Butt-Weld Tie-Rod Tubular Sight Glass

An inline sanitary tie-rod tubular sight glass featuring butt-weld tube ends, a replaceable tempered glass viewing cylinder, and exterior stainless steel tie bolts. Offered in SS304 and SS316L across 1/2"–4" with a DIN weld-end dimensional drawing (DN25–DN100).

Body Material	SS304 / SS316L (304 / 316L)
End Connection	Butt-Weld Ends
Body Construction	Tie-Rod Tubular Housing with Replaceable Tempered Glass & Stainless Steel Bolts
Nominal Size Range	1/2"–4" (DN25–DN100)
Drawing Standard	DIN

Size

Request a quote View specifications

Butt-Weld Process Ends and Open Tie-Rod Glass Cage

This straight welded sight glass mounts inline via butt-weld spigots on both ends and secures a replaceable tempered glass cylinder between four exterior stainless steel tie bolts. The open tie-rod frame provides 360-degree visual inspection of fluid flow, color, and CIP rinse clarity.

Specification Range and DIN Weld-End Drawing Dimensions

The series specification table lists nominal sizes 1/2", 3/4", 1", 1.5", 2", 2.5", 3", and 4". The paired DIN sight glass weld end drawing details metric sizes 25, 32, 40, 50, 65, 80, and 100, with bore A from 25 to 100 mm, weld spigot OD B from 28 to 104 mm, flange diameter C from 79.0 to 159 mm, and overall length D from 136 to 152 mm.

Material Grades and Gasket Selection

CNC-lathed from SS304 or SS316L stainless steel, the sight glass is available with VMQ (silicone), EPDM, Viton, or PTFE gaskets (source-claimed tempered glass rating up to 10 bar) for food, dairy, beverage, meat processing, vacuum, pharmaceutical, and chemical applications.

Pre-Weld Disassembly and Ordering Notes

Disassemble the tie bolts and remove the tempered glass cylinder and elastomer seals before welding the end rings into the pipeline, reassembling once the weld zones cool. Specify any required heat numbers or MTR certificates when ordering.