US 11,673,297 B2
Molding method for producing a stator for a screw drilling tool using elastomer material
Dingyu Guo, Calgary (CA); Hongrui Zhang, Tianjin (CN); Minghui Zhu, Shanghai (CN); Yiran Liu, Xuzhou (CN); Zhuanrui Liu, Xuzhou (CN); Paul Kwong Shun Cheung, Calgary (CA); and Xiaobo Liu, Chengdu (CN)
Assigned to SHANGHAI PUJIA DRILLING TECHNOLOGY CO., LTD., Shanghai (CN)
Filed by SHANGHAI PUJIA DRILLING TECHNOLOGY CO., LTD., Shanghai (CN)
Filed on Apr. 9, 2020, as Appl. No. 16/843,908.
Application 16/843,908 is a continuation of application No. PCT/CN2019/082764, filed on Apr. 15, 2019.
Claims priority of application No. 201811211495.7 (CN), filed on Oct. 17, 2018.
Prior Publication US 2020/0230845 A1, Jul. 23, 2020
Int. Cl. F04C 2/107 (2006.01); B29C 33/38 (2006.01); B29C 39/10 (2006.01); B29C 39/00 (2006.01); B29C 39/26 (2006.01); B29C 39/36 (2006.01); B29B 13/00 (2006.01); B29C 33/58 (2006.01); B29C 35/02 (2006.01); B29K 9/00 (2006.01); B29K 105/24 (2006.01); B29C 33/64 (2006.01); B29C 37/00 (2006.01); C08G 18/12 (2006.01); C08G 18/32 (2006.01); C08G 18/38 (2006.01); C08G 18/48 (2006.01); C08G 18/76 (2006.01); C09J 175/08 (2006.01); C09J 175/12 (2006.01); C08G 18/69 (2006.01)
CPC B29C 39/10 (2013.01) [B29C 39/006 (2013.01); B29C 39/26 (2013.01); B29C 39/36 (2013.01); F04C 2/1075 (2013.01); B29B 2013/005 (2013.01); B29C 33/3842 (2013.01); B29C 33/58 (2013.01); B29C 33/64 (2013.01); B29C 35/02 (2013.01); B29C 37/006 (2013.01); B29K 2009/00 (2013.01); B29K 2105/24 (2013.01); C08G 18/12 (2013.01); C08G 18/3243 (2013.01); C08G 18/3872 (2013.01); C08G 18/4804 (2013.01); C08G 18/4833 (2013.01); C08G 18/4854 (2013.01); C08G 18/69 (2013.01); C08G 18/7621 (2013.01); C09J 175/08 (2013.01); C09J 175/12 (2013.01)] 9 Claims
 
1. A molding method for producing a stator for a screw drilling tool using an elastomer material, comprising steps of:
S1, roughening an inner surface of a stator tube of the stator, and then cleaning and drying the inner surface of the stator tube; uniformly mixing an adhesive and a diluent, coating the mixture obtained on the inner surface of the dried stator tube, and heating the inner surface of the stator tube for later use; wherein the adhesive comprises epoxy resin adhesive, and the diluent comprises at least one of butanediol and glycerin, and a mass ratio of the adhesive to the diluent is (0.72 to 0.91): (0.09 to 0.28);
S2, uniformly coating a mold release agent on a surface of a mandrel mold, and heating or natural drying the surface of the mandrel mold for later use;
S3, assembling the stator tube processed in step S1 and the mandrel mold processed in step S2 to obtain an assembled mold;
S4, performing a vacuum defoaming under negative pressure on a mixture obtained by uniformly mixing a prepolymer of the elastomer material with a defoaming agent; and
S5, uniformly mixing the prepolymer of the elastomer material defoamed in step S4 with a curing agent, and pouring the obtained mixture into the assembled mold obtained in step S3, sealing and curing the poured assembled mold by hierarchical heating; after the curing is completed, drawing the mandrel mold from the assembled mold, so that the stator is obtained.
 
6. A molding method for producing a stator for a screw drilling tool using an elastomer material, comprising steps of:
S1, roughening an inner surface of a stator tube of the stator, and then cleaning and drying the inner surface of the stator tube; uniformly mixing an adhesive and a diluent, coating the mixture obtained on the inner surface of the dried stator tube, and heating the inner surface of the stator tube for later use
S2, uniformly coating a mold release agent on a surface of a mandrel mold, and heating or natural drying the surface of the mandrel mold for later use;
S3, assembling the stator tube processed in step S1 and the mandrel mold processed in step S2 to obtain an assembled mold;
S4, performing a vacuum defoaming under negative pressure on a mixture obtained by uniformly mixing a prepolymer of the elastomer material with a defoaming agent; and
S5, uniformly mixing the prepolymer of the elastomer material defoamed in step S4 with a curing agent, and pouring the obtained mixture into the assembled mold obtained in step S3, sealing and curing the poured assembled mold by hierarchical heating; after the curing is completed, drawing the mandrel mold from the assembled mold, so that the stator is obtained wherein in step S4, the prepolymer of the elastomer material includes component A and component B, wherein, the component A comprises hydroxyl-terminated liquid rubber, polytetrahydrofuran diol and polyether polyol, and a mass ratio of hydroxyl-terminated liquid rubber, polytetrahydrofuran diol and polyether polyol is (0.2 to 1.0): (0.2 to 1.0): (0.2 to 1.0); and the component B comprises at least one of isocyanate, cyanate, and cyano compound.
 
9. A molding method for producing a stator for a screw drilling tool using an elastomer material comprising steps of:
S1, roughening an inner surface of a stator tube of the stator, and then cleaning and drying the inner surface of the stator tube; uniformly mixing an adhesive and a diluent, coating the mixture obtained on the inner surface of the dried stator tube, and heating the inner surface of the stator tube for later use;
S2, uniformly coating a mold release agent on a surface of a mandrel mold, and heating or natural drying the surface of the mandrel mold for later use;
S3, assembling the stator tube processed in step S1 and the mandrel mold processed in step S2 to obtain an assembled mold;
S4, performing a vacuum defoaming under negative pressure on a mixture obtained by uniformly mixing a prepolymer of the elastomer material with a defoaming agent; and
S5, uniformly mixing the prepolymer of the elastomer material defoamed in step S4 with a curing agent, and pouring the obtained mixture into the assembled mold obtained in step S3, sealing and curing the poured assembled mold by hierarchical heating; after the curing is completed, drawing the mandrel mold from the assembled mold, so that the stator is obtained; wherein the curing by hierarchical heating is performed by curing through heating step by step, including 2 to 6 steps of heating, wherein, a temperature for curing is 60° C.˜160° C. and a time for curing at each stage is 1.5˜5 h.