A resin-made pipe joint with enhanced sealing property between a joint body and sleeve. A sealing portion which seals between an inner circumferential surface of an inserting portion of a sleeve and an outer circumferential surface of an inner cylinder portion is formed by press-inserting an inserting portion into a groove portion of the joint body. When the inserting portion is press-inserted into the groove portion, a space is formed between a body cylinder portion located opposite to an opening portion of the groove portion in the axial direction, and the projection end of the inserting portion. After completing press insertion of the inserting portion into the groove portion, in a section including axis of the inner cylinder portion, a region in the outer circumferential surface of the inner cylinder portion facing the space forms an angle of 5 to 15 to the axis of the inner cylinder portion.

A double containment fitting for connection to a double containment tubing system with an outer, secondary containment tubing surrounding an inner, primary tubing. The fitting includes a fitting body defining a central passageway, the fitting body having a center portion disposed between opposed first and second body ports. The fitting body is configured to receive the tubing system into the first body port. The central passageway has a diameter in the first port selected to allow the secondary tubing into the first body port. A connection system mechanically secures the secondary tubing to the first body port.

A pipe joint includes: an inner ring having a bulge portion to be press-fitted into an end portion of the tube; a joint body having an inner circumference into which an end portion of the inner ring is to be press-fitted, and having an external thread portion on an outer circumference thereof; and a union nut having an internal thread portion to be tightened to the external thread portion, and configured to press the end portion of the tube when the internal thread portion is tightened to the external thread portion. The bulge portion has a tapered portion configured to generate a surface pressure between the tube and the tapered portion by pressing by the union nut. An outer circumferential surface of the tapered portion has a concave surface portion formed in a concave surface shape in an axial cross-sectional view.

A tubing junction assembly may include a body, and a collar coupled to the body. The body may include a head portion, a base portion, and an intermediate portion. At least a portion of an outer surface of the body at the intermediate portion may define a cross-sectional width that tapers from the head portion to the base portion. The collar may have an inner surface defining a passage. A tubing may be stretched over the outer surface of the body with a proximal end portion of the tubing stretched over at least a portion of the outer surface of the body at the intermediate portion. The inner surface of the collar may be sleeved over a portion of the outer surface of the tubing and coupled to the collar such that the proximal end portion of the tubing is sandwiched and compressed between the body and the collar.

The present disclosure discloses a sealing pipe joint made of resin including a joint body, an inner ring, and a nut. The inner ring includes a plug head, the joint body includes a slot portion, the plug head is inserted within the slot portion to form a sealing connection. The nut is connected to the join body to maintain the plug head and the slot portion in a plugged state, the nut presses against the inner ring. In a free state, a radius thickness of the plug head is linearly changed along the the axis of the inner ring, and in plugged state, the slot portion is elastically deformed and a radius changing rate of the slot portion is less than that of the plug head when the plug head is in the free state.

A sealing pipe joint made of resin includes a joint body, an inner ring, and a nut. The inner ring includes a plug head, the joint body includes a slot portion, the plug head is inserted within the slot portion to form a sealing connection. The nut is connected to the join body to maintain the plug head and the slot portion in a plugged state, the nut presses against the inner ring. In a free state, a radius thickness of the plug head is linearly changed along the axis of the inner ring, and in plugged state, the slot portion is elastically deformed and a radius changing rate of the slot portion is less than that of the plug head when the plug head is in the free state.

A fitting nut made of a resin material includes: a hollow, large-diameter tube portion having a female thread formed on its inner peripheral wall; and a small-diameter tube portion that is continuous to the large-diameter tube portion and having a hollow cylindrical shape with a smaller diameter than the large-diameter tube portion. The small-diameter tube portion includes, in the outer peripheral wall thereof, a plurality of engagement grooves that are depressed inwardly in the diameter direction of the small-diameter tube portion and extend along the longitudinal direction that is orthogonal to the diameter direction.

A grip ring includes a substantially frustoconical metal ring body defining a diameter that tapers from a first lateral end of the ring body to a second lateral end of the ring body opposite the first lateral end, the ring body further defining a first circumferential end, a second circumferential end opposite the first circumferential end, an inner surface defining a guide ring opening, and an outer surface opposite the inner surface; and a gap defined between the first circumferential end and the second circumferential end; wherein the ring body is configured to be compressed radially inward to reduce a width of the gap between the first circumferential end and the second circumferential end.