CN102720898A - Preparation process of polyethylene sheath polyurethane heat-preserving pipe used under coal mine well - Google Patents
Preparation process of polyethylene sheath polyurethane heat-preserving pipe used under coal mine well Download PDFInfo
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- CN102720898A CN102720898A CN2012102255735A CN201210225573A CN102720898A CN 102720898 A CN102720898 A CN 102720898A CN 2012102255735 A CN2012102255735 A CN 2012102255735A CN 201210225573 A CN201210225573 A CN 201210225573A CN 102720898 A CN102720898 A CN 102720898A
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Abstract
The invention discloses a preparation process of a polyethylene sheath polyurethane heat-preserving pipe used under a coal mine well. The preparation process comprises the following steps of: (1) performing rust removing and corrosion prevention on a steel pipe which is qualified; (2) sleeving the steel pipe in a double-resistance polyethylene sheath; (3) filling polyurethane hard foaming plastic into an annular space between the steel pipe and the double-resistance polyethylene sheath, so that the polyurethane hard foaming plastic fully fills the annular space to form polyurethane hard foaming plastic heat-preserving layers; and (4) checking the finished product of the manufactured heat-preserving steel pipe. The heat-preserving steel pipe prepared by the preparation process is obvious in corrosion-preventing and heat-preserving effects and safer to use, and has flame-resistant and anti-static effects. The preparation method is simple and easy to operate, and mass industrial production is easy to perform, so that the cost is saved. The polyurethane foaming heat-preserving material used in the implement process is low in heat-conducting factor and water absorption rate and good in impermeability and chemical stability, and has flame-resistant and anti-static functions.
Description
Technical field
The present invention relates to general tubing under a kind of coal mine, be specifically related to a kind of underground mine use pe sheath polyurethane heat-insulation steel pipe preparation process.
Background technique
At present mostly China's coal mining mine is underground deep-well below 500 meters, and at underground more than 500 meters every dark 100 meters, downhole temperature just improves 2-3 ℃, mine more under the deep-well temperature high more, bring deterioration with regard to working environment like this to extractive industry.In order to improve this working environment, just must in deep-well, carry out cold and hot displacement and improve working environment.Originally domestic have a small amount of deep-well colliery when exploitation, adopts the ice refrigerating method.Be exactly in aboveground first ice making, again ice cube be transported to the down-hole, change ambient temperature.This mode cost is big, and efficient is low, weak effect.The method that adopts now is to carry the cold fluid medium down to deep-well, recycles.But at present China does not still have special being used for to carry the pipeline of cold fluid medium down to deep-well, owing to be the pipeline that deep-well uses, and will guarantee the temperature of cold fluid medium, so proposed to comprise insulation, new requirement such as safe, fire-retardant and antistatic.Present existing pipeline preparation process is still immature.
Summary of the invention
The object of the present invention is to provide a kind of underground mine use pe sheath polyurethane heat-insulation steel pipe preparation process.
The object of the invention can be realized through following technological scheme:
A kind of underground mine use pe sheath polyurethane heat-insulation steel pipe preparation process, it is may further comprise the steps: derusting anti-corrosive is carried out with the steel pipe that is up to the standards in (1); (2) steel pipe is inserted in two anti-polyethylene sleeve pipes; (3) annular space between steel pipe and two anti-polyethylene sleeve pipe injects polyurethane rigid foam plastic, makes polyurethane rigid foam plastic fully fill up annular space and forms the polyurethane rigid foam plastic thermal insulation layer; (4) insulating steel tube that completes is carried out the check of finished product.
Said two anti-polyethylene sleeve pipe is fire-retardant, antistatic polyethylene pipe.
The compound method of said polyurethane rigid foam plastic is: (1) preparation is material in vain: by weight, white material comprises 5 ~ 10 parts of 100 parts of PPGs, 1 ~ 4 part of silicone oil, 0.7 ~ 1.5 part of triethanolamine, 5 ~ 10 parts of fire retardants, anti-static agent and 0.4 ~ 1.5 part of distilled water; In reactor, add above-mentioned PPG and fire retardant, be warming up to 100 ~ 110 ℃, be cooled to 45 ~ 55 ℃ behind vacuum dehydration 0.5 ~ 1.5h, add above-mentioned silicone oil, triethanolamine, anti-static agent and distilled water, process white material; (2) the white material of step (1) preparation and black material are mixed post-polymerization by the weight proportion of 1 ~ 1.5:1 ~ 1.5, process polyurethane rigid foam plastic.
Described black material (isocyanates) is methyl diphenylene diisocyanate (MDI).The polyurethane rigid foam plastic of said method preparation is the polyurethane rigid foam plastic with independent hole-closing structure.
