elbow line meaning in English

手肘线
肘围线

The height of the base shall be sufficient so that the centerline of the suction elbow lines up with the centerline of the suction piping and shall include an allowance for grouting between the concrete base and the pump mounting pedestal in accordance with the pump manufacturer ' s recommendations
根据泵制造商的建议，泵基座应该有足够的高度，使得吸入弯头的中心线能够与吸入管道中心线连接起来，混凝土基座与泵安装基座之间有足够的空间用于灌浆。