Type B flexible joint cast iron soil pipe and fitting series are manufactured in compliance with the Chinese National Standard GB/T 12772-2016 "Flexible Joint Cast Iron Pipes, Fittings and Accessories for Drainage". The straight pipe sections are of W-Type or W1-Type (hubless design), while the fittings feature full hubs and are connected using a flange gland, sealing gasket, and fastening bolts. This system offers excellent sealing, high impact resistance, superior seismic performance, quick installation, easy maintenance, and reliable operation. Compared to Type A fittings, Type B provides both cost savings and space efficiency.  

1. Cut the W-Type or W1-Type straight pipe to the required length. Ensure both cut ends are perpendicular to the pipe axis, with smooth, even surfaces and no burrs to avoid damaging the rubber sealing gasket. 

2. Mark insertion depth lines on both spigot ends of the straight pipe. These lines must be perpendicular to the pipe axis. When connected, maintain approximately a 5 mm gap between the spigot end and the bottom of the fitting socket (hub).  

3. Slide the flange gland and then the rubber sealing gasket onto each spigot end of the straight pipe. Align the upper edge of the gasket with the marked insertion depth line on the spigot.  

4. When installing the straight pipe, insert its spigot ends into the sockets of the fittings. When installing a fitting, slide its socket onto the spigot end of the straight pipe. Ensure the rubber gasket is uniformly seated inside the socket in both cases.  

5. Insert bolts in the direction from the fitting toward the straight pipe. Tighten the bolts in a cross pattern, gradually and evenly, to apply uniform compression on the rubber sealing gasket.