angles are available.

Request custom specs

1. Standard Adjustable Thermometer Holder (Nylon Cap)

GB/T	ASTM	ISO	Fits Thermometer O.D. (mm)	Tube Length (mm)	Cap Material	Material
Please contact us to confirm the available specifications.

2. Adjustable Thermometer Holder (PTFE Cap)

GB/T	ASTM	ISO	Fits Thermometer O.D. (mm)	Cap Material	Material
Please contact us to confirm the available specifications.

3. Adjustable Thermometer Holder with Hose Barb

GB/T	ASTM	ISO	Hose Barb O.D. (mm)	Function	Cap Material	Material
Please contact us to confirm the available specifications.

* Joint numbers (14#, 19#) indicate the largest diameter (mm) of the taper. All are 1:10 taper.
* GB/ASTM/ISO designations are different standard identifiers — physical dimensions are identical and fully interchangeable.
* Full range 10/19 ~ 60/45 available upon request.
* Offset (angled) configurations available for multi‑neck flask applications.
* Standard O-ring material is rubber; Viton® upgrade available for enhanced chemical resistance.
* Contact our sales team for MOQ and lead time on custom orders.

✦ Customization Services — We offer custom joint sizes, cap materials, hose barb options, and offset angles. Share your specific requirements and our technical team will provide a tailored solution.

Product Description

The adjustable thermometer holder is a versatile component for mounting standard laboratory thermometers in standard taper glassware systems. Its key advantage over standard thermometer adapters is the ability to freely adjust the insertion depth of the thermometer bulb by loosening and tightening the nylon or PTFE cap. This allows the same apparatus to accommodate different liquid levels or measurement points, significantly improving experimental flexibility and temperature measurement accuracy.

The lower end features a precision-ground standard taper joint for secure connection to distillation heads, fractionating heads, and three-neck flasks. The upper end features a hollow nylon or PTFE cap with an O-ring that forms a reliable vacuum seal when tightened. Select models feature an 8mm hose barb on the side for inert gas introduction or vacuum connection, making them ideal for Schlenk line operations.

Key Features

Borosilicate Glass 3.3: Meets ISO 3585, low thermal expansion, thermal shock resistance up to 280°C, excellent chemical durability
Multi‑Standard Compliance: Precision‑ground 1:10 taper meets GB/T, ASTM E, and ISO 3585 standard taper specifications for full interchangeability
Adjustable Design: Loosen the cap to reposition the thermometer, tighten to seal — precise bulb positioning for any experiment
Dual Cap Materials: Nylon cap (cost-effective, general purpose) or PTFE cap (chemically resistant, ideal for aggressive environments)
Hose Barb Option: 8mm barb on select models for inert gas introduction or vacuum connection
Offset Option: Top angled approximately 10° for convenient use in multi-neck flasks

Quality Assurance

Each adjustable thermometer holder is inspected for taper accuracy, seal integrity, and surface finish to ensure reliable connection with all standard joint components. Custom bulk orders are welcome.

Tip: The adjustable thermometer holder fits standard laboratory thermometers with an outer diameter of 5.0~7.5mm. To adjust position, loosen the cap, reposition the thermometer, then retighten. Avoid over-tightening to prevent thermometer breakage. For hose barb models, ensure proper gas flow direction.

Applications

Typical Uses

Distillation

Adjust thermometer bulb position to measure vapor temperature at different heights

Reflux

Monitor reaction temperature with flexible positioning

Multi-Neck Flasks

Offset model provides convenient access in multi-port vessels

Schlenk Line Operations

Hose barb model enables simultaneous inert gas/vacuum connection

Precision Temperature Control

Fine-tune thermometer position for accurate measurements

Compatible Equipment

Standard joint distillation heads, fractionating heads, Claisen heads

Three-neck and four-neck flasks

Standard joint condensers, reactors

Schlenk tubes, Schlenk lines

Tip: The adjustable thermometer holder's key advantage is flexible thermometer positioning. Always use matching standard joint sizes for optimal sealing. For hose barb models, ensure proper gas flow direction and flow rate control.

Operation & Maintenance

User Guide

Before Use

Inspect for cracks, chips, or scratches on any joint
Check that the O-ring is intact and not deformed
Confirm thermometer O.D. is 5.0~7.5mm
Clean all joint surfaces with a soft cloth to remove particulates

Thermometer Installation & Adjustment

Insert the thermometer through the cap and O-ring into the holder
Adjust to the desired insertion depth (thermometer bulb position)
Tighten the cap to create a seal around the thermometer
To reposition, loosen the cap, adjust, then retighten
Avoid over-tightening to prevent thermometer breakage

Connection

Align the lower joint with the receiving apparatus and gently twist to seat
Use a clamp on the holder body for support
Hose barb model: connect inert gas or vacuum lines to the barb
For vacuum applications, ensure all joints are well-seated

Cleaning & Storage

Clean immediately after use to prevent residue buildup
Use soft brushes and appropriate detergents for the inner tube and joint
Replace O-rings if they show signs of aging (Viton® upgrade available)
Air dry and store with protective paper between ground joints
Protect joints from impacts