API Spec 14L pdf download Lock Mandrels and Landing Nipples 6.3.1.2Lock mandrel and landing nipple equipment shall be manufactured to drawings and specifications thatare substantially the same as those used to manufacture the lock mandrel and landing nipple that has passedthe validation test. 6.3.1.3 Design Controls 6.3.1.3.1The supplier/manufacturer shall establish verified internal yield pressure, collapse pressure andminimum tensile strength, temperature...