Above-mentioned fire retardant is a polyurethane flame retardant, and above-mentioned anti-static agent is the polyurethane electrostatic resistance agent.
The hydroxyl value of described PPG is 450～550 mgKOH/g, and molecular weight is 300～400.
Checking of finished products to the insulating steel tube that completes is: fire-retardant, anti-static electricity property to said two anti-polyethylene sleeve pipes and polyurethane rigid foam plastic are checked, and meet MT181-1988, MT113-1995 standard-required respectively.
The composition and the structure of underground mine use pe sheath polyurethane heat-insulation steel pipe are all fairly simple; Insulating steel tube is that the polyurethane rigid foam plastic thermal insulation layer of filling between a kind of steel pipe by fed sheet of a media, two anti-polyethylene sleeve pipe and steel pipe and the two anti-polyethylene sleeve pipe is combined closely and formed, and is the outer pillar urethane foam prefabricated thermal insulation steel pipe of a kind of high density polyethylene (HDPE).Only need the steel pipe socket behind the derusting anti-corrosive in the polyethylene sleeve pipe; The middle polyurethane rigid foam plastic that injects makes it fully to fill up the annular space between steel pipe and the two anti-polyethylene sleeve pipe, thereby forms a firm integral body; Reach the effect of corrosion-resistant thermal insulation, insulating steel tube has just formed like this.
Insulating steel tube is a kind of steel pipe that can improve warming temperature, its steel pipe heat insulation effect is better, acidproof, alkaline-resisting, oil resistant, corrosion-resistant, in light weight, cost is low, the service year limit for length.
Beneficial effect of the present invention:
The steel pipe of the underground mine use pe sheath polyurethane heat-insulation steel pipe of method preparation of the present invention and two anti-polyethylene sleeve pipe and the polyurethane rigid foam plastic thermal insulation layer between the two form a firm integral body; And the corrosion-resistant thermal insulation effect of steel pipe is remarkable; And have fire-retardant and antistatic effect, use safer.This steel pipe can squeeze or be embedded in underground, but site operation, and operating process is fairly simple, generally in the laying of use and building, finishing and pipeline, can be good at guaranteeing the normal and unobstructed of pipeline.Preparation method of the present invention is simple, and easy operating carries out large-scale industrial production easily, thereby saves cost.The polyurethane rigid foam plastic that is adopted in the inventive method implementation process, its thermal conductivity is little, and water absorption rate is low, and is impervious, chemical stability is good, and has fire-retardant and anti-static function.
Description of drawings
Fig. 1 is the structural representation of underground mine use pe sheath polyurethane heat-insulation steel pipe.
The two anti-polyethylene sleeve pipes of 1-steel pipe 2-polyurethane rigid foam plastic thermal insulation layer 3-.
Embodiment
Embodiment's 1 preparation polyurethane rigid foam plastic
The white material of preparation (combined polyether): by weight; (molecular mass is in 300～400 scopes by PPG for white material; Hydroxyl value is 450～550 mgKOH/g, and Jiangsu Zhongshang Chemical Co., Ltd. produces, model N-635B) 100 parts, 2 parts of silicone oil, 1 part of triethanolamine, 7.5 parts of fire retardants, 7.5 parts of anti-static agent and 1 part of composition of distilled water; In reactor, add above-mentioned PPG and fire retardant, be warming up to 105 ℃.Be cooled to 50 ℃ behind the vacuum dehydration 1h, add above-mentioned silicone oil, triethanolamine, anti-static agent and distilled water, process white material;
Described fire retardant is polyurethane flame retardant (DMMP), and kind Fine Chemical Co., Ltd produces on the Jinan.Described anti-static agent is polyurethane electrostatic resistance agent (GL-S), and Beijing gold journal stirrup chemistry Science and Technology Ltd. produces.
(limited company is learned in U.S. think of Dehua, Jiangsu to be provided described silicone oil; Model: AK-8804) be the non-hydrolysis-type foam stabilizing compound of a kind of high activity silicon-carbon bond, transparent viscous liquid, pH (25 ℃) 6.5 ± 1.0; 25 ℃ of viscosity (mPa.s): 600 ± 300,25 ℃ of (g/cm of density
3): 1.060 ± 0.030.
Mix post-polymerization with expecting in vain and deceiving the weight ratio of expecting by 1:1.45, process the polyurethane rigid foam plastic with independent hole-closing structure, described black material (isocyanates) is methyl diphenylene diisocyanate (MDI).
The hard foamed poly urethane of present embodiment preparation does not have stain, does not have the delamination splitting of contraction phenomenon.Abscess is evenly fine and closely woven.During requested test, the abscess average-size of radially measuring is not more than 0.5mm, and the rate of closed hole of foam is not less than 88%, and the foam density of polyurethane rigid foam plastic thermal insulation layer arbitrary position is not less than 60kg/m
3After in normal pressure boiling water, soaking 90min, the water absorption rate of polyurethane rigid foam plastic should be greater than 10%.
Embodiment's 2 preparation underground mine use pe sheath polyurethane heat-insulation steel pipes
(1) steel pipe 1 is tested, select up-to-standard steel pipe, remove the rusty stain on steel pipe 1 surface, the situation that steel pipe 1 is not corroded; Described steel pipe is seamless steel pipe or welded steel pipe.Steel tube surface is removed iron rust, mill scale, grease, dust, moisture or other contaminants; The steel tube surface rusting grade should meet A among the GB/T8923-1988, B, C regulation, and derusting grade also should meet the respective specified among the GB/T8923-1988.
(2) poling moulding is inserted in the steel pipe behind the derusting anti-corrosive 1 in two anti-polyethylene sleeve pipes 3, and the dead in line of said steel pipe 1 and two anti-polyethylene sleeve pipes 3 perhaps is slightly offset but the axis of said steel pipe and the distance between the polyethylene jacket tube's axis are no more than 8mm; Steel pipe 1 two ends is reserved 150mm～250mm exposed area in order to welding; Table 1 is the required specification that meets of deviation distance between two anti-polyethylene sleeve pipes and the steel pipe axis.
The required specification that meets of deviation distance between table 1 polyethylene sleeve pipe and the steel pipe axis
Said two anti-polyethylene sleeve pipe (Shandong Wen Yuan moulds industry Co., Ltd and provides) is black; Its internal surface range estimation does not have and loses the groove of its performance; Do not allow defectives such as bubble, crackle, depression, impurity, uneven color; Two anti-polyethylene sleeve pipes two ends should be cut smooth, and with the axis normal of two anti-polyethylene sleeve pipes, angular error should be less than 2.5 °.Two anti-polyethylene sleeve pipes are by the high-density polyethylene plastics manufacturing, and density of pe should be 935kg/m
3～950kg/m
3
The nominal outside diameter of two anti-polyethylene sleeve pipes and minimum wall thickness (MINI W.) should meet table 2 regulation.
The nominal outside diameter and the minimum wall thickness (MINI W.) requirement of table 2 pair anti-polyethylene sleeve pipe
The limit deviation that two anti-polyethylene jacket externals diameter of pipe and wall thickness allow should meet the GB/T13018 regulation.
The long-term mechanical properties of two anti-polyethylene sleeve pipes should satisfy the requirement of table 3.
The long-term mechanical properties of table 3 pair anti-polyethylene sleeve pipe
| Tensile force, MPa | The shortest surrender time, h | Test temperature, ℃ |
| 4 | 1500 | 80 |
(3) annular space between steel pipe and two anti-polyethylene sleeve pipe injects the polyurethane rigid foam plastic of embodiment's 1 preparation, and polyurethane rigid foam plastic fully fills up annular space and forms polyurethane rigid foam plastic thermal insulation layer 2; Steel pipe 1, polyurethane rigid foam plastic thermal insulation layer 2 and two anti-polyethylene sleeve pipe 3 are combined closely, form a firm integral body.During requested test, on arbitrary polyurethane rigid foam plastic thermal insulation layer cross section the area summation of hole and bubble account for the percentage of whole section area should be greater than 5%; Any direction size of single hole is no more than 1/3 of same position insulation layer thickness.Polyurethane rigid foam plastic thermal insulation layer radial compression intensity or radially relative deformation be that 10% o'clock compressive stress is not less than 0.3MPa.Thermal conductivity λ under 50 ℃ of states of the polyurethane rigid foam plastic thermal insulation layer that wears out
50Be not more than 0.033W/ ﹙ mK ﹚.The polyurethane rigid foam plastic insulation layer thickness should guarantee that outer pillar normally uses in-50 ℃～+ 50 ℃ temperature ranges.
Before and after polyurethane rigid foam plastic injected, the external diameter Magnification in same cross section, two arbitrary position of anti-polyethylene sleeve pipe should be greater than 2%.
(4) check of finished product is carried out in Checking of finished products to the insulating steel tube that completes.
Checking of finished products to the insulating steel tube that completes is: fire-retardant, anti-static electricity property to said two anti-polyethylene sleeve pipes and polyurethane rigid foam plastic thermal insulation layer are checked, and meet MT181-1988, MT113-1995 standard-required respectively.Prepared insulating steel tube was 120 ℃ of following continuous operations at least 30 years.
Polyethylene jacket tube-surface resistance arithmetic mean value is not more than 1.0 * 10
9Ω, combustion performance should meet the regulation of MT558.1-2005 standard.
Claims (6)
1. underground mine use pe sheath polyurethane heat-insulation steel pipe preparation process is characterized in that may further comprise the steps:
(1) steel pipe that is up to the standards is carried out derusting anti-corrosive;
(2) steel pipe is inserted in two anti-polyethylene sleeve pipes;
(3) annular space between steel pipe and two anti-polyethylene sleeve pipe injects polyurethane rigid foam plastic, makes polyurethane rigid foam plastic fully fill up annular space and forms the polyurethane rigid foam plastic thermal insulation layer;
(4) insulating steel tube that completes is carried out the check of finished product.
2. underground mine use pe sheath polyurethane heat-insulation steel pipe preparation process according to claim 1 is characterized in that said two anti-polyethylene sleeve pipe is fire-retardant, antistatic polyethylene pipe.
3. underground mine use pe sheath polyurethane heat-insulation steel pipe preparation process according to claim 1; The compound method that it is characterized in that said polyurethane rigid foam plastic is: (1) preparation is material in vain: by weight, white material comprises 5 ~ 10 parts of 100 parts of PPGs, 1 ~ 4 part of silicone oil, 0.7 ~ 1.5 part of triethanolamine, 5 ~ 10 parts of fire retardants, anti-static agent and 0.4 ~ 1.5 part of distilled water; In reactor, add above-mentioned PPG and fire retardant, be warming up to 100 ~ 110 ℃, be cooled to 45 ~ 55 ℃ behind vacuum dehydration 0.5 ~ 1.5h, add above-mentioned silicone oil, triethanolamine, anti-static agent and distilled water, process white material; (2) the white material of step (1) preparation and black material are mixed post-polymerization by the weight proportion of 1 ~ 1.5:1 ~ 1.5, process polyurethane rigid foam plastic.
4. underground mine use pe sheath polyurethane heat-insulation steel pipe preparation process according to claim 3 is characterized in that described black material is a methyl diphenylene diisocyanate.
5. underground mine use pe sheath polyurethane heat-insulation steel pipe preparation process according to claim 3 is characterized in that described fire retardant is a polyurethane flame retardant, and described anti-static agent is the polyurethane electrostatic resistance agent.
6. underground mine use pe sheath polyurethane heat-insulation steel pipe preparation process according to claim 3, the hydroxyl value that it is characterized in that described PPG is 450～550 mgKOH/g, molecular weight is 300～400.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201210225573.5A CN102720898B (en) | 2012-07-02 | 2012-07-02 | Preparation process of polyethylene sheath polyurethane heat-preserving pipe used under coal mine well |
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| CN201210225573.5A CN102720898B (en) | 2012-07-02 | 2012-07-02 | Preparation process of polyethylene sheath polyurethane heat-preserving pipe used under coal mine well |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103557404A (en) * | 2013-11-06 | 2014-02-05 | 北京豪特耐管道设备有限公司 | Production method of heat insulation pipeline and heat insulation pipeline adopting method |
| CN103753824A (en) * | 2013-12-04 | 2014-04-30 | 北京豪特耐管道设备有限公司 | High-temperature heat insulation pipeline production technology |
| CN105465504A (en) * | 2015-12-23 | 2016-04-06 | 山东鼎超供热设备有限公司 | Field connection method of plastic steel hot water pipeline in low-temperature environment |
| CN106366276A (en) * | 2016-08-26 | 2017-02-01 | 江苏中圣管道工程技术有限公司 | High-density rigid polyurethane foam material prefabricated heat insulating pipeline and prefabricating method |
| CN111140705A (en) * | 2020-01-06 | 2020-05-12 | 浙江青山新材料科技有限公司 | Nickel-containing heat-insulation steel pipe and preparation process thereof |
| CN113513639A (en) * | 2021-07-22 | 2021-10-19 | 江苏德誉环保设备科技有限公司 | Method for manufacturing anti-freezing water supply pipeline for mist system |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103557404A (en) * | 2013-11-06 | 2014-02-05 | 北京豪特耐管道设备有限公司 | Production method of heat insulation pipeline and heat insulation pipeline adopting method |
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| CN105465504A (en) * | 2015-12-23 | 2016-04-06 | 山东鼎超供热设备有限公司 | Field connection method of plastic steel hot water pipeline in low-temperature environment |
| CN106366276A (en) * | 2016-08-26 | 2017-02-01 | 江苏中圣管道工程技术有限公司 | High-density rigid polyurethane foam material prefabricated heat insulating pipeline and prefabricating method |
| CN111140705A (en) * | 2020-01-06 | 2020-05-12 | 浙江青山新材料科技有限公司 | Nickel-containing heat-insulation steel pipe and preparation process thereof |
| CN113513639A (en) * | 2021-07-22 | 2021-10-19 | 江苏德誉环保设备科技有限公司 | Method for manufacturing anti-freezing water supply pipeline for mist system |
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