I-ASTM A815 Ukucaciswa okuhlanganisa amakilasi amabili ajwayelekile, i-WP no-CR, we-Ferry Ferritic, Ferritic \
Aututenitic, kanye nokugcwaliswa kwensimbi engenasisekelo yokwakhiwa komthungo kanye nokwenziwa. Ukufakwa kwe-WP ye-Class ahlukaniswe ngama-subclass amane: amakilasi WP-S, WP-W, WP-WX-WX, ne-WP-WU. Izinto zokufakelwa ziba nokukhokhiswa, imigoqo, amapuleti, noma imikhiqizo ye-tubular engenamthungo noma ye-welded.