Does the Hydraulic three-way valve "L" with internal thread BSP, type BK3L support continuous operation at -40Â°C to +100Â°C given POM and NBR seal limits?

Hydraulic three-way valve "L" with internal thread BSP, type BK3L does not fully support continuous operation across the entire -40Â°C to +100Â°C range given the stated seal materials. Although the POM ball seal is rated -40Â°C to +100Â°C, the NBR stem seal is rated only -20Â°C to +100Â°C. The NBR lower limit of -20Â°C means continuous service below that temperature risks hardening, loss of elasticity and sealing failure. Therefore BK3L can operate continuously from -20Â°C to +100Â°C; operation between -40Â°C and -20Â°C would be outside the NBR specification and is not recommended for continuous use unless the NBR seal is replaced with a low-temperature-compatible material (e.g., FKM/fluoroelastomer or special low-temp NBR) or additional design measures are implemented.

Can Hydraulic three-way valve "L" with internal thread BSP, type BK3L operate continuously at -40Â°C considering NBR stem seal limits?

No. Hydraulic three-way valve "L" with internal thread BSP, type BK3L cannot be expected to operate continuously at â40Â°C when its stem seal is NBR, because NBRâs specified lower limit is â20Â°C. Although the valve listing shows POM-rated to â40Â°C for the ball, the stem seal material governs stem sealing performance; at â40Â°C NBR hardens and loses elasticity, risking leakage or seal failure. For continuous operation at â40Â°C use a version with a low-temperature-compatible stem seal (e.g. FKM fluoroelastomer or low-temp nitrile specifically rated to â40Â°C) or confirm manufacturer-approved low-temperature sealing options.

Are there any recommended pre-use checks for the Hydraulic three-way valve "L" with internal thread BSP, type BK3L regarding POM and NBR seals?

Yes. Before installing or using the Hydraulic three-way valve "L" with internal thread BSP, type BK3L with POM (ball) and NBR (stem) seals, perform these pre-use checks: 1. Visual inspection - Check POM ball and NBR stem areas for cracks, deformations, scoring or surface contamination. - Ensure no burrs or metal shavings are present inside the valve body or on threads. 2. Seal condition and compatibility - Confirm POM and NBR seals are the correct materials and properly seated. - Verify seals show no hardening, swelling, cuts or chemical attack. NBR is not suitable for strong ketones, some esters, or certain oils with high aromatic contentâconfirm fluid compatibility. 3. Temperature and fluid limits - Ensure intended operating temperature range falls within: POM -40Â°C to +100Â°C; NBR -20Â°C to +100Â°C. Avoid use below NBRâs lower limit or above either materialâs upper limit. - Confirm hydraulic fluid viscosity and additives are compatible with POM and NBR. 4. Pressure and mechanical checks - Verify system maximum pressure does not exceed valve specifications for high-pressure hydraulic installations. - Check threads (BSP internal) for damage; ensure proper mating fittings and correct thread sealing method (PTFE tape or sealant compatible with NBR/POM and hydraulic fluid). 5. Functional test - Cycle the valve through its positions off-line at low pressure to confirm smooth operation of the POM ball and stem movement, no sticking, and correct port switching. - Perform a low-pressure leak test around seals and threaded connections; then gradually pressurize to operating pressure while monitoring for leaks or seal deformation. 6. Installation hygiene and torque - Clean mating surfaces and remove debris. - Fit seals and components dry unless manufacturer specifies lubricant; if lubricating, use a lubricant compatible with NBR and POM and the hydraulic fluid. - Tighten fittings to recommended torques to avoid over-compression of NBR seals or deformation of POM components. 7. Recordkeeping - Note seal material, batch/inspection results, and any pre-service tests for future reference. If any defect, incompatibility, or abnormal behavior is found, do not put the Hydraulic three-way valve "L" with internal thread BSP, type BK3L into service until parts are replaced or manufacturer guidance is obtained.

Hydraulic three-way valve “L” with internal thread BSP, type BK3L

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Additional information

Material	CS – steel (cast iron)

High-quality three-way ball valve “L” type BK3L with internal BSP thread, designed for high-pressure hydraulic installations. Material: steel (body, ball, stem). Seals: POM (ball), NBR (stem). Operating temperature: from -40°C to +100°C (POM); from -20°C to +100°C (NBR).

List of product variants

Article number	Product variant name	DN	BAR	Availability	Actions
HZ-BK3L-G-02	Three-way valve "L" DN4 with 1/8" BSP thread, POM/NBR	4	400	In stock	Enquiry
HZ-BK3L-G-04	Three-way valve "L" DN6 with 1/4" BSP thread, POM/NBR	6	400	In stock	Enquiry
HZ-BK3L-G-06	Three-way valve "L" DN10 with 3/8" BSP female thread, POM/NBR	10	400	In stock	Enquiry
HZ-BK3L-G-08	Three-way valve "L" DN13 with 1/2" BSP thread, POM/NBR	12	350	In stock	Enquiry
HZ-BK3L-G-12	Three-way valve "L" DN20 with 3/4" BSP thread, POM/NBR	20	350	In stock	Enquiry

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High-quality three-way ball valve “L” type BK3L with internal BSP thread, designed for high-pressure hydraulic installations. Material: steel (body, ball, stem). Seals: POM (ball), NBR (stem). Operating temperature: from -40°C to +100°C (POM); from -20°C to +100°C (NBR).