API · ASME · DIN · EN standard industrial valves
Lower Packing Needle Valves
Lower packing needle valves place the stem packing below the stem threads, keeping lubricant on the threads and corrosive or erosive media away from them — positive shut-off for higher-flow instrumentation duty. The range covers working pressure up to 5000 psig, -40°C to 232°C service, 316 SS bodies in straight or angle patterns, 316 SS V-stem or PCTFE soft-seal tips, orifice sizes up to 0.562 in. and end connections up to 1 in. for higher flow than typical instrumentation needle valves. Selection turns on the flow gain versus the 5000 psig ceiling, and the tube/pipe end mix the panel layout needs. Multi-source references add the operating frame: live-loaded packing below the stem threads paired with non-rotating stems for cycle life and leak-tight shut-off, dedicated lower-packing 400-series placement alongside integral-bonnet and severe-service lines, tapered-pin gradual opening for fine flow control, significant flow impedance until the plunger is fully retracted, spindle-based regulation, metering duty with linear flow characteristics where handwheel turns correlate directly to flow, reference metering stems of 40 threads per inch, and generic O-ring/TFE versus TFE packing-cylinder styles.
Part of the Needle Valves family
Last updated: 2026-10
Family specifications
| pressure class | Up to 5000 psig |
|---|---|
| temperature range | -40°C to 232°C (-40° to 450°F) |
| size range | up to 0.562 in. |
| end connection size max | up to 1 in. |
| stem tip | 316 SS V-Stem, PCTFE soft-seal |
| body materials | 316 SS |
| patterns | Straight, Angle |
| end connections | Duolok tube fitting, Unilok tube fitting, Griplok tube fitting, MNPT pipe fitting, FNPT pipe fitting, tube socket weld |
| end connection sizes | 1/8 in. to 1 in. |
| packing below threads ref | All packed bonnets feature live-loaded packing below the stem threads and non-rotating stems for better cycle life, lower maintenance and leak-tight shut off even in severe service conditions. |
| series placement | Offered as a dedicated lower-packing series (400 Series) alongside integral-bonnet and severe-service needle valve lines |
| tapered pin principle | An instrument needle valve uses a tapered pin to gradually open a space for fine control of flow. |
| retract impedance | As the screw is turned and the plunger retracted, flow between the seat and the plunger is possible; however, until the plunger is completely retracted, the fluid flow is significantly impeded. |
| spindle control | The flow can be controlled and regulated with the use of a spindle. |
| metering fine control | Metering valves are used for extremely fine flow control. The thin disk or orifice allows for linear flow characteristics. |
| handwheel turns correlation | Therefore, the number of handwheel turns can be directly correlated to the amount of flow. |
| metering thread pitch ref | A typical metering valve has a stem with 40 threads per inch. |
| packing styles generic | Needle valves generally use one of two styles of stem packing: an O-ring with TFE backing rings or a TFE packing cylinder. |
| pump governor duty | Most constant pressure pump governors have needle valves to minimize the effects of fluctuations in pump discharge pressure. |
| combustion control duty | Needle valves are also used in some components of automatic combustion control systems where very precise flow regulation is necessary. |
| lower packing component ref | Reference integral-bonnet parts list carries lower packing as a numbered component (item 7) |
| packing gland component ref | Reference integral-bonnet parts list carries a packing gland in 316 SS (item 5) |
| packing springs component ref | Reference integral-bonnet parts list carries packing springs (item 4) |
| peer turns large bore | 3/4 in and 1 in executions open fully in as few as 3 turns. |
| peer quick open turns | A quick-open execution is fully open in as little as 1-3/4 turns. |
| peer gland preload lock | The packing gland uses a preload locking internal thread form that resists vibration, eliminating the need for a separate locking device. |
| peer stem lift seat life | Stem geometry lifts the stem off the seat more than 2X faster than conventional designs, reducing throttling and extending seat life. |
| peer high temp packing | Temperature capability extends through graphite packing to 800 °F and extended stuffing boxes to 1200 °F on the hot end and -423 °F on the cryogenic end. |
| peer nace option | Valves can be manufactured to meet NACE MR-01-75. |
| peer brass envelope | Brass executions (screwed-bonnet or integral-bonnet forms) are rated for pressures up to 3,000 PSI and temperatures to 350 °F. |
| peer ptfe gland rationale | PTFE gland packing is used for its chemical resistance, low coefficient of friction and wide temperature tolerance. |
| peer nitrogen test limit | Factory acceptance testing: nitrogen at 1000 psig (69 bar) with a maximum allowable leak rate of 0.1 SCCM. |
| peer shell test option | Hydrostatic shell test at 1.5 times the working pressure is available as an option. |
| peer barstock orifice body | High-pressure bar-stock executions use a 0.197 in (5.0 mm) orifice with 316 stainless steel or carbon steel bodies. |
| peer union bonnet envelope | Union-bonnet instrument line envelope: orifice 0.156-0.437 in (4-11 mm), flow coefficient 0.35-2.2, end connections 1/4-1 in (6-25 mm). |
Scope & source notes
| packing scope | Packing scope: the reference statement covers all packed SSP bonnets with live-loaded packing below the stem threads, while the tenant page dedicates the term to the 400-series higher-flow instrumentation family - the reference phrasing is broader than the tenant family split. |
|---|---|
| thread pitch | Thread pitch: reference metering stems use 40 threads per inch as the typical pitch, while the tenant page states no stem thread pitch for its higher-flow line. |
| packing style | Packing style: the generic reference split of O-ring with TFE backing rings versus TFE packing cylinder does not map to the tenant V-stem/PCTFE soft-seal stem-tip framing - packing-system vocabulary differs between reference and tenant pages. |
| component inventory | Component inventory: the referenced integral-bonnet parts list includes lower packing, a lower gland and packing springs as separate components, while the tenant lower-packing page does not itemize its packing-stack components. |
Ordering & documentation
Documents
Ask for the documentation set with the inquiry — typical items (material certificates, test reports to the listed inspection standard, dimensional drawings) are confirmed and supplied with the quotation.
Quotation
Send the medium, temperature, pressure, size and connection for a quotation-ready inquiry. Lead time, MOQ and price are confirmed at quotation, together with the documents to be supplied with the order.
Sample & supply
Supply terms, order quantities and lead time are agreed per order — state the destination country and required schedule with the inquiry.
Storage & shipping
Store valves with seats and seals protected from UV, ozone and deformation, and keep end-face protectors on until installation; storage limits and shipping arrangements for the selected materials are confirmed at quotation.
Frequently asked questions
What sizes and pressure ratings are available for lower packing needle valves?
The published size range is up to 0.562 in., and the published pressure ratings are Up to 5000 psig. Availability of a specific size and rating is confirmed at quotation.
What materials are lower packing needle valves available in?
The published specification lists body materials: 316 SS. Material availability for a specific size and rating is confirmed at quotation.
What working temperature range do lower packing needle valves cover?
The published working temperature range is -40°C to 232°C (-40° to 450°F). For a medium at the edge of the range, confirm the suitability of the selected seat and body materials at quotation.
What end connections do lower packing needle valves support?
The published specification lists Duolok tube fitting, Unilok tube fitting, Griplok tube fitting, MNPT pipe fitting, FNPT pipe fitting, tube socket weld as the available end connections. The connection for a specific size is confirmed at quotation.
What should a quotation inquiry for lower packing needle valves include?
The governing standard and class, nominal size, body and seat materials, the service medium with temperature, and the destination — anything missing is confirmed during quotation.
Request a quote for lower packing needle valves
Submit the requirement here — a quotation-ready inquiry states the governing standard and class, size, materials, medium, temperature and destination.
What happens to your details is described in our privacy notice.
Get a quotation for Lower Packing Needle Valves
Send the standard, pressure class and size for a quotation-ready inquiry — answered with documents and terms.