Conventional fracturing fluids formulated with hydroxypropyl guar gum (HPGG) and organoboron crosslinking agent have those problems such as high consumption of guar gum, excessive residue and high operation cost etc. Using a new crosslinking extender, the crosslinking environment can be changed, and the B(OH)4- ions necessary for crosslinking reaction are continuously provided by the organoboron in the gel fluid system, ensuring HPGG to do its utmost to gel at the lowest concentration. In this way the consumption of HPGG can be reduced, and formation damage by fracturing fluid residue can be minimized. With this theory, a series of low guar gum fracturing fluids used between 45 ℃ and 120 ℃ have been developed. Compared with conventional fracturing fluids, the consumption of HPGG in these low guar gum fracturing fluids was reduced by 20％ - 35％, and amount of residue reduced by 25％ - 30％. The temperature resistance, shearing resistance and sand carrying capacity of the low guar gum fracturing fluids are not compromised, and can satisfy the needs of field operations. The new fracturing fluids not only reduce formation damage, they also help reduce time required for fluid mixing and operation cost.%针对常规的羟丙基瓜胶和有机硼交联剂压裂液体系瓜胶使用量大、残渣多、成本高等问题,通过研究新型交联增效剂,改变交联环境,使有机硼交联剂在胶体体系内可以不断提供交联所需的B(OH)4-,保证常规羟丙基瓜胶在极限的低浓度下发挥出最高的成胶性能,从而达到降低瓜胶压裂液稠化剂用量、减少压裂液残渣对地层的伤害目的,形成了一系列在45～120℃下,能有效降低瓜胶用量的低浓度压裂液体系.与常规体系相比,羟丙基瓜胶的使用量下降20％～35％,体系的残渣量减少25％～30％,但体系的耐温性能、耐剪切性能,携砂能力不变,可充分保障施工要求,降低了压裂液体系对地层的伤害,也缩短了配液时间和施工成本.
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