Valid

GB/T 261-2021Determination of flash point - Pensky-Martens closed cup method (English PDF)

闪点的测定宾斯基-马丁闭口杯法

Preview PDF

This is a limited preview

Buy now to download the full PDF (32 pages)

Need quotation for your management?

Get a formal quotation for GB/T 261-2021 in 30 minutes.

Issued by

SAMR; SAC

Level / Type

National · Recommended

Issue date

October 11, 2021

Implementation date

May 1, 2022

Scope

GB/T 261-2021 is the English-translated version of 闪点的测定宾斯基-马丁闭口杯法.

GB/T 261-2021 is the Chinese standard "Determination of flash point - Pensky-Martens closed cup method".

Its scope clause reads: This Document specifies the method for determining the flash point of flammable liquids, liquids with suspended particles, liquids that tend to form films on the surface under test conditions, and other liquids using a Pensky-Martens closed cup flash point tester.

NOTE 1: Although this Document can be used for kerosene with a flash point above 40°C, the flash point of kerosene is generally determined in accordance with GB/T 21789.

The flash point of unused lubricating oils is usually determined in accordance with GB/T 3536. NOTE 2: This Document can be used for jet fuels with a flash point below 40°C, but the precision has not been verified.

Warning: Since some mixtures do not obtain the flash point defined in this Document, but obtain a significantly increased flash (not the effect of halo) and a change in the flash from blue to yellow-brown, continued heating can cause the vapor around the test cup to burn.

This Document is applicable to samples with a flash point range of 40°C ~ 370°C. This Document includes three test steps: Step-A, Step-B and Step-C. Step-A is applicable to distillate fuels (including diesel, biodiesel blends, heating oil and turbine fuel), unused lubricating oils, paints and varnishes and other homogeneous liquids not included in Step-B and Step-C. Step- B is applicable to residual fuel oil, diluted asphalt, used lubricating oil, liquids with suspended particles, liquids that tend to form films on the surface under the test conditions or liquids whose viscosity is not suitable for heating under the stirring speed and heating conditions specified in Step-A. Step-C is applicable to the determination of BD100 biodiesel samples.

This Document does not apply to water-based paints and water-based varnishes. NOTE 3: When monitoring the lubricating oil system, in order to compare the flash points of unused lubricating oil and used lubricating oil, Step-A can also be used to determine the flash point of used lubricating oil, but this precision is only applicable to Step-B.

Found what you need?

Document preview — GB/T 261-2021

National Standard of the People's Republic of China

ICS: 75.080
Classification: E 30

Issued by: SAMR; SAC

Foreword3
Introduction6
1 Scope7
2 Normative References8
3 Terms and Definitions8
4 Overview of Method8
5 Reagents and Materials9
6 Instrument9
7 Preparation of Instrument10
8 Sampling11
9 Sample Processing11
10 Test Steps12
11 Calculations15
12 Expression of Results16
13 Precision16
14 Test Report17
Document and ISO 2719:201619
Appendix B (Informative) Instrument Calibration20
Appendix C (Normative) Pensky-Martens Closed Cup Flash Point Tester24
Equipment30
Bibliography32

1 Scope

This Document specifies the method for determining the flash point of flammable liquids, liquids with suspended particles, liquids that tend to form films on the surface under test conditions, and other liquids using a Pensky-Martens closed cup flash point tester.

NOTE 1: Although this Document can be used for kerosene with a flash point above 40°C, the flash point of kerosene is generally determined in accordance with GB/T 21789. The flash point of unused lubricating oils is usually determined in accordance with GB/T 3536.

NOTE 2: This Document can be used for jet fuels with a flash point below 40°C, but the precision has not been verified.

This Document is applicable to samples with a flash point range of 40°C ~ 370°C. This

Document includes three test steps: Step-A, Step-B and Step-C. Step-A is applicable to distillate fuels (including diesel, biodiesel blends, heating oil and turbine fuel), unused lubricating oils, paints and varnishes and other homogeneous liquids not included in Step-B and Step-C. Step-

B is applicable to residual fuel oil, diluted asphalt, used lubricating oil, liquids with suspended particles, liquids that tend to form films on the surface under the test conditions or liquids whose viscosity is not suitable for heating under the stirring speed and heating conditions specified in

Step-A. Step-C is applicable to the determination of BD100 biodiesel samples. This Document does not apply to water-based paints and water-based varnishes.

NOTE 3: When monitoring the lubricating oil system, in order to compare the flash points of unused lubricating oil and used lubricating oil, Step-A can also be used to determine the flash point of used lubricating oil, but this precision is only applicable to Step-B.

C.3.3 Ignitor

The diameter of the tip opening of the ignition tube flame jet device is about 0.7mm~0.8mm (see Figure C.4). The tip is stainless steel, or other suitable metal material. The ignitor is equipped with a mechanical operator. When the slide plate is in the "open" position, the tip is lowered so that the center of the flame nozzle opening hole is located between the upper and lower surface planes of the test cup cover and passes through a point on the center radius of the maximum opening A (see Figure C.3).

The bead at the tip is made of suitable material, about 4mm, which is equivalent to the flame size, and is assembled in a prominent position on the test cup cover.

C.3.4 Automatic ignition device

For automatic ignition of the flame, the diameter of the ignitor tip opening is about

0.7mm~0.8mm.

C.3.5 Stirring device

It is mounted in the center of the test cup cover (as shown in Figure C.4), with two double- bladed metal paddles. The lower paddle surface is about 38mm away from the test cup cover;

the two blades are 8mm wide and inclined at 45°. The upper paddle surface is about 19 mm from the test cup cover; the two blades are 8 mm wide and inclined at 45°. The two sets of paddles are fixed on the rotating shaft of the stirrer. When viewed from the bottom of the stirrer, the two blades of one set of paddles are at 0° and 180°; and the two blades of the other set of paddles are at 90° and 270°.

The rotating shaft of the stirrer can be connected to the motor by a transmission flexible shaft or a suitable pulley block structure.

C.4 Heating chamber and bath jacket

The test cup shall be provided with heat by designing a suitable heating chamber; the effect of the heating chamber is equivalent to an air bath. The heating chamber shall consist of an air bath and a bath jacket that can hold the test cup.

The air bath has a cylindrical inner side and meets the requirements shown in Figure C.1. The air bath can be flame-heated, electrically heated metal casting or resistance element heated. The air bath shall ensure that it does not deform at the specified temperature of the test.

If the air bath is flame-heated or electrically heated metal casting, in actual use, the temperature of its bottom and side walls shall be consistent; and the thickness of the air bath shall be no less than 6 mm. If the air bath is flame heated, the casting shall be designed so that the combustion products of the flame cannot move up the walls of the test cup or into the test cup.

If the heater is resistive, it shall be constructed so that all parts of the surface are heated evenly. […]

......
This preview omits tables, figures, formulas and parts of the technical clauses. The complete document — 32 pages — is available in the English PDF.

Referenced standards

Cited by

How to Download GB/T 261-2021

1
Add to cart
Click "Download PDF" on this page and choose "Buy this standard". You can add more standards before checkout.
2
Checkout
Enter your email and billing details. Payment is processed securely by Stripe (cards or bank transfer). Prefer bank details? Request a quotation (min. order $300).
3
Instant delivery (0–9 sec)
Delivery is automatic: within seconds of payment you'll receive an email with a secure download link. The link stays valid for 72 hours.
4
Invoice included
A tax invoice is attached to the confirmation email. Need a custom invoice? Contact us.