Capping valve and blow valve studs, nozzle flange studs, strainer plate bolts, refiner plate segment bolts and door swing bolts, made in Houston to your drawings and specifications.
Two pieces of pulp mill equipment side by side. On the left, a kraft batch digester 10 feet in diameter (the straight shell is drawn shortened to 10 feet so it fits the screen), with a 24-inch capping valve on the top neck, a circulation strainer ring feeding a pump and a liquor heater, and a 12-inch blow valve under the cone. On the right, a 52-inch disc refiner with a hinged door. They come apart the way a shutdown crew does it: the capping valve is unbolted and swung aside, the nozzle piping clears, the liquor heater channels come off, the blow valve is lowered and its bonnet drawn, strainer plates are unbolted and passed up through the neck, and the digester lifts off its support lugs. Then the refiner: piping off, the door swing bolts swung clear and the door opened, the plate segments unbolted from rotor and stator, the casing halves parted, the bearing caps and coupling undone, the rotor drawn off the shaft and the base lifted off its anchor bolts. The bolting we make is in colour. Press Solid view for a steel model, or Cutaway to see the digester wall, strainer and blow valve, and the refiner casing, plates and rotor in section.
Twenty 1-1/4 in. × 6-3/4 in. studs on a 29-1/2 in. bolt circle bolt the capping valve to the 24-inch top neck flange (ASME B16.5 Class 150). Chips are loaded through this opening.
Circulation extraction and return and the heater's liquor connections (NPS 8, eight 3/4 in. × 4-1/4 in. studs each); relief, liquor fill and steam (NPS 6, eight 3/4 in. × 4 in. studs each); heater steam and condensate (NPS 4, eight 5/8 in. × 3-1/2 in. studs each). All ASME B16.5 Class 150.
Twenty studs at each end of the liquor heater clamp the channel to the tubesheet. Shown at 7/8 in.; size and count are typical.
Twelve 7/8 in. × 4-3/4 in. studs on a 17 in. bolt circle at each of two joints: the valve to the cone outlet, and the blow line elbow to the valve (ASME B16.5 Class 150, NPS 12).
Twelve studs hold the bonnet on the valve body. Shown at 5/8 in.; the valve drawing governs.
Six bolts hold each of twenty screen plates to the support bars of the circulation strainer ring. Shown at 1/2 in.; size and count are typical.
Two bolts through each of eight support lugs into the ring girder. Shown at 1-1/8 in.; the structural design sets the size and count.
Three bolts through each of twelve plate segments on the rotor and twelve on the stator, into the plate holders. Replaced or re-used at every plate change. Shown at 5/8 in.; typical.
Twelve eye bolts pinned to the casing swing into slots in the door rim; their nuts clamp the door shut. Shown at 1-1/4 in.; typical.
Twenty-four studs join the two halves of the casing. Shown at 3/4 in.; typical.
Four bolts clamp the cap of each of the two split bearing housings. Shown at 7/8 in.; typical.
Fix the bearing housings to their pedestal and the casing feet to the base. Shown at 7/8 in.; typical.
Eight bolts join the coupling flanges between the motor and the refiner shaft. Shown at 3/4 in.; typical.
Eight 3/4 in. × 4-1/4 in. studs on the NPS 8 feed flange at the door, and eight 3/4 in. × 4 in. studs on the NPS 6 discharge flange on the casing (ASME B16.5 Class 150).
Eight anchor bolts cast into the foundation and up through the base, each with a washer and heavy hex nut. Shown at 1-1/4 in.; the foundation design sets the size and count.
Digester flange studs, strainer bolts and refiner plate bolts in stainless and duplex, to your drawing. Send us your drawings and material spec.
Request a quote832-446-3442A generic batch digester and disc refiner, not any maker's or mill's design, with the digester's straight shell drawn shortened. The nozzle, capping valve and blow valve flanges, their studs and gaskets follow ASME B16.5 and B16.20 Class 150. Everything else is typical: the shapes are illustrative typical proportions (digester, cones, neck, both valves, strainer ring, lugs and ring girder, heater, pump, piping and platform, and the whole refiner), as are the nozzle sizes and positions and the sizes and counts of the heater channel, bonnet, strainer, lug, plate segment, swing, casing, bearing, hold-down, coupling and anchor bolting. Stainless and duplex bolting is typical in liquor service; your material specification governs. Your drawings govern. We manufacture to your drawings and specifications.
The nozzle, capping valve and blow valve flanges, studs and gaskets are drawn to ASME B16.5 and ASME B16.20, Class 150; bolting materials are named to ASTM A193, A194 and F1554.
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