UN R110 Supplement 3 (04 series) · UNECE Regulation No. 110 (ECE R110) — Uniform provisions concerning the approval of: I. Specific components of motor vehicles using compressed natural gas (CNG) and/or liquefied natural gas (LNG) in their propulsion system II. Vehicles with regard to the installation of specific components of an approved type for the use of compressed natural gas (CNG) and/or liquefied natural gas (LNG) in their propulsion system.
UN R110 — Supplement 3 to the 04 series of amendments
Supplement 2 → 3
- What changed
- New paragraphs 4.21.1. and 4.21.2. define two types of excess flow valve: the “pressure-equalization type” and the “shut-off type”.
- Annex 4A now requires the shut-off type excess flow valve to have a device to reset actuation manually. At cut-off position, leakage from the shut-off type valve must not exceed 2.5x10-7 normal m3/minute during operation.
- New paragraph 18.5.3.2. applies if the excess flow valve installed in the container is of a shut-off type per paragraph 18.5.1.1. For such a valve, any cover preventing access to the device to reset it must be removable without tools or other equipment.
- Why
- The proposal states that UN Regulation No. 110 permitted only the pressure-equalization type excess flow valve. At the time of operation, the pressure-equalization type does not completely shut off the fuel gas.
- OICA proposed an additional type of excess flow valve which can shut off the fuel, as an alternative to the current pressure-equalization type.
Q1What changed8 changes
Two types of excess flow valve (paras. 4.21.1. and 4.21.2.)
Paragraph 4.21.1. defines a “pressure-equalization type excess flow valve”: an excess flow valve which automatically resets when the excess flow condition is no longer present. Paragraph 4.21.2. defines a “shut-off type excess flow valve”. This is an excess flow valve that stops flow when in the closed position, which has to be reset by manual operation. Before this supplement, the Regulation had no paragraphs 4.21.1. and 4.21.2.
Excess flow valve on the CNG container (paras. 18.5.3.1. and 18.5.3.2.)
Paragraph 18.5.3.1. requires the excess flow limiting device to be fitted in the CNG fuel container(s) on/in the neck and on each CNG accumulator valve. Before this supplement, the text said “in the CNG fuel container(s) and on each CNG accumulator on the automatic cylinder valve”. New paragraph 18.5.3.2. applies if the excess flow valve installed in the container is of a shut-off type per paragraph 18.5.1.1. In that case, any cover preventing access to the device to reset the excess flow valve must be removable without tools or other equipment. The text gives the manual valve as an example of this device.
Annex 4A, paragraph 5.4.: bypass for the pressure-equalization type, manual reset for the shut-off type
Annex 4A, paragraph 5.4. now says “The pressure-equalization type excess flow valve” instead of “The excess flow valve” in the bypass requirement. Paragraph 5.4. also says “allow for equalization pressures” instead of “allow for equalization of pressures”. A new sentence in paragraph 5.4. requires the shut-off type excess flow valve to have a device to reset actuation manually. For example, the actuation of such a shut-off type excess flow valve can be cancelled by operating the manual valve.
Annex 4A, paragraph 5.6.: leakage limit for the shut-off type at cut-off position
Annex 4A, paragraph 5.6. now says “the pressure-equalization type excess flow valve” instead of “the excess flow valve” in the by-pass flow limit at cut-off position. The limit of 0.05 normal m3/minute at a differential pressure of 10,000 kPa does not change. Under a new sentence in paragraph 5.6., leakage from a shut-off type valve at cut-off position must not exceed 2.5x10-7 normal m3/minute during operation.
Q2Why it changed
- Proposed by
- Expert from OICA
- Working party
- GRSG, 121st session (April 2021)
Reasons
The proposal states that UN Regulation No. 110 permitted only the pressure-equalization type excess flow valve. At the time of operation, this type does not completely shut off the fuel gas. This type limits the gas flow rate at the time of actuation.
Sources (3)
“In the UN Regulation No.110, only the excess flow valve (EFV) for the pressure-equalization type is permitted.”
“At the time of operation, the pressure-equalization type EFV does not completely shut off the fuel gas.”
“the pressure-equalization type EFV plays a role of limiting the gas flow rate at the time of actuation.”
The proposal aimed to add provisions for excess flow valves which can shut off fuel flow at the time of operation, to specific components. OICA proposed an additional type of excess flow valve which can shut off the fuel, as an alternative to the current pressure-equalization type.
Sources (2)
“with the aim of adding provisions for excess flow valves (EFV) which can shut off fuel flow at the time of operation, to specific components.”
“In this document, OICA proposes, as an alternative to the current pressure-equalization type EFV, an additional type of EFV which can shut off the fuel.”
The proposal explains that the actuation of a shut-off type excess flow valve can be cancelled by operating the manual valve.
Source
“The actuation of such shut-off type EFV can be cancelled by operating the manual valve.”
Document trail
- 2021-01ProposalECE/TRANS/WP.29/GRSG/2021/10Proposal by the expert from OICA
- —RevisedGRSG-121-22Amendments by OICA to document GRSG/2021/10
- —Working party adoptsECE/TRANS/WP.29/GRSG/100Session report, para. 70: GRSG adopted the proposal as amended by GRSG-121-22 and in session
- 2021-09Sent to WP.29ECE/TRANS/WP.29/2021/107Text that GRSG sent to WP.29 and AC.1
- 2021-11WP.29 adoptsECE/TRANS/WP.29/1161Adopted at the 185th session (session report, para. 121)
- 2022-06-22In forceC.N.230.2022.TREATIES-XI.B.16.110UN depositary notification
Q3Who is affected
Vehicle manufacturer
- In the case of paragraph 18.5.3.2., make any cover over the reset device removable without tools or other equipment.
- Fit the excess flow limiting device in the CNG fuel container(s) on/in the neck and on each CNG accumulator valve.
Component supplier
- Make sure a shut-off type excess flow valve has a device to reset actuation manually.
- Make sure a shut-off type excess flow valve at cut-off position leaks no more than 2.5x10-7 normal m3/minute during operation.
Technical service / Approval authority
- Be ready to check that shut-off type valves at cut-off position leak no more than 2.5x10-7 normal m3/minute during operation.
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ⓘ This report gives advice only. It is not legal or type-approval advice.