CN204493998U

CN204493998U - The online cold insulation structure of a kind of LNG sample

Info

Publication number: CN204493998U
Application number: CN201520171278.5U
Authority: CN
Inventors: 王海伟; 黎晖; 林素辉; 徐雷红; 汪杨柱; 郑飞萍; 陈海超
Original assignee: CNOOC Fujian Gas Co Ltd
Current assignee: CNOOC Fujian Gas Co Ltd
Priority date: 2015-03-25
Filing date: 2015-03-25
Publication date: 2015-07-22
Anticipated expiration: 2025-03-25

Abstract

The utility model relates to the cold insulation structure in a kind of LNG sample on-line period system, and one comprises cold insulation of LNG jacket pipe, and described cold insulation of LNG jacket pipe is arranged on LNG sampling line front end; Described cold insulation of LNG jacket pipe one end is provided with the link be connected with the LNG on-line period cut-off valve on LNG main line; The other end connects gasification pipe.Owing to being provided with cold insulation of LNG jacket pipe before sampling line, adopting the LNG of flowing as dynamic cold and heat insulation, LNG can be avoided before gasification fractionation to occur, ensure that uninstall process can get representational sample.

Description

The online cold insulation structure of a kind of LNG sample

Technical field

The utility model relates to the online cold insulation structure of a kind of LNG sample, belongs to LNG on-line period system regions.

Background technique

Need in LNG trade to measure LNG component, the general gas chromatograph that adopts is analyzed, and LNG need be changed into gas at normal temperature, make it to meet chromatographic requirement.Being arranged on discharging pipeline for the system of LNG sampling gasification be LNG (LNG Liquefied natural gas) on-line period system is design according to the requirement about Subcoold temperature in LNG sampling standard ISO8943, traditional static cold insulation pattern cold insulation limited efficiency.

Model utility content

The technical problem to be solved in the utility model cold insulation structure be to provide in a kind of LNG sample on-line period system overcomes the static cold insulation pattern of the prior art defect undesirable to LNG print cold insulation effect.

The technological scheme that the utility model solves the problems of the technologies described above is as follows: the cold insulation structure in a kind of LNG sample on-line period system, and comprise cold insulation of LNG jacket pipe, described cold insulation of LNG jacket pipe is arranged on LNG sampling line front end; Described cold insulation of LNG jacket pipe one end is provided with the link be connected with the LNG on-line period cut-off valve on LNG main line; The other end connects gasification pipe.

The beneficial effects of the utility model are: owing to being provided with cold insulation of LNG jacket pipe before sampling line, adopt the LNG of flowing as dynamic cold and heat insulation, LNG can be avoided before gasification fractionation to occur, and ensure that uninstall process can get representational sample.

On the basis of technique scheme, the utility model can also do following improvement.

Cold insulation structure in the present invention's a kind of LNG sample on-line period system described above, further, described cold insulation of LNG jacket pipe comprises tube layer and shell, and described tube layer and shell are all communicated with described LNG main line, are the LNG of supercooled state in it.

Above-mentioned further beneficial effect is adopted to be: on sampling line, be provided with cold insulation of LNG jacket pipe, when sample strain declines suddenly or cold insulation efficiency reduces, to be there is fractionation phenomenon in the LNG of shell, its enthalpy of phase change will reduce shell temperature, the effective Subcoold temperature ensureing tube layer LNG sample.

Cold insulation structure in the present invention's a kind of LNG sample on-line period system described above, further, the inlet of described cold insulation of LNG jacket pipe is provided with temperature transmitter.

The beneficial effect of above-mentioned further scheme is adopted to be: can observe at any time and enter LNG temperature vaporizer before from LNG cut-off valve owing to being provided with temperature transmitter and whether there is flash distillation.

Accompanying drawing explanation

Fig. 1 is the cold insulation structure schematic diagram in a kind of LNG sample of the utility model on-line period system.

In accompanying drawing, the list of parts representated by each label is as follows:

1, link, 2, shell, 3, tube layer, 4, temperature transmitter.

Embodiment

Be described principle of the present utility model and feature below in conjunction with accompanying drawing, example, only for explaining the utility model, is not intended to limit scope of the present utility model.

As shown in Figure 1, the cold insulation structure in a kind of LNG (LNG Liquefied natural gas) sample on-line period of the utility model system, comprise cold insulation of LNG jacket pipe, described cold insulation of LNG jacket pipe is arranged on LNG sampling line front end; Described cold insulation of LNG jacket pipe one end is provided with the link be connected with the LNG on-line period cut-off valve on LNG main line; The other end connects gasification pipe.Described cold insulation of LNG jacket pipe comprises tube layer and shell, and described tube layer and shell are all communicated with described LNG main line, are the LNG of supercooled state in it.When sample strain declines suddenly or cold insulation efficiency reduces, will there is fractionation phenomenon in the LNG of shell, its enthalpy of phase change will reduce shell temperature, the effective Subcoold temperature ensureing tube layer LNG sample.The inlet of described cold insulation of LNG jacket pipe is provided with temperature transmitter, can observe at any time to enter the LNG temperature before vaporizer from LNG cut-off valve and whether there is flash distillation.

The working principle that the utility model is novel: extract the cold sample of representative mistake by cold insulation of LNG jacket pipe from LNG main line, cold insulation of LNG jacket pipe under normal conditions, the LNG of shell and tube layer is in supercooled state, and its flow all calculates the flow value provided according to Subcoold temperature.When sample strain declines suddenly or cold insulation efficiency reduces, will there is fractionation phenomenon in the LNG of shell, its enthalpy of phase change will reduce shell temperature, the effective Subcoold temperature ensureing tube layer LNG sample.

The foregoing is only preferred embodiment of the present utility model, not in order to limit the utility model, all within spirit of the present utility model and principle, any amendment done, equivalent replacement, improvement etc., all should be included within protection domain of the present utility model.

Claims

1. the cold insulation structure in LNG sample on-line period system, is characterized in that, comprise cold insulation of LNG jacket pipe, described cold insulation of LNG jacket pipe is arranged on LNG sampling line front end; Described cold insulation of LNG jacket pipe one end is provided with the link be connected with the LNG on-line period cut-off valve on LNG main line; The other end connects gasification pipe.

2. the cold insulation structure according to claim 1 in a kind of LNG sample on-line period system, it is characterized in that, described cold insulation of LNG jacket pipe comprises tube layer and shell, and described tube layer and shell are all communicated with described LNG main line, are the LNG of supercooled state in it.

3. the cold insulation structure in a kind of LNG sample on-line period system according to claim 1 or 2, it is characterized in that, the inlet of described cold insulation of LNG jacket pipe is provided with temperature transmitter